monitoring results would be representative of the most highly exposed
persons in the workplace. Additionally, analogous to the OSHA standard,
EPA expects that owners and operators would conduct initial exposure
monitoring representative of all tasks a potentially exposed person
would be expected to do. EPA understands that certain tasks may occur
less frequently or may reflect upset conditions (for example, due to
malfunction). EPA is soliciting comments regarding how owners and
operators could conduct initial exposure monitoring to ensure that it
is representative of all tasks likely to be conducted by potentially
exposed persons.
    EPA also recognizes that the values for the ECEL action level and
EPA STEL may mean that some owners or operators currently in compliance
with the OSHA standard would have to re-establish a monitoring
baseline. Aligning with the existing OSHA standard (29 CFR
1910.1052(d)(2)) to the extent possible, EPA is proposing that an owner
or operator may temporarily forgo initial exposure monitoring if:
    (i) An owner or operator could provide EPA with objective data
generated during the last 5 years demonstrating that methylene chloride
cannot be released in the workplace in airborne concentrations at or
above the ECEL action level (1-ppm 8-hour TWA) and above the EPA STEL
(16 ppm 15-minute TWA) and that the data represent the highest
methylene chloride exposures likely to occur under reasonably
foreseeable conditions of manufacturing, processing, use, or disposal,
as applicable, including handling of methylene chloride during those
activities. The oldest objective data used to demonstrate that
exposures are below the ECEL action level and EPA STEL will indicate
the beginning of the 5-year cycles of recurring initial exposure
monitoring as described in this Unit;
    (ii) Where potentially exposed persons are exposed to methylene
chloride for fewer than 30 days per year and the owner or operator has
measurements by direct-metering devices that give immediate results and
provide sufficient information regarding potentially exposed persons'
exposures to determine and implement the control measures that are
necessary to reduce exposures to below the ECEL action level and EPA
STEL.
    As described in more detail later in this Unit, unlike the OSHA
standards in 29 CFR 1910.1052(d)(2) to (d)(3), the owner or operator
must conduct an initial monitoring at least once every 5 years since
its last monitoring. This new initial monitoring would have to be
representative of all the potentially exposed persons in the workplace
and the tasks that they are expected to do. Additionally, if a facility
were to

commence one or more conditions of use listed in Unit IV.A.1.a. after
the effective date of the rule, the owner or operator would be required
to perform initial exposure monitoring within 180 days and would be
required to, at a minimum, conduct initial exposure monitoring every 5
years thereafter if methylene chloride is present in the facility. EPA
is soliciting comments regarding the proposed requirement for recurring
5-year initial exposure monitoring.
iii. Periodic Exposure Monitoring
    EPA's proposal is aligned with elements of the existing OSHA
standard (29 CFR 1910.1052(d)(3)) to the extent possible. Based on the
results from the initial exposure monitoring, EPA is proposing the
following periodic monitoring for owners or operators. These proposed
requirements are also outlined in Table 1.
     If all samples taken during the initial exposure
monitoring reveal: a concentration below the ECEL action level (1 ppm
8-hour TWA) and at or below the EPA STEL (16 ppm 15-minute TWA), the
ECEL and EPA STEL periodic monitoring would not be required, except
when additional exposure monitoring (Unit IV.A.1.c.v.) measurements
require it.
     If the initial exposure monitoring concentration is: below
the ECEL action level (1 ppm 8-hour TWA) and above the EPA STEL (16 ppm
15-minute TWA), the ECEL periodic monitoring would not be required
except when additional monitoring (Unit IV.A.1.c.v.) measurements
require it, but EPA STEL periodic monitoring would be required every 3
months.
     If the initial exposure monitoring concentration is: at or
above the ECEL action level (1 ppm 8-hour TWA) and at or below the ECEL
(2 ppm 8-hour TWA), and at or below the EPA STEL (16 ppm 15-minute
TWA), the ECEL would be required to be monitored every 6 months.
     If the initial exposure monitoring concentration is: at or
above the ECEL action level (1 ppm 8-hour TWA) and at or below the ECEL
(2 ppm 8-hour TWA), and above the EPA STEL, the ECEL would be required
to be monitored every 6 months and EPA STEL would be required to be
monitored every 3 months.
     If the initial exposure monitoring concentration is: above
the ECEL (2 ppm 8-hour TWA) and below, at, or above the EPA STEL (16
ppm 15-minute TWA), the ECEL and EPA STEL would be required to be
monitored every 3 months.
     The owner or operator would be permitted to alter the
periodic exposure monitoring frequency from every 3 months to every 6
months if two consecutive monitoring events taken at least 7 days apart
indicate that the potential exposure has decreased to or below the
ECEL, but at or above the ECEL action level.
     The owner or operator would be permitted to transition
from the periodic exposure monitoring frequency of every 6 months to an
initial exposure monitoring frequency of once every 5 years if two
consecutive monitoring events taken at least 7 days apart indicate that
the potential exposure has decreased below the ECEL action level and at
or below the EPA STEL. The second consecutive monitoring event would
delineate the new date from which the next 5-year initial exposure
monitoring must occur.
    In addition to the periodic monitoring standards described earlier,
EPA is proposing two additional provisions:
     Based on its monitoring results, if the owner or operator
would be required to monitor either the ECEL or EPA STEL in a 3-month
interval but does not engage in any of the conditions of use listed in
Unit IV.A.1.a. for which the WCPP is proposed over the entirety of
those 3 months, the owner or operator would be permitted to forgo the
upcoming periodic monitoring event. However, documentation of cessation
of use of methylene chloride would be required, and initial monitoring
would be required when the owner or operator resumes or starts any of
the conditions of use listed in Unit IV.A.1.a. for which the WCPP is
proposed.
     Based on its monitoring results, if the owner or operator
would be required to monitor the ECEL in a 6-month interval but does
not engage in any of the conditions of use listed in Unit IV.A.1.a. for
which the WCPP is proposed over the entirety of those 6 months, the
owner or operator would be permitted to forgo the upcoming periodic
monitoring event. However, documentation of cessation of use of
methylene chloride would be required, and initial monitoring would be
required when the owner or operator resumes or starts any of the
conditions of use listed in Unit IV.A.1.a. for which the WCPP is
proposed.
     Initial monitoring would be required to occur at least
once every 5 years if methylene chloride is present. EPA requests
comment on the timeframes for periodic monitoring outlined in this
Unit, particularly whether more frequent monitoring may be possible or
recommended.

   Table 1--Periodic Monitoring Requirements Based on Initial Exposure
                           Monitoring Results
------------------------------------------------------------------------
      Air concentration condition        Periodic monitoring requirement
------------------------------------------------------------------------
If the initial exposure monitoring       ECEL and EPA STEL periodic
 concentration is below the ECEL action   monitoring not required.
 level and at or below the EPA STEL.
If the initial exposure monitoring       ECEL monitoring not required
 concentration is below the ECEL action   and EPA STEL monitoring
 level and above the EPA STEL.            required every 3 months.
If the initial exposure monitoring       ECEL monitoring every 6 months.
 concentration is at or above the ECEL
 action level and at or below the ECEL;
 and at or below the EPA STEL.
If the initial exposure monitoring       ECEL monitoring every 6 months
 concentration is at or above the ECEL    and EPA STEL monitoring every
 action level and at or below the ECEL;   3 months.
 and above the EPA STEL.
If the initial exposure monitoring       ECEL monitoring every 3 months
 concentration is above the ECEL and      and EPA STEL monitoring every
 below, at, or above the EPA STEL.        3 months.
Two consecutive monitoring events have   Reduce periodic monitoring
 taken place 7 days apart that indicate   frequency from every 3 months
 that potential exposure has decreased    to every 6 months.
 from above the ECEL to at or below the
 ECEL, but at or above the ECEL action
 level.
Two consecutive monitoring events have   Transition from periodic
 taken place 7 days apart that indicate   monitoring frequency of every
 that potential exposure has decreased    6 months to initial monitoring
 to below the ECEL action level and at    once every 5 years. The second
 or below the EPA STEL.                   consecutive monitoring event
                                          will delineate the new date
                                          from which the next 5-year
                                          initial exposure monitoring
                                          must occur.

If the owner or operator engages in any  The owner or operator may forgo
 of the conditions of use for which       the upcoming periodic
 WCPP is proposed and is required to      monitoring event. However,
 monitor either the ECEL or EPA STEL in   documentation of cessation of
 a 3-month interval, but does not         manufacture, processing, use,
 engage in any of those conditions of     or disposal of methylene
 use for the entirety of the 3-month      chloride must be maintained,
 interval.                                and initial monitoring would
                                          be required when the owner or
                                          operator resumes or starts any
                                          of the conditions of use for
                                          which the WCPP is proposed.
Owner or operator engages in any of the  The owner or operator may forgo
 conditions of use for which WCPP is      the upcoming periodic
 proposed and is required to monitor      monitoring event. However,
 the ECEL in a 6-month interval, but      documentation of cessation of
 does not engage in any of those          manufacture, processing, use,
 conditions of use for the entirety of    or disposal of methylene
 the 6-month interval.                    chloride must be maintained,
                                          and initial monitoring would
                                          be required when the owner or
                                          operator resumes or starts any
                                          of the conditions of use for
                                          which the WCPP is proposed.
------------------------------------------------------------------------
Note: Additional scenarios in which monitoring may be required are
  discussed in Unit IV.A.1.c.v.

iv. Minimum Frequency of Exposure Monitoring
    EPA is proposing to require that an initial monitoring event be
conducted at a minimum frequency of every 5 years by owners or
operators using methylene chloride for any condition of use subject to
the WCPP. This in contrast to OSHA's standards in 1910.1052(d)(2) to
(d)(3) whereby employers would otherwise be permitted to discontinue
monitoring indefinitely based on monitoring results. Moreover, EPA is
proposing that monitoring requirements could only be made less frequent
based on the results of the initial exposure monitoring or the periodic
exposure monitoring outlined under Unit IV.A.1.c.iii.
    OSHA's standards in 1910.1052(d)(2)(i) through (iii) allow for a
discontinuation of initial monitoring which subsequently precludes the
need for periodic monitoring unless additional monitoring is required
under certain conditions. Given the steep dose response for methylene
chloride that may lead up to and include fatalities as a result of
inhalation exposure, EPA is instead proposing to require that a minimum
initial monitoring frequency be established at 5-year intervals. EPA is
requesting public comments on the proposed conditions for periodic
monitoring for methylene chloride as part of implementation of the WCPP
that differ from OSHA's existing monitoring requirements under 29 CFR
1910.1052.
v. Additional Exposure Monitoring
    In addition to initial and periodic monitoring, there are some
additional circumstances that would require a new initial exposure
monitoring. EPA is proposing that the owner or operator complying with
the WCPP would carry out this additional exposure monitoring (analogous
to those requirements outlined in 29 CFR 1910.1052(d)(4)) after any
change that may reasonably be expected to introduce additional sources
of exposure, or result in a change in exposure levels, to methylene
chloride. Examples include changes in the production, production
volume, use rate, process, control equipment, or work practices that
may reasonably be anticipated to cause additional sources of exposure
or result in increased exposure levels to methylene chloride; and
start-up, shutdown, or malfunction of the facility or facility
equipment that may reasonably be anticipated to cause additional
sources of exposure or result in increased exposure levels to methylene
chloride. This additional exposure monitoring event may result in
increased frequency of periodic monitoring. The required additional
exposure monitoring should not delay implementation of any necessary
cleanup or other remedial action to reduce the exposures to potentially
exposed persons.
d. Exposure Control Plan (ECP)
    EPA recommends and encourages the use of pollution prevention as a
means of controlling exposures whenever practicable. Pollution
prevention, also known as source reduction, is any practice that
reduces, eliminates, or prevents pollution at its source (e.g.,
elimination and substitution, as described in the hierarchy of
controls). While the WCPP is intended to be non-prescriptive to allow
more flexibility to regulated entities than requiring specific
prescriptive controls, EPA is proposing to require the use of
elimination and substitution, followed by the use of engineering
controls, administrative controls, and work practices prior to
requiring the use of respirators as a means of controlling inhalation
exposures below EPA's ECEL or STEL, in accordance with the hierarchy of
controls. If an owner or operator chooses to replace methylene chloride
with a substitute, EPA recommends that they carefully review the
available hazard and exposure information on the potential substitutes
to avoid a substitute chemical that might later be found to present
unreasonable risks or be subject to regulation (sometimes referred to
as a ``regrettable substitution''). EPA expects that, for conditions of
use for which EPA is proposing a WCPP, compliance at most workplaces
would be part of an established industrial hygiene program that aligns
with the hierarchy of controls. Workplaces that cannot, in accordance
with that hierarchy, eliminate the source of methylene chloride
emissions or replace methylene chloride with a substitute would be
required to use feasible engineering controls, and subsequently
feasible administrative controls, to implement process changes to
reduce exposures following the hierarchy of controls (Ref. 9). EPA also
expects those owners or operators already implementing the OSHA PEL of
25 ppm as an 8-hour TWA would revise their monitoring program to follow
EPA's ECEL requirements with EPA's lower ECEL of 2 ppm as an 8-hour TWA
and EPA's STEL of 16 ppm as a 15-minute TWA.
    Analogous to the OSHA Standard (29 CFR 1910.1052(e)), EPA is
proposing to require that the owner or operator demarcate any area
where airborne concentrations of methylene chloride are reasonably
expected to exceed the ECEL or the EPA STEL. This regulated area would
be demarcated using administrative controls, e.g., highly visible
signifiers, in multiple languages as appropriate, placed in conspicuous
areas, and documented through training and recordkeeping. The owner or
operator would be required to restrict access to the regulated area
from any potentially exposed person that lacks proper training or is
otherwise unauthorized to enter.
    EPA proposes to require regulated entities use the hierarchy of
controls to the extent feasible and supplement

further protections using PPE, including respirators for potentially
exposed persons at risk of inhalation exposure above the ECEL or EPA
STEL. If efforts of elimination, substitution, engineering controls,
and administrative controls are not sufficient to reduce exposures to
or below the ECEL or EPA STEL for all potentially exposed persons in
the workplace, EPA proposes to require the owner or operator to use
feasible controls (including elimination, substitution, engineering
controls, or administrative controls and work practices) to reduce
methylene chloride concentrations in the workplace to the lowest levels
achievable and, analogous to the requirements under 29 CFR
1910.1052(e)(3), supplement these controls with respiratory protection
and PPE as needed to achieve the ECEL before potentially exposed
persons enter a regulated area. In such cases, EPA would require that
the owner or operator provide potentially exposed persons reasonably
likely to be exposed to methylene chloride by inhalation to
concentrations above the ECEL or EPA STEL with respirators affording
sufficient protection against inhalation risk and appropriate training
on the proper use of such respirators, to ensure that their exposures
do not exceed the ECEL or EPA STEL, as described in this Unit.
    EPA also proposes to require that the owner or operator document
their efforts to use elimination, substitution, engineering controls,
and administrative controls to reduce exposure to or below the ECEL or
EPA STEL in an exposure control plan. In addition, analogous to the
requirements under 29 CFR 1910.1052(f)(2), an owner or operator would
be prohibited from rotating work schedules to comply with the ECEL 8-
hour TWA.
    EPA proposes to require that the owner or operator include and
document in the exposure control plan or through any existing
documentation of the facility's safety and health program developed as
part of meeting OSHA requirements or other safety and health standards
the following:
    (i) Identification of available exposure controls and rationale for
using or not using available exposure controls in the following
sequence (i.e., elimination and substitution, then engineering controls
and administrative controls) to reduce exposures in the workplace to
either at or below the ECEL or to the lowest level achievable, and the
exposure controls selected based on feasibility, effectiveness, and
other relevant considerations;
    (ii) If exposure controls were not selected, document the efforts
identifying why these are not feasible, not effective, or otherwise not
implemented;
    (iii) Actions taken to implement exposure controls selected,
including proper installation, maintenance, training, or other steps
taken;
    (iv) Regular inspections, evaluations, and updating of the exposure
controls to ensure effectiveness and confirmation that all persons are
using them accordingly;
    (v) Occurrence and duration of any start-up, shutdown, or
malfunction of exposure controls or of facility equipment that causes
air concentrations above the ECEL or EPA STEL and subsequent corrective
actions taken during start-up, shutdown, or malfunctions to mitigate
exposures to methylene chloride; and
    (vi) Objective data generated during the previous 5 years, when
used to forgo the initial exposure monitoring, must include: the use of
methylene chloride being evaluated, the source of objective data,
measurement methods, measurement results, and measurement analysis of
the use of methylene chloride, and any other relevant data to the
operations, processes, or person's exposure.
e. Personal Protective Equipment (PPE)
    Where elimination, substitution, engineering, and administrative
controls are not feasible or sufficiently protective to reduce the air
concentration to or below the ECEL, or if inhalation exposure above the
ECEL is still reasonably likely, EPA proposes to set minimum
respiratory PPE requirements based on an owner or operator's measured
air concentration for one or more potentially exposed persons and the
level of PPE needed to reduce exposure to or below the ECEL. In those
circumstances, EPA is proposing to require that the owner or operator
also comply with OSHA's General Requirements for PPE standard at 29 CFR
1910.132 for application of a PPE program. EPA is also proposing that
the owner or operator comply with 29 CFR 1910.134 for proper use,
maintenance, fit-testing, and training of respirators. EPA recognizes
that there may be limitations in using certain types of PPE or
respirator protection for various work scenarios such as cost, time
burdens, ergonomic and dexterity considerations, climate, size, and
capability.
i. Required Dermal Protection
    EPA is proposing to require provision and use of chemically
resistant gloves in combination with specific activity training (e.g.,
glove selection (type, material), expected duration of glove
effectiveness, actions to take when glove integrity is compromised,
storage requirements, procedure for glove removal and disposal,
chemical hazards) for tasks where dermal exposure can be expected to
occur. Additionally, EPA is proposing to require owners and operators
to continue to comply with relevant sections of the methylene chloride
OSHA standard to minimize and protect potentially exposed persons from
dermal exposure, including 29 CFR 1910.1052(h) and (i). Additional
information related to choosing appropriate gloves can be found in the
NIOSH Hazard Alert (Ref. 35) and in appendix F of the 2020 Risk
Evaluation for Methylene Chloride (Ref. 1). EPA requests comment on the
degree to which additional guidance related to use of gloves might be
necessary. Additionally, EPA requests comment on whether EPA should
specifically incorporate dermal protection into the exposure control
plan and require consideration of the hierarchy of controls for dermal
exposures.
ii. Required Respiratory Protection
    EPA is proposing the following requirements for respiratory
protection, based on the exposure monitoring concentrations measured as
an 8-hour TWA that exceeds the ECEL (2 ppm) or 15-minute TWA that
exceeds the EPA STEL (16ppm); see also the following table (Table 2).
These requirements would apply after all other feasible controls are
exhausted or proven ineffective to control inhalation exposure
(including elimination, substitution, engineering controls, and
administrative controls in accordance with the hierarchy of controls).
EPA is proposing to establish minimum respiratory protection
requirements, such that any respirator affording the same or a higher
degree of protection than the following proposed requirements may be
used. While this Unit includes respirator selection requirements for
respirators of Assigned Protection Factor (APF) of 1,000 or greater,
EPA does not anticipate that respirators beyond APF 25 will be widely
or regularly used to address unreasonable risk, particularly when other
controls are put in place. EPA anticipates that owners or operators
would attempt to minimize respirator costs by reducing inhalation
exposures levels so that, if a respirator is needed, a supplied-air
respirator could be used in lieu of a self-contained breathing
apparatus. Under this proposed regulatory option, as with existing OSHA
regulations, air-purifying respirators (in contrast to air-supplied

respirators) would not be permitted as a means of mitigating methylene
chloride exposure, as they do not provide adequate respiratory
protection against this chemical (Ref. 36). Additionally, EPA
acknowledges in Unit V.A.1. that there may be respirator limitations
dependent upon the nature of the activity in which methylene chloride
is used (e.g., a decreased range of motion or access to a small space
could hinder PPE use).
     If the measured exposure concentration is at or below the
ECEL (2 ppm 8-hour TWA) and EPA STEL (16 ppm 15-minute TWA): no
respiratory protection would be required.
     If the measured exposure concentration is above 2 ppm and
less than or equal to 50 ppm (25 times the ECEL): the respirator
protection required would be any NIOSH-certified supplied-air
respirator (SAR) or airline respirator in a continuous-flow mode
equipped with a loose-fitting facepiece or helmet/hood (APF 25).
     If the measured exposure concentration is above 50 ppm and
less than or equal to 100 ppm (50 times the ECEL): the respirator
protection required would be: (i) Any NIOSH-certified Supplied-Air
Respirator (SAR) or airline respirator in a demand mode equipped with a
full facepiece (APF 50); or (ii) Any NIOSH-certified Self-Contained
Breathing Apparatus (SCBA) in demand-mode equipped with a full
facepiece or helmet/hood (APF 50).
     If the measured exposure concentration is unknown or at
any value above 100 ppm and up to 2,000 ppm (1,000 times the ECEL): the
respirator protection required would be: (i) Any NIOSH-certified
Supplied-Air Respirator (SAR) or Airline Respirator in a continuous-
flow mode equipped with a full facepiece or certified helmet/hood (APF
1,000); or (ii) Any NIOSH-certified Supplied-Air Respirator (SAR) or
Airline Respirator in pressure-demand or other positive-pressure mode
equipped with a full facepiece (APF 1,000); or (iii) Any NIOSH-
certified Self-Contained Breathing Apparatus (SCBA) in a pressure-
demand or other positive-pressure mode equipped with a full facepiece
or certified helmet/hood (APF 1,000+).

       Table 2--Respiratory Protection Conditions and Requirements
------------------------------------------------------------------------
                                         Minimum required respirator
      Concentration condition                    protection
------------------------------------------------------------------------
At or below the ECEL and EPA STEL.  No respirator required.
Above ECEL (2 ppm) and less than    Any NIOSH-certified supplied-air
 or equal to 50 ppm (25 times the    respirator (SAR) or airline
 ECEL).                              respirator in a continuous-flow
                                     mode equipped with a loose-fitting
                                     facepiece or helmet/hood (APF 25).
Above 50 ppm and less than or       Either (i) any NIOSH-certified
 equal to 100 ppm (50 times the      Supplied-Air Respirator (SAR) or
 ECEL).                              airline respirator in a demand mode
                                     equipped with a full facepiece (APF
                                     50); or (ii) any NIOSH-certified
                                     Self-Contained Breathing Apparatus
                                     (SCBA) in demand-mode equipped with
                                     a full facepiece or helmet/hood
                                     (APF 50).
Unknown concentration or at any     One of (i) any NIOSH-certified
 value above 100 ppm and up to       Supplied-Air Respirator (SAR) or
 2,000 ppm (1,000 times the ECEL).   Airline Respirator in a continuous-
                                     flow mode equipped with a full
                                     facepiece or certified helmet/hood
                                     (APF 1,000); or (ii) any NIOSH-
                                     certified Supplied-Air Respirator
                                     (SAR) or Airline Respirator in
                                     pressure-demand or other positive-
                                     pressure mode equipped with a full
                                     facepiece (APF 1,000); or (iii) any
                                     NIOSH-certified Self-Contained
                                     Breathing Apparatus (SCBA) in a
                                     pressure-demand or other positive-
                                     pressure mode equipped with a full
                                     facepiece or certified helmet/hood
                                     (APF 10,000).
------------------------------------------------------------------------

f. Additional Proposed Requirements
i. Workplace Participation
    EPA encourages owners and operators to consult with potentially
exposed persons on the development and implementation of exposure
control plans and PPE/respirator programs. EPA is proposing to require
owners and operators to provide potentially exposed persons regular
access to the exposure control plans, exposure monitoring records, PPE
program implementation, and respirator program implementation (such as
fit-testing and other requirements) described in 29 CFR 1910.134(l). To
ensure compliance in workplace participation, EPA is proposing that the
owner or operator document the notice to and ability of any potentially
exposed person that may reasonably be affected by methylene chloride
inhalation exposure to readily access the exposure control plans,
facility exposure monitoring records, PPE program implementation, or
any other information relevant to methylene chloride inhalation
exposure in the workplace.
ii. Notification of Monitoring Results
    EPA proposes that when a potentially exposed person's exposure to
methylene chloride exceeds the ECEL action level within a regulated
area, the owner or operator would be required to inform each
potentially exposed person of the quantity, location, manner of use,
release, and storage of methylene chloride and the specific operations
in the workplace that could result in exposure to methylene chloride,
particularly noting where exposures may be above the ECEL or EPA STEL,
analogous to those requirements outlined in 29 CFR 1910.1052(l). EPA
proposes that the owner or operator must, within 15 working days after
receipt of the results of any exposure monitoring, notify each
potentially exposed person whose exposure is represented by that
monitoring in writing, either individually to each potentially exposed
person or by posting the information in an appropriate and accessible
location, such as public spaces or common areas, for potentially
exposed persons outside of the regulated area (as described in Unit
IV.A.1.d.). The notice would be required to identify the ECEL, ECEL
action level, and EPA STEL and what they mean in plain language, the
exposure monitoring results, and any corresponding respiratory
protection required. The notice would also be required to include a
description of the actions taken by the owner or operator to reduce
inhalation exposures to or below the ECEL, or refer to a document
available to the potentially exposed persons which states the actions
to be taken to reduce exposures, and to be posted in multiple languages
if necessary (e.g., notice must be in a language that the potentially
exposed person understands, including a non-English language version
representing the language of the largest group of workers who cannot
readily comprehend or read English). While 15 working days is
consistent with requirements under the OSHA methylene chloride
standard, EPA notes that it may be preferable to require more expedient
notification of monitoring results, and that precedent exists in some
circumstances for faster

notification timeframes (e.g., OSHA requirements for the construction
sector require a 5-day timeframe). EPA therefore requests comment on
the 15-day timeframe for notification of potentially exposed persons of
monitoring results and the possibility for a shorter timeframe, such as
5 days.
iii. Recordkeeping
    For each monitoring event of methylene chloride, OSHA requires
under 29 CFR 1910.1052(m) that the employer record information
including, but not limited to, dates; operations involving exposure;
sampling and analytical methods; the number of samples; durations, and
results of each sample taken; the type of respirator and PPE worn (if
any); the exposed employees' names, work shifts, and job
classifications; and exposure of all the employees represented by
monitoring, indicating which potentially exposed persons were actually
monitored. EPA is requiring that this information is kept by the owner
or operator of record for potentially exposed persons. In addition to
the requirements outlined in 29 CFR 1910.1052(m)(2), EPA is proposing
to require documentation of the following whenever monitoring for the
WCPP is required under TSCA section 6(a):
    (i) All measurements that may be necessary to determine the
conditions (e.g., work site temperatures, humidity, ventilation rates,
monitoring equipment type and calibration dates) that may affect the
monitoring results;
    (ii) All other potentially exposed persons whose exposure
monitoring was not measured but whose exposure is intended to be
represented by the area or representative sampling monitoring;
    (iii) Use of established analytical methods such as those outlined
in appendix A of the ECEL memo (Ref. 11) with a limit of detection
below the ECEL action level and accuracy of monitoring within 25% for
the ECEL and 35% for the EPA STEL, as discussed in Unit IV.A.1.c.ii.,
so that the owner or operator may identify when the implementation of
additional exposure controls is necessary, determine the monitoring
frequency according to the requirements described in this Unit, and
properly identify and provide persons exposed to methylene chloride
with the required respiratory equipment and PPE proposed in this Unit;
    (iv) Compliance with the Good Laboratory Practice Standards at 40
CFR part 792;
    (v) Information regarding air monitoring equipment, including:
type, maintenance, calibrations, performance tests, limits of
detection, and any malfunctions.
    For owners and operators to demonstrate compliance with the WCPP
provisions, EPA is proposing that owners and operators must retain
compliance records for 5 years, unless a longer retention time is
required under 29 CFR 1910.1020, or other applicable regulations. EPA
is requiring the owner or operator to retain records of:
     Exposure control plan;
     Regulated areas and authorized personnel;
     Facility exposure monitoring records;
     Notifications of exposure monitoring results;
     PPE and respiratory protection used and program
implementation; and
     Information and training required under 29 CFR 1910.1052
section (l) and appendix A, provided by the owner or operator to each
potentially exposed person prior to or at the time of initial
assignment to a job involving potential exposure to methylene chloride.
    All records required to be maintained by this Unit could be kept in
the most administratively convenient form (electronic or paper). The
owner or operator would be required to document training or re-training
(analogous to 29 CFR 1910.1052(l)(5)) of any potentially exposed person
as necessary to ensure that, in the event of monitoring results that
indicate exposure or possible exposures above the ECEL action level or
the EPA STEL, the potentially exposed person has demonstrated
understanding of how to safely use and handle methylene chloride and
how to appropriately use required PPE. EPA expects that the content of
such training will not exceed what is already required by 29 CFR
1910.1052 section (l) and appendix A. In addition, the owner or
operator would be required to update the training and requisite
documentation when there is reasonable expectation that exposure may
exceed the ECEL action level due to change in tasks or procedures.
g. Compliance Timeframes
    With regard to the compliance timeframe for those occupational
conditions of use which are subject to the WCPP, EPA is proposing to
require that owners and operators establish initial exposure monitoring
according to the process outlined in this Unit by [DATE 180 DAYS AFTER
DATE OF PUBLICATION OF FINAL RULE IN THE FEDERAL REGISTER]. EPA is
proposing to require each owner or operator ensure that the airborne
concentration of methylene chloride does not exceed the ECEL or EPA
STEL for all potentially exposed persons by [DATE 270 DAYS AFTER DATE
OF PUBLICATION OF FINAL RULE IN THE FEDERAL REGISTER], and if
applicable, each owner or operator must provide respiratory protection
sufficient to reduce inhalation exposures to below the ECEL or EPA STEL
to all potentially exposed persons in the regulated area within 3
months after receipt of the results of any exposure monitoring or
within 9 months after the date of publication of the final rule in the
Federal Register (for any new facilities, or a facility commencing one
or more conditions of use listed in Unit IV.A.1.a. after the effective
date of the final rule, the timeframe for the requirement for initial
exposure monitoring is described earlier in Unit IV.A.1.c.ii.;
following that, the requirements and timeframes in this Unit would
apply). EPA is also proposing to require owners and operators demarcate
a regulated area within 3 months after receipt of any exposure
monitoring that indicates exposures exceeding the ECEL or EPA STEL.
Owners and operators should proceed accordingly to implement an
exposure control plan by [DATE 360 DAYS AFTER DATE OF PUBLICATION OF
FINAL RULE IN THE FEDERAL REGISTER]. EPA requests comment relative to
the ability of owners or operators to conduct initial monitoring by
[DATE 180 DAYS AFTER DATE OF PUBLICATION OF FINAL RULE IN THE FEDERAL
REGISTER], and anticipated timelines for any procedural adjustments
needed to comply with the requirements outlined in this Unit. EPA may
finalize shorter or longer compliance timeframes based on public
comment.
2. Prohibition of Certain Industrial and Commercial Uses
    Except for those uses which will continue under the WCPP, EPA is
proposing to prohibit industrial and commercial use of methylene
chloride, including use of methylene chloride in: solvent for batch
vapor degreasing; solvent for in-line vapor degreasing; solvent for
cold cleaning; solvent for aerosol spray degreaser/cleaner; adhesives,
sealants, and caulks; paints and coatings; paint and coating removers
(including furniture refinishers); adhesive and caulk removers; metal
aerosol degreasers; metal non-aerosol degreasers; finishing products
for fabric, textiles and leather; automotive care products (functional
fluids for air conditioners); automotive care products (interior car
care); automotive care products (degreasers); apparel and footwear care
products; spot removers for apparel and textiles; liquid lubricants and
greases; spray lubricants and greases; aerosol

degreasers and cleaners; non-aerosol degreasers and cleaners; cold pipe
insulations; solvent that becomes part of a formulation or mixture;
processing aid; propellant and blowing agent; electrical equipment,
appliance, and component manufacturing; plastic and rubber products
manufacturing; cellulose triacetate film production; anti-spatter
welding aerosol; oil and gas drilling, extraction, and support
activities; toys, playground and sporting equipment; carbon remover,
wood floor cleaner, and brush cleaner; and lithographic printing plate
cleaner. This does not include manufacturing and processing of
methylene chloride for commercial use or industrial and commercial use
of methylene chloride as a laboratory chemical, for which EPA is
proposing to require compliance with a WCPP for the reasons described
in Unit III.B.3. This rationale is discussed further in Unit V.A.1.
    As Discussed in Unit III.B.1.f., the restrictions in this proposed
rule do not apply to any substance that is excluded from the definition
of ``chemical substance'' under TSCA section 3(2)(B)(ii) through (vi).
However, EPA requests comment on the impacts, if any, the proposed
prohibition described in this Unit, or other aspects of this proposal,
may have on the production and availability of any food, food additive,
drug, cosmetic, device, or other substance excluded from the definition
of ``chemical substance'' under TSCA section 3(2)(B)(ii) through (vi).
    As discussed in Unit III.B.3., based on consideration of
alternatives, the broad range of work environments and activities, and
the severity of the hazards of methylene chloride, EPA determined that
prohibition is the best way to address the unreasonable risk from
methylene chloride driven by the conditions of use identified in this
Unit. EPA requests comment regarding the number of entities that could
potentially close as well as associated costs with a prohibition of
methylene chloride for certain industrial and commercial conditions of
use identified in this Unit. EPA would also like comment on whether it
should consider a de minimis level of methylene chloride in
formulations for certain continuing industrial and commercial uses to
account for impurities (e.g., 0.1% or 0.5%) when finalizing the
prohibitions described in this Unit, and, if so, what level should be
considered de minimis.
    EPA is proposing that the prohibition for uses described in this
section would become effective following prohibitions relevant to these
uses in stages of the supply chain before the industrial and commercial
use (e.g., manufacturing and processing). This proposal includes
restrictions in a staggered schedule for each stage of the supply chain
and would come into effect in 90 days for manufacturers, 180 days for
processors, 270 days for distributors to retailers, 360 days for all
other distributors and retailers, and 450 days for industrial and
commercial uses after the publication date of the final rule. When
proposing these compliance dates, EPA considered sustained awareness of
risks, including acute fatalities, resulting from methylene chloride
exposure as well as precedent established by the OSHA standards (62 FR
1494, January 10, 1997). EPA has no information indicating that the
proposed compliance dates are not practicable for the activities that
would be prohibited, or that additional time is needed for products
affected by the proposed restrictions to clear the channels of trade.
However, EPA requests comment on whether additional time is needed, for
example, for products affected by proposed restrictions to clear the
channels of trade. EPA may finalize shorter or longer compliance
timeframes based on public comment.
    Additionally, EPA recognizes that there may be instances where an
ongoing use of methylene chloride that has implications for national
security or critical infrastructure as it relates to other Federal
agencies (e.g., DOD, NASA) is identified after the methylene chloride
rule is finalized, but the final rule prohibits that use. For instances
like that, EPA requests comments on an appropriate, predictable process
that could expedite reconsideration for uses that Federal agencies or
their contractors become aware of after the final rule is issued using
the tools available under TSCA, aligning with the requirements of TSCA
section 6(g). One example of an approach could be the establishment by
rulemaking of a Federal agency category of use that would require
implementation of the WCPP and periodic reporting to EPA on details of
the use as well as progress in discontinuing the use or finding a
suitable alternative. To utilize the category of use a Federal agency
would petition EPA, supported by documentation describing the specific
use (including documentation of the specific need, service life of any
relevant equipment, and specific identification of any applicable
regulatory requirements or certifications, as well as the location and
quantity of the chemical being used); the implications of cessation of
this use for national security or critical infrastructure (including
how the specific use would prevent injuries/fatalities or otherwise
provide life-supporting functions); exposure control plan; and, for
Federal agency uses where similar adoption by the commercial sector may
be likely, concrete steps taken to identify, test, and qualify
substitutes for the uses (including details on the substitutes tested
and the specific certifications that would require updating; and
estimates of the time required to identify, test, and qualify
substitutes with supporting documentation). EPA requests comment on
whether these are the appropriate types of information for use in
evaluating this type of category of use, and whether there are other
considerations that should apply. EPA would make a decision on the
petition within 30 days and publish the decision in the Federal
Register shortly after. Additionally, during the year following the
petition, EPA would take public comment on the approved petition and no
later than 180 days after submitting the petition to EPA, the
requesting agency would submit monitoring data indicating compliance
with the WCPP at each relevant location as well as documentation of
efforts to identify or qualify substitutes. In the absence of that
confirmatory data, the utilization of the generic Federal agency
category of use would expire within one year of the date of receipt by
EPA of the petition. EPA could undertake a TSCA section 6(g) rulemaking
for those instances where the Federal agency could not demonstrate
compliance with the WCPP. This is just one example of a potential
process. EPA requests comments on a process that could expedite
reconsideration for uses that Federal agencies or their contractors
become aware of after the final rule is issued.
3. Prohibition of Manufacturing, Processing, and Distribution of
Methylene Chloride for Consumer Use
    In the 2020 Risk Evaluation for Methylene Chloride, EPA evaluated
consumer use of methylene chloride: as a solvent in aerosol spray
degreasers/cleaners; in adhesives and sealants in single component
glues and adhesives and sealants in caulks; in paints and coatings in
brush cleaners and in adhesive/caulk removers; in metal products in
aerosol and non-aerosol degreasers and cleaners; in automotive care
products in functional fluids for air conditioners and in degreasers;
in lubricants and greases in liquid and spray lubricants and greasers
and in aerosol and non-aerosol degreasers and cleaners; in building and
construction

materials in cold pipe insulation; in arts, crafts, and hobby materials
in crafting glue and cement/concrete; and in other uses such as anti-
spatter welding aerosol and in carbon remover and brush cleaner. All
consumer uses evaluated in the 2020 Risk Evaluation for Methylene
Chloride drive unreasonable risk of injury to health. As such, for
purposes of this risk management rulemaking, ``consumer use'' refers to
all known, intended, or reasonably foreseen methylene chloride consumer
uses. EPA is proposing to prohibit the manufacturing, processing, and
distribution in commerce of methylene chloride for all consumer use.
(The proposed prohibitions would not extend to the use of methylene
chloride in consumer paint and coating removers since that use was not
evaluated in the 2020 Risk Evaluation for Methylene Chloride and
manufacturing, processing, and distribution for that use are already
prohibited. (84 FR 11420 (March 27, 2019)).
    As discussed in Unit III.B.3., based on consideration of the
severity of the hazards of methylene chloride in conjunction with the
limited options available to adequately address the identified
unreasonable risk to consumers and bystanders under TSCA section 6(a),
EPA is proposing to address the unreasonable risk from consumer use by
prohibiting the manufacturing (including import), processing, and
distribution in commerce of methylene chloride for consumer use in
order to remove methylene chloride and products containing methylene
chloride from the market, thereby effectively eliminating instances of
consumer use.
    Additionally, EPA is proposing to prohibit retailers from
distributing in commerce methylene chloride and all methylene chloride-
containing products, in order to prevent products intended for
industrial and commercial use under the WCPP outlined in Unit IV.A.1.
from being purchased by consumers. A retailer is any person or business
entity that distributes or makes available products to consumers,
including through e-commerce internet sales or distribution. If a
person or business entity distributes or makes available any product to
at least one consumer, then it is considered a retailer (40 CFR
751.103). For a distributor not to be considered a retailer, the
distributor must distribute or make available products solely to
commercial or industrial end-users or businesses. Prohibiting
manufacturers (including importers), processors, and distributors from
distributing methylene chloride, or any products containing methylene
chloride, to retailers would prevent retailers from making these
products available to consumers, which would help address that part of
the unreasonable risk driven by consumer use of methylene chloride
(Ref. 37). EPA promulgated a similar prohibition for retailers in the
2019 final rule addressing unreasonable risk from consumer use of
methylene chloride in Paint and Coating Removal (84 FR 11420, March 27,
2019), and has not received negative feedback from retailers regarding
sales losses. EPA has continued to receive feedback from stakeholders,
including small businesses, on particular strategies they suggest could
be used to ensure that distribution only occurs to commercial entities,
such as requiring a business number (Ref. 6). To that end, EPA would
like comment on whether distributors that are not retailers should be
required to use tax IDs or other verification methods prior to selling
methylene chloride or products containing methylene chloride to ensure
consumers are not purchasing methylene chloride or industrial or
commercial products containing methylene chloride.
    Additionally, during litigation on the 2019 final rule petitioners
argued that EPA's definition of ``retailer'' was so broad as to cover
all commercial entities, creating supply chain issues for commercial
users seeking to attain and use the chemical for commercial activities
(Lab. Council for Latin Am. Advancement v. United States Env't Prot.
Agency, 12 F.4th 234 (2d Cir. 2021)). EPA has not found this to be the
case; small businesses that are non-retail distributors exist and even
participated as small entity representatives consulted as part of the
SBAR process for this rulemaking. Nonetheless, EPA is soliciting
comment on whether similar supply chain issues for uses that are
permitted under the WCPP are anticipated.
    EPA is proposing that the prohibitions of manufacturing,
processing, and distribution in commerce of methylene chloride for
consumer use described in this section would occur in 90 days for
manufacturers, 180 days for processers, 270 days for distributing to
retailers, and 360 days for all other distributors and retailers after
the publication date of the final rule in the Federal Register. EPA
considered irreversible health effects and risks, such as acute
fatalities, associated with methylene chloride when proposing
compliance dates. EPA has no information indicating these compliance
dates are not practicable for the activities that would be prohibited,
or that additional time is needed for products affected by proposed
restrictions to clear the channels of trade. However, EPA requests
comment on whether additional time is needed, for example, for products
affected by proposed restrictions to clear the channels of trade. EPA
may finalize shorter or longer compliance timeframes based on public
comment. EPA would also like comment on whether it should consider a de
minimis level of methylene chloride in formulations for certain
continuing industrial and commercial uses to account for impurities
(e.g., 0.1% or 0.5%) when finalizing these prohibitions, and, if so,
what level should be considered de minimis.
4. Other Requirements
a. Recordkeeping
    For conditions of use that are not otherwise prohibited under this
proposed regulation, EPA is also proposing that manufacturers,
processors, and distributors maintain ordinary business records, such
as invoices and bills-of-lading, that demonstrate compliance with
restrictions and other provisions of this proposed regulation; and that
they maintain such records for a period of 5 years from the date the
record is generated. EPA notes that this 5-year record retention period
is an increase from the 3-year requirements for records related to
consumer paint and coating removal finalized in the 2019 final rule.
However, the 3-year requirement still applies to records generated
under that rule. EPA is proposing that this requirement begin at the
effective date of the rule (60 days following publication of the final
rule in the Federal Register). Recordkeeping requirements would ensure
that owners or operators can demonstrate compliance with the proposed
regulations if necessary. Note that this requirement would expand those
recordkeeping requirements promulgated in 2019 at 40 CFR 751.109
affecting manufacturers, processors, and distributors of methylene
chloride.
b. Downstream Notification
    For conditions of use that are not otherwise prohibited under this
proposed regulation, EPA is proposing that manufacturers (including
importers), processors, and distributors, excluding retailers, of
methylene chloride and methylene chloride-containing products provide
downstream notification of certain prohibitions through Safety Data
Sheets

(SDSs) by adding to sections 1(c) and 15 of the SDS the following
language:

    After [DATE 270 DAYS AFTER DATE OF PUBLICATION OF FINAL RULE IN
THE FEDERAL REGISTER], this chemical/product cannot be distributed
in commerce to retailers. After [DATE 360 DAYS AFTER DATE OF
PUBLICATION OF FINAL RULE IN THE FEDERAL REGISTER], this chemical/
product is and can only be distributed in commerce or processed for
the following purposes: (1) Processing as a reactant; (2) Processing
for incorporation into a formulation, mixture, or reaction product;
(3) Processing for repackaging; (4) Processing for recycling; (5)
Industrial or commercial use as a laboratory chemical; (6)
Industrial or commercial use as a bonding agent for acrylic and
polycarbonate in mission-critical military and space applications,
including in the production of specialty batteries for such
applications that is performed by the Department of Defense, the
Department of Homeland Security, or the National Aeronautics and
Space Administration or their contractors at locations controlled by
the agency or the agency's contractor; (7) Industrial or commercial
use for paint and coating removal from safety-critical, corrosion-
sensitive components of aircraft and spacecraft that are owned or
operated by the U.S. Department of Defense, the National Aeronautics
and Space Administration, the U.S. Department of Homeland Security,
and the Federal Aviation Administration that is performed by the
agency or agency contractors at locations controlled by the agency
or the agency's contractor; (8) Industrial or commercial use for
paint and coating removal from safety-critical, corrosion-sensitive
components of other aircraft and spacecraft until [10 years after
date of publication of the final rule in the Federal Register], and
(9) Disposal.

    The intention of downstream notification is to spread awareness
throughout the supply chain of the restrictions on methylene chloride
under TSCA as well as provide information to commercial end users about
allowable uses of methylene chloride. Note that this requirement would
amend and add to the downstream notification requirements promulgated
in 2019 at 40 CFR 751.107 for paint and coating removers for consumer
use, and additionally redesignate that section as 751.111(a). As they
become effective, the new amended requirements would supersede those
notification requirements promulgated in 2019.
    To provide adequate time to update the SDS and ensure that all
products in the supply chain include the revised SDS, EPA is proposing
a 150-day period for manufacturers and a 210-day period for processors
and distributors to implement the proposed SDS changes (following
publication of the final rule).
    EPA requests comments on the appropriateness of identified
compliance timeframes for recordkeeping and downstream notification
requirements described in this Unit.
5. TSCA Section 6(g) Exemptions
    Under TSCA section 6(g)(1), EPA may grant an exemption from a
requirement of a TSCA section 6(a) rule for a specific condition of use
of a chemical substance or mixture. TSCA section 6(g)(1)(B) permits
such an exemption if EPA finds that compliance with the requirement, as
applied with respect to the specific condition of use, would
significantly disrupt the national economy, national security, or
critical infrastructure.
    TSCA section 6(g)(2) requires EPA to analyze the need for the
exemption, and to make public the analysis and a statement describing
how the analysis was taken into account when proposing an exemption
under TSCA section 6(g). To that end, based on discussions and
information provided by industry stakeholders, EPA has analyzed the
need for different exemptions and is proposing to grant two of them,
with conditions as required under TSCA section 6(g)(4) and described in
Units IV.A.5.a.ii. and IV.A.5.b.ii. This Unit presents the results of
that analysis.
a. Uses of Methylene Chloride for Paint and Coating Removal Essential
for Critical Infrastructure
i. Analysis of the Need for TSCA Section 6(g)(1)(B) Exemption for
Commercial Aviation and Aerospace
    EPA has preliminarily determined that a prohibition on the
commercial use of methylene chloride for paint and coating removal from
safety-critical, corrosion-sensitive components of aircraft and
aerospace vehicles for commercial aviation and aerospace would
significantly disrupt the national economy and critical infrastructure.
Aviation has been designated by co-sector agencies DHS and DOT as a key
subsector in the Transportation Systems Sector, one of 16 designated
critical infrastructure sectors. There are no technically feasible
alternatives currently available for methylene chloride used in paint
and coating removal for safety-critical, corrosion-sensitive components
of aircraft and aerospace vehicles. Thus, commercial aviation and
aerospace compliance with the proposed ban on methylene chloride use in
commercial paint and coating removal would significantly disrupt
critical infrastructure.
    As explained by a commenter on the 2017 Notice of Proposed
Rulemaking (NPRM), all aircraft have similar safety-critical,
corrosion-sensitive components of the type described by DOD (Ref. 38).
For example, commercial aircraft often contain components, such as
landing gear, that are made from high-strength alloy steels. According
to this commenter, the aerospace industry, like DOD, has made
significant investments in the evaluation of alternative methods and
materials for removing coatings. The commenter states that the industry
has had some success, depending upon the substrate, surface treatment,
and coating system, but investigation continues into both chemical and
non-chemical means. Non-chemical methods, such as plastic beads, were
not suitable in all instances due to concerns about damaging the
substrate. Many alternative chemical strippers were not effective on
all coatings, which caused corrosion concerns in some cases. According
to this commenter, benzyl alcohol is a qualified alternative paint
remover for some paint formulations but cannot be considered a ``drop-
in'' replacement for all applications due to performance concerns.
    The concerns expressed by this commenter about corrosion-sensitive
components on aircraft and aerospace equipment echo the concerns over
methylene chloride alternatives expressed by DOD and discussed at
length in the preamble to EPA's 2017 proposal. For example, both the
commenter and DOD stated that currently available substitute chemicals
cannot completely remove certain coatings (Ref. 38). This results in
improperly applied, incompletely adhering replacement coatings, which
may result in corrosion of underlying critical parts. For another
example, according to the commenter and DOD, substitute chemicals are
also incompatible with some underlying metallic, nonmetallic, and
composite materials, resulting in material damage to critical
components, and the potential for an increased risk of catastrophic
failure of safety critical parts. The commenter on the 2017 NPRM also
stated that the process for evaluating and then adopting alternatives
in aviation applications is a multi-year process. According to the
commenter, the materials required to remove coatings on aircraft parts
must be developed by a material formulator to meet technical
performance requirements and must be ``qualified by the Original
Equipment Manufacturer (OEM), and then shown to not cause harm to the
aircraft or negatively affect performance to the FAA prior to
implementation'' (Ref. 38). The commenter stated that this can take
years, with no guarantee of success, so

a longer timeframe for aviation and aerospace to make the transition is
appropriate. The commenter suggested that 10 years would be a realistic
estimate of the time needed.
    More recently, Boeing provided information to EPA indicating that
the company has invested considerable resources over many years to
qualify and implement alternatives to methylene chloride, including a
combination of acid, alkaline, and hydrogen peroxide-activated benzyl
alcohol removers and plastic media blast (Ref. 31). Boeing continues to
evaluate potential alternatives, such as laser ablation, which the
company believes will, if implemented, eliminate hazardous waste,
address ergonomic challenges and save significant time over traditional
paint and coating removal operations. According to Boeing, the company
has identified several paint and coating removal applications with no
feasible alternatives to methylene chloride (Ref. 31). These include:
     Large parts or parts with complex geometries that cannot
undergo media blasting or strip tank immersion either due to size
constraints or entrapment concerns, and where hand abrasion is
impractical;
     Situations in which selective coating removal is needed,
e.g., the preservation of a conversion coating;
     Effective removal of oven-cured paints and coatings;
     Localized removal of coatings on overhaul or rework parts
to reveal part markings and serial numbers;
     Stripping of parts preceding non-destructive testing,
where other coating removal methods such as media blasting could hide
defects; and
     Removal of polyvinyl formal or polyurethane insulating
enamel from copper magnet wire.
    While there are alternatives available for many applications, the
public comments on the 2017 NPRM, and the information provided by
Boeing in 2022 demonstrate there are several aviation and aerospace
applications for which there are limited alternatives to methylene
chloride for paint and coating removal, due to concerns about damage to
the substrate, and these limited alternatives take longer to work. EPA
has preliminarily determined that lengthening the time that commercial
aircraft and spacecraft are out of service due to necessary safety
inspections and repairs will have a considerable adverse impact on air
travel and other infrastructure elements such as satellite placement.
Therefore, EPA has preliminarily determined that requiring commercial
aviation and aerospace sectors to comply at this time with the ban on
methylene chloride use in paint and coating removal would cause
significant disruption to critical infrastructure. In addition, EPA has
preliminarily determined that compliance at this time with the proposed
ban on the manufacture, processing, and distribution in commerce of
methylene chloride for commercial paint and coating removal for these
specific commercial aviation and aerospace uses would also result in a
significant disruption to critical infrastructure. EPA's proposed
conditions for this exemption are described in this Unit, including
proposed requirements to comply with the WCPP.
    EPA acknowledges that in many cases commercial aviation facilities
may be more sophisticated and industrialized than other commercial
paint and coating removal operations. However, at the time of proposal,
data available to EPA demonstrate that the risks from paint and coating
removal in the aviation sector do not differ significantly from other
commercial paint and coating removal (Ref. 1). As shown in the 2020
Risk Evaluation for Methylene Chloride, high-end and central tendency
estimates for aircraft paint stripping are three orders of magnitude
below the benchmark for acute inhalation risks and four orders of
magnitude below the benchmark for chronic non-cancer inhalation risks
(Ref. 1). Even if use of APF 50 air supplied respirators were assumed,
the risks that remain for both high-end and central tendency would be
an order of magnitude below the benchmark for both endpoints (Ref. 1).
Therefore, while EPA expects that some of these facilities could
successfully follow the requirements of the WCPP, based on qualitative
information provided by stakeholders, this expectation is not
sufficiently supported by monitoring data in the 2020 Risk Evaluation
for Methylene Chloride. As a result, there is significant uncertainty
whether the requirements of the WCPP could be implemented successfully
in this sector for this particular use on a consistent and reliable
basis, in part due to the diversity of facilities in this sector. EPA
understands that generally large commercial aviation facilities could
have industrial hygiene expertise, sophisticated engineering and
administrative controls, and experience with rigorous safety
requirements and methods for ensuring continuous strong safety records
(Ref. 31). However, EPA is concerned about the ability of smaller
aircraft repair shops to implement the WCPP over the long term,
particularly for this condition of use. While EPA recognizes that the
proposed TSCA section 6(g) exemption for commercial aircraft paint and
coating removal could also cover these smaller aircraft repair shops,
the exemption is time-limited and ultimately would result in these
small shops using alternatives to methylene chloride. While Federal
agencies and contractors should be regulated under the WCPP, the Agency
is proposing that commercial use of methylene chloride for a similar
type of paint and coating removal be regulated with a time-limited,
conditional exemption under TSCA section 6(g), due to notable
differences in the two sectors. Specifically, exposure information
assessed by EPA resulted in key differences in risk estimates for paint
and coating removal by civilian aviation and DOD (see discussion in
this Unit and Unit V.A.1.). Additionally, as described in Unit V.A.1.,
Federal and Federal contractor facilities are subject to multiple
levels of oversight as a result of the governmental and public nature
of their activities, while many civilian aviation facilities are not
likely to experience the same level of scrutiny. EPA emphasizes that in
the absence of information, it must still ensure that unreasonable
risks are addressed. Because EPA has found inadequate information to
otherwise determine whether the unreasonable risk would be addressed
when using methylene chloride under a WCPP for commercial use of
methylene chloride for paint and coating removal from safety-critical,
corrosion-sensitive components of aircraft and aerospace vehicles for
commercial aviation and aerospace, EPA has determined that the proposed
exemption under TSCA section 6(g) allowing for time-limited,
conditional use of methylene chloride for this critical use is the
appropriate approach.
    EPA recognizes that in some situations, certain facilities may do
both Federal contractor and commercial aviation work and may use
methylene chloride for paint and coating removal from safety-critical,
corrosion-sensitive components on military, Federal, or commercial
aviation. EPA requests comment on whether such co-located activities in
a facility should be subject to the WCPP, rather than the exemption
under TSCA section 6(g). Additionally, EPA seeks additional information
and requests comment on whether it is possible to distinguish between
commercial aviation facilities that would be able to meet the WCPP and
those that would not, including what criteria should be used for such
distinctions (e.g., size of facility, volume

or type of work performed, record of exposure reduction practices). EPA
also requests comment on the extent to which specific commercial
aviation and aerospace uses or types of facilities could fully comply
with the WCPP to address identified unreasonable risk.
ii. Proposed Exemptions for Uses of Methylene Chloride for Paint and
Coating Removal That Are Essential for Critical Infrastructure
    For the reasons discussed in this Unit, EPA is proposing to provide
a 10-year exemption for commercial aviation and commercial aerospace
applications from the proposed prohibition on the use of methylene
chloride in commercial paint and coating removal. In defining the scope
of the exemption to limit the exemption to commercial aviation and
aerospace, EPA looked to the definitions and provisions of the Federal
Aviation Regulations in title 14 of the CFR. Air carriers and
commercial operators are certificated under 14 CFR part 119. Repair
stations are certificated under 14 CFR part 145. To effectively prevent
significant disruptions to critical infrastructure including commercial
aviation and aerospace, EPA would make this exemption available to
three different groups of commercial entities. In each case, the
exemption would be available only for the use of methylene chloride to
remove paint and coatings from safety-critical, corrosion-sensitive
components of aircraft or aerospace vehicles. The first group would
consist of those facilities that primarily maintain and repair aircraft
used by air carriers and commercial operators. More specifically,
maintenance and repair facilities operated by air carriers and
commercial operators certificated under 14 CFR part 119 would be
eligible for the exemption, as would be repair stations certificated
under 14 CFR part 145, if their primary business is performing
maintenance, preventive maintenance, rebuilding, or alteration of
aircraft operated by air carriers and commercial operators certificated
under 14 CFR part 119. The second group would consist of manufacturers
of aircraft intended for, or capable of being used by, air carriers and
commercial operators certificated under 14 CFR part 119. The third
group would consist of any person manufacturing or repairing
spacecraft, space vehicles, or payloads or similar hardware that is
intended for, or used in, commercial space transportation operations
subject to 14 CFR chapter III.
    The conditions for the proposed exemption would be: (1) The use of
methylene chloride for commercial paint or coating removal by
certificated air carriers, commercial operators, or repair stations, or
by manufacturers of aircraft or aerospace vehicles or hardware, would
be limited to the safety-critical, corrosion-sensitive components on
aircraft and aerospace vehicles; (2) The use of methylene chloride for
paint or coating removal would be required to be performed on the
premises of the certificated air carrier or commercial operator or
repair station, or of the manufacturer of aircraft or aerospace
vehicles or hardware; and (3) The certificated air carrier, commercial
operator, repair station, or manufacturer of aircraft or aerospace
vehicles and hardware manufacturer would have to comply with the WCPP
discussed in Unit IV.A.1.
    EPA wishes to make clear that the exemption for the commercial
aerospace and aviation industry would only be available for the purpose
of paint and coating removal from components of aircraft and spacecraft
that are corrosion-sensitive and safety critical components, such as
landing gear, gear boxes, turbine engine parts, and other aircraft and
spacecraft and components composed of metallic materials (specifically
high-strength steel, aluminum, titanium, and magnesium) and composite
materials. In addition, these components would have to be of the type
that not only require their paint or coatings to be removed for
inspection and maintenance but also would be so negatively affected by
the use of paint and coating removal chemicals or methods other than
methylene chloride that the safety of the system could be compromised.
General paint and coating removal on aircraft and spacecraft would not
be authorized under this exemption. One commenter on the 2017 proposal
suggested that EPA clarify that only the manufacturer of the component
may make this determination. In EPA's view, persons availing themselves
of the exemption would need to have a reasonable basis to conclude that
the components on which methylene chloride is used are corrosion-
sensitive and safety critical components within the meaning of the
definition. EPA believes such persons could rely, in part, on
information supplied by the manufacturer of the component. A
determination of whether a particular component of an aircraft or
spacecraft is a safety-critical corrosion-sensitive component would be
a fact-specific determination that takes into account the substrate and
character of the component, the effects of methylene chloride paint or
coating remover on the component, and other relevant factors.
    The entities subject to the proposed exemption would nonetheless
still be subject to the proposed general recordkeeping requirements
discussed in Unit IV.A., the WCPP recordkeeping requirements discussed
in Unit IV.A.1.f.iii., and requirements to maintain records that
demonstrate compliance with the exemption conditions, including the
condition that methylene chloride only be used for paint and coating
removal from corrosion-sensitive and safety critical components of an
aircraft or spacecraft. Pursuant to TSCA section 6(g)(3), if this
proposed exemption is finalized, EPA may by rule later extend, modify,
or eliminate the exemption, on the basis of reasonably available
information and after adequate public justification, if EPA determines
the exemption warrants a change. EPA would initiate this rulemaking
process (e.g., proposed rule, final rule) at the request of any
regulated entity benefiting from such an exemption, as appropriate. The
Agency is open to engagement throughout the duration of any TSCA
section 6(g) exemption, and emphasizes that to ensure continuity in the
event of an extension or modification request, such a request should
come at least 2 years prior to the expiration of an exemption.
    EPA requests comments on all aspects of the proposed TSCA section
6(g) exemption from the proposed prohibition on use of methylene
chloride in commercial paint and coating removal for paint and coating
removal essential for critical infrastructure by certificated
commercial air carriers, commercial operators, or repair stations, or
by manufacturers of aircraft or aerospace vehicles and hardware, noting
that the proposed exemptions would be limited to the safety-critical,
corrosion-sensitive components on aircraft and aerospace vehicles,
including safety-critical components.
b. Certain Emergency Uses of Methylene Chloride for Which No
Technically and Economically Feasible Safer Alternative Is Available
i. Analysis of the Need for TSCA Section 6(g)(2)(A) Exemption for NASA
Certain Uses in an Emergency
    EPA also considered a TSCA section 6(g) exemption for emergency use
of methylene chloride in the furtherance of NASA's mission. Under TSCA
section 6(g)(1)(A), EPA may ``grant an exemption from a requirement of
a . . . rule for a specific condition of use of a chemical substance or
mixture, if the Administrator finds that the specific condition of use
is a critical or essential use for which no technically and
economically feasible safer alternative is

available, taking into consideration hazard and exposure.'' For certain
specific conditions of use, EPA proposes that use of methylene chloride
by NASA and its contractors in an emergency be exempt from the
requirements of this rule because it is a critical or essential use
provided that (1) there is an emergency; and (2) NASA selected
methylene chloride because there are no technically or economically
feasible safer alternatives available during the emergency.
    NASA operates on the leading edge of science seeking innovative
solutions to future problems where even small volumes of an otherwise
prohibited chemical substance could be vital to crew safety and mission
success. During interagency review, NASA expressed concerns that there
will likely be circumstances where a specific, EPA-prohibited condition
of use may be identified by NASA during an emergency as being needed in
order to avoid or reduce situations of harm or immediate danger to
human health, or the environment, or avoid imperiling NASA space
missions. In such cases, it is possible that no technically and
economically feasible safer alternative would be available that meets
the stringent technical performance requirements necessary to remedy
harm or avert danger to human health, the environment, or avoid
imperiling NASA space missions.
    An emergency is a serious and sudden situation requiring immediate
action to remedy harm or avert danger to human health, the environment,
or to avoid imperiling NASA space missions. In NASA's case, there may
be instances where the emergency use of methylene chloride for specific
conditions of use is critical or essential to remedying harm or
averting danger to human health, the environment, or avoiding
imperiling NASA space missions. Because of the immediate and
unpredictable nature of emergencies described in this Unit and of the
less forgiving environments NASA operates in that offer little to no
margin for error, it is likely that, at the time of finalization of
this proposal, alternatives to emergency methylene chloride use may not
be available in a timely manner to avoid or reduce harm or immediate
danger (Ref. 39). In this way, these emergencies for particular
conditions of use meet the criteria for an exemption under TSCA section
6(g)(1)(A), because the emergency use of methylene chloride for listed
conditions of use is critical or essential and no technically and
economically feasible safer alternative will be available in a timely
manner, taking into consideration hazard and exposure.
    In support of the TSCA section 6(g)(1)(A) emergency use exemption,
NASA submitted detailed criteria which they must use to screen,
qualify, and implement materials to be used in spacecraft equipment, as
well as historical case studies that outline the loss of life and loss
of assets in the discharge of previous missions. In one of several
examples detailed, the Apollo I command module fire that claimed the
lives of three American astronauts demonstrated the need for careful
testing and continuity of materials (Ref. 39). Moreover, due to NASA's
rigorous safety testing requirements under various environmental
conditions, technically and economically feasible safer alternatives
may not be readily available during emergencies and may require certain
conditions of use of methylene chloride to alleviate the emergency.
    In another example, NASA identified a scenario concerning a mission
to the International Space Station (ISS) whereby, during a launch
evolution, the countdown was paused immediately prior to launch (T-2
minutes). NASA engineers identified a clogged filter and supply line as
the primary issue, which required immediate attention (i.e., line
flushing and filter cleaning). In this type of emergency scenario, an
already approved chemical substance rated for space system applications
is necessary to immediately remedy the situation. Although methylene
chloride was not used in this particular incident, if it were needed,
in the future to address such an emergency, then the proposed exemption
would allow for its lawful use--the countdown would resume and the
launch would occur. Conversely, without an exemption under the specific
condition of use (e.g., industrial and commercial use in non-aerosol
degreasers and cleaners), NASA's use of methylene chloride would be
otherwise prohibited, which would put NASA in an untenable position of
having to choose to either violate the law or place the mission (and
potentially the health and safety of its employees involved in the
mission) at risk.
    As described in Unit IV.A.5.a., the identification and
qualification of compatible materials in the context of aviation is
iterative and involves expansive collaboration between original
equipment manufacturers, Federal agencies, and qualifying institutions.
This is equally, if not more so, the case in the context of human space
flight operations undertaken by NASA (Ref. 39). NASA's mission
architecture requirements often are developed many years in advance of
an actual launch occurring. As part of mission planning, space systems
are designed, full scale mock-ups are built, and mission critical
hardware is constructed using materials qualified for spaceflight. Once
NASA's mission architecture requirements are developed, NASA may need
to retain emergency access to methylene chloride because its
alternatives may not have yet gone through NASA's rigorous
certification process before their use. Allowing NASA to retain
emergency use of methylene chloride would reduce the chances that this
rule will hinder future space missions for which mission architecture
infrastructure is being developed or is already built. While NASA
considers alternatives to the chemical substances it currently uses in
its space system designs, NASA has not yet identified technically and
economically feasible alternatives to proven chemistries in many
current applications. While EPA acknowledges that the use of methylene
chloride in emergency situations may be necessary in the near term, it
is also EPA's understanding that NASA will continue its work to
identify and qualify alternatives to methylene chloride. Thus, as with
the exemption described in Unit IV.A.5.a., EPA is proposing an
exemption duration of 10 years.
ii. Proposed Exemption for Use of Methylene Chloride for Emergency Uses
in the Context of Human Space Flight for Certain Uses
    For the reasons discussed in this Unit, EPA is proposing a 10-year
exemption for emergency use of methylene chloride in furtherance of
NASA's mission for the following specific conditions of use: Industrial
and commercial use as solvent for cold cleaning; Industrial and
commercial use as a solvent for aerosol spray degreaser/cleaner;
Industrial and commercial use in adhesives, sealants and caulks;
Industrial and commercial use in adhesive and caulk removers;
Industrial and commercial use in metal non-aerosol degreasers;
Industrial and commercial use in non-aerosol degreasers and cleaners;
and Industrial and commercial use as solvent that becomes part of a
formulation or mixture. EPA is also proposing to include additional
requirements as part of the exemption, pursuant to TSCA section
6(g)(4), including required notification and controls for exposure, to
the extent feasible: (1) NASA and its contractors must provide notice
to the EPA Administrator of each instance of emergency use within 15
days and; (2) NASA and its contractors would have to comply with the
WCPP described in Unit IV.A.1. to the extent feasible.

    EPA is proposing to require that NASA notify EPA within 15 days of
the emergency use. The notification would include a description of the
specific use of methylene chloride in the context of one of the
conditions of use for which this exemption is being proposed, an
explanation of why the use described qualifies as an emergency, and an
explanation with regard to the lack of availability of technically and
economically feasible alternatives.
    As with the exemption described in Unit IV.A.5.a., EPA expects NASA
and its contractors have the ability to implement a WCPP as described
in Unit IV.A.1. for the identified uses in the context of an emergency,
to some extent even if not to the full extent of WCPP implementation.
Therefore, EPA is proposing to require that during emergency use, NASA
must comply with the WCPP to the extent technically feasible in light
of the particular emergency.
    Under the proposed exemption, NASA and its contractors would still
be subject to the proposed general recordkeeping requirements discussed
in Unit IV.A.
    EPA requests comment on this TSCA section 6(g) exemption for
continued emergency use of methylene chloride in the furtherance of
NASA's mission as described in this Unit, and whether any additional
conditions of use should be included, in particular for any uses
qualified for space flight for which no technically or economically
feasible safer alternative is available. Additionally, EPA requests
comment on what would constitute sufficient justification of an
emergency.
c. Analysis of the Need for a TSCA Section 6(g) Exemption for
Commercial Furniture Refinishing
    While EPA in the past has proposed to exclude commercial furniture
refinishing from regulation of the use of methylene chloride in
commercial paint and coating removal, this proposed rule does not
exclude commercial furniture refinishing from the proposed prohibition
on the use of methylene chloride for commercial paint and coating
removal, because EPA has determined that this use drives the
unreasonable risk for methylene chloride, reasonably available
information demonstrates that alternative methods or substitute
chemicals are available to some extent, and, based on reasonably
available information, EPA has not found that a TSCA section 6(g)
exemption is warranted for the use of methylene chloride in commercial
furniture refinishing.
    The 2020 Risk Evaluation for Methylene Chloride identified risks
for commercial use of methylene chloride in paint and coating removal,
including furniture refinishing, as a result of acute and chronic non-
cancer exposures that would not be mitigated by an APF 50 respirator.
The 2020 Risk Evaluation for Methylene Chloride identified risks for
commercial use of methylene chloride in paint and coating removal,
including furniture refinishing, as a result of acute and chronic non-
cancer exposures that would not be mitigated by an APF 50 respirator.
EPA identified many alternative products for paint and coating
removers. However, some may require longer periods of time or rework of
equipment and processes in order to work for furniture refinishing
uses, or, though they may be used as paint and coating removers in
other contexts, may not be appropriate alternatives for use on wood
substrates. EPA's consideration of alternatives, including for safety
and flammability, is discussed further in Unit V.B., the Economic
Analysis, and Alternatives Assessment (Ref. 3, Ref. 40). Mechanical or
thermal methods (i.e., sanding, media blasting, or heat guns) are also
potential alternatives for this sector, though likewise they may damage
the substrate, require different processes, and often requires more
time (Refs. 33, 55, 66). While the economic impacts of prohibiting the
commercial use of methylene chloride for furniture refinishing may be
significant for this sector, it is unclear whether this will result in
firm closures, and, if so, how many. Given the magnitude of the risks
resulting from this use, including the documented fatalities (Ref. 32),
the likely inability of this sector to comply with a WCPP (as described
in Unit V.A.), and the availability of some alternatives, EPA
determined that a prohibition would be necessary the identified risks
that drive the unreasonable risk to health, as discussed in Unit V.A.1.
EPA requests comment on all aspects of this preliminary determination
that a TSCA section 6(g) exemption is not warranted for the use of
methylene chloride in furniture refinishing, including information on
the availability of alternatives and the time needed to implement
alternatives. EPA emphasizes that the Agency is seeking input regarding
whether an exemption is needed and welcomes information related to this
condition of use during the public comment period.

B. Primary Alternative Regulatory Action

    As indicated by TSCA section 6(c)(2)(A)(iv)(II) through (III), EPA
must consider the costs and benefits and the cost effectiveness of the
proposed regulatory action and one or more primary alternative
regulatory actions considered by the Agency. An overview of the
proposed regulatory action and alternative regulatory action for each
condition of use is in Unit IV.C.
    The primary alternative regulatory action described in this notice
combines prohibitions and requirements for a WCPP to address the
unreasonable risk from methylene chloride driven by the various
conditions of use, as well as time-limited exemptions under TSCA
section 6(g) for two uses. While in some ways it is similar to the
proposed regulatory action, the primary alternative regulatory action
described in this notice would allow a WCPP, including requirements to
meet an ECEL and EPA STEL, for several additional conditions of use
than would be allowed under the proposed regulatory action. The
alternative regulatory action additionally would include longer
compliance timeframes for prohibitions and a WCPP, as described in this
Unit.
    As in the proposed regulatory action described in Unit IV.A.1.,
EPA's primary alternative regulatory action described in this notice
would include WCPP, including requirements to meet an ECEL and EPA STEL
for: manufacturing: domestic manufacture; manufacturing: import;
processing: as a reactant; processing: incorporation into a
formulation, mixture, or reaction product; processing: repackaging;
processing: recycling; industrial and commercial use as a laboratory
chemical; and disposal.
    In addition, the primary alternative regulatory action described in
this notice would require a WCPP for additional industrial and
commercial conditions of use: industrial and commercial use in
finishing products for fabric, textiles, and leather; industrial and
commercial use as solvent that becomes part of a formulation or
mixture; industrial and commercial use as a processing aid; industrial
and commercial use for electrical equipment, appliance, and component
manufacturing; industrial and commercial use for plastic and rubber
products manufacturing; industrial and commercial use in cellulose
triacetate film production; industrial and commercial use for oil and
gas drilling, extraction, and support activities; and industrial and
commercial use in paint or coating removal from safety-critical,
corrosion-sensitive components of aircraft owned or operated by air
carriers or commercial operators certificated under 14 CFR part 119.

    EPA believes a WCPP may be a viable alternative to the proposed
prohibition for these additional industrial and commercial conditions
of use because, as discussed in Unit V.A., these conditions of use are
generally industrial in nature; owners or operators are likely
currently complying with the OSHA methylene chloride standard, so they
should be familiar with what is being required to meet the ECEL; and,
as far as the Agency is aware, these conditions of use have not
resulted in any documented fatalities. Because of the industrial nature
of the sectors relevant to these conditions of use, the owner or
operator may have the capability to successfully implement a WCPP to
ensure that the unreasonable risk, as a result of exposure to methylene
chloride, are prevented. However, at the time of proposal, EPA has not
yet received any monitoring data or detailed description of methylene
chloride involving activities for these conditions of use to confirm
that compliance with an ECEL of 2 ppm is possible. Therefore, concerns
about the feasibility of implementing an ECEL for these additional
industrial and commercial conditions of use, as discussed in Unit V.3.,
led EPA to propose that they be prohibited (see Unit IV.A.2.). EPA does
not have sufficient information to confidently conclude that facilities
engaged in these conditions of use could meet the ECEL for methylene
chloride.
    Therefore, EPA requests comment on the ways in which methylene
chloride may be used in the conditions of use that would be prohibited
(under the proposed regulatory action) due to concerns about
feasibility of implementing an ECEL, and the degree to which users of
methylene chloride in these sectors could successfully implement the
WCPP, including requirements to meet an ECEL and EPA STEL, described in
Unit IV.A.1. EPA is also requesting comment on whether to consider a
regulatory alternative that would subject more conditions of use to a
WCPP, instead of prohibition, than those currently contemplated in the
primary alternative regulatory action. EPA also requests monitoring
data and detailed descriptions of methylene chloride involving
activities for these conditions of use to determine whether these
additional conditions of use could comply with the WCPP such that risks
are no longer unreasonable.
    Specifically with regards to the condition of use ``Industrial and
commercial use as a processing aid,'' EPA notes that the description of
this condition of use (in Unit III.B.1.c.xxiii.) covers a broad range
of chemical use activities. During the SBAR Panel, one SER provided
process descriptions, diagrams, and monitoring data which indicated
that particular entity may already be able to meet an ECEL of 2 ppm.
This particular entity uses methylene chloride as a heat transfer fluid
in a closed system. Information provided to EPA indicated that
inhalation exposures were frequently below the ECEL and in some cases
below the level of detection, and while dermal exposure were possible,
they could be mitigated through use of PPE (Ref. 6). EPA's 2020 Risk
Evaluation for Methylene Chloride incorporated exposure estimates from
a different type of processing aid application that did not resemble
the SER's use, which is highly specialized and may be considered a sub-
use of the condition of use as a whole. EPA requests comment on the
degree to which other entities using methylene chloride as a processing
aid may otherwise comply with the proposed WCPP requirements for
methylene chloride. In the case that several entities are able to
demonstrate the continued use of methylene chloride without subjecting
workers to unreasonable risk is possible, through a combination of
monitoring data and process description, EPA acknowledges its
willingness to finalize a regulation under which this particular sub-
use of the condition of use, or the condition of use as a whole could
continue under the WCPP.
    Additionally, EPA notes that the alternatives analysis did not
specifically identify any alternatives for this condition of use (Ref.
40). This is a limitation of the type of analysis done, which was
specifically based on the use of alternative formulations currently on
the market, and therefore not applicable to most processing uses. EPA
emphasizes that this is not a positive finding that alternatives do not
exist for this condition of use. To that end, EPA requests comment on
the degree to which alternatives may or may not be available for use of
methylene chloride as a heat transfer fluid and in other processing aid
applications.
    In the event that EPA is not able to identify any alternatives for
this condition of use, and additional information is not provided that
would allow EPA to determine that the WCPP could address unreasonable
risk driven by this condition of use, EPA will consider finalizing a
prohibition that allows for an appropriate phaseout in accordance with
TSCA section 6(d). Alternatively, in the event that EPA is unable to
identify alternatives for this condition of use, and EPA determines
through new information provided that prohibition of the use would
significantly impact national security or critical infrastructure, EPA
will consider an exemption under TSCA section 6(g).
    Under the primary alternative regulatory action, EPA would prohibit
the manufacture, processing, and distribution in commerce of methylene
chloride for all consumer use. Additionally, under the primary
alternative regulatory action described in this notice and considered
by EPA, other than those conditions of use listed earlier for inclusion
under the WCPP, EPA would prohibit the remaining industrial and
commercial uses, including two uses for which EPA is proposing the WCPP
as the regulatory action: industrial or commercial use for paint and
coating removal from safety-critical, corrosion-sensitive components of
aircraft and spacecraft by Federal agencies and their contractors; and
industrial or commercial use as a bonding agent in the production of
specialty batteries for military or space applications by Federal
agencies and their contractors. Recordkeeping and downstream
notification would be required as described in Unit IV.A.4.
    For industrial or commercial use for paint and coating removal from
safety-critical, corrosion-sensitive components of aircraft and
spacecraft by Federal agencies and their contractors, and industrial or
commercial use as a bonding agent in the production of specialty
batteries for military or space applications by Federal agencies and
their contractors, the alternative regulatory action would include an
exemption from the prohibition for 10 years under TSCA section 6(g).
For the duration of this exemption, regulated entities would be
required to comply with the WCPP to the extent practicable.
    For these two uses, EPA has conducted an analysis of the
application of this rulemaking and found that a TSCA section 6(g)
exemption may be warranted if the primary alternative regulatory action
considered by EPA is adopted, in its entirety or in relevant part, in
the final rule. Based on discussions with and information provided by
industry stakeholders, EPA understands that these two uses of methylene
chloride by DoD, NASA, and other Federal agencies are essential for
national security and critical infrastructure.
    As discussed in greater detail in Unit V.B., EPA is aware that
there are specific military uses for which methylene chloride is
essential for paint and coating removal and for which there are no
suitable alternatives currently available. The military readiness of
DOD's warfighting capability is

paramount to ensuring national security, which includes ensuring the
maintenance and preservation of DOD's warfighting assets. DOD has
identified safety-critical uses of methylene chloride for ensuring
military aviation readiness. These consist of the use of methylene
chloride for the removal of coatings from safety-critical, corrosion-
sensitive military aviation components, such as landing gear, gear
boxes, and turbine engine parts, that not only require their coatings
be removed for inspection and maintenance but also would be so
negatively affected by the use of technically incompatible, substitute
paint removal chemicals or methods that the safe performance of the
aircraft could be compromised.
    EPA has evaluated the effect that a prohibition on methylene
chloride for industrial or commercial paint and coating removal could
have on military readiness and preliminarily determines that an
exemption would be warranted under TSCA section 6(g)(1)(B) to avoid the
significant deleterious impacts on national security that compliance
with the proposed prohibition could entail, should the primary
alternative regulatory action be adopted in the final rule in whole or
in part. More specifically, because the available alternatives either
cannot be used on certain substrates, such as high-strength steel or
magnesium, or take an unacceptably long time to work in certain
situations, compliance with the proposed prohibition would result in
important military assets being off-line for significantly longer
inspection and repair periods, which would significantly disrupt
national security.
    In addition, as noted by commenters on EPA's 2017 NPRM, there are
other Federal agencies that use safety-critical, corrosion-sensitive
components on aviation and space applications and stated that the
proposed exemption should also apply to those Federal agencies and
their contractors. These commenters asserted that, without an exemption
for NASA, the Department of Homeland Security (DHS), and the Federal
Aviation Administration (FAA), the proposed prohibition on the use of
methylene chloride for industrial or commercial paint and coating
removal could negatively affect national security and critical
infrastructure.
    EPA's analysis of the potential impacts on DOD's military readiness
and national security is equally applicable to NASA, DHS, and FAA. As
stated by commenters on EPA's 2017 NPRM (Ref. 46), aircraft and other
assets operated by DHS, NASA, and the FAA also contain safety-critical,
corrosion-sensitive components of the type described by DOD, and
suitable alternatives to methylene chloride are similarly not available
for all applications. Those agencies are also responsible for assets
that are essential to national security or constitute critical
infrastructure and contain safety-critical, corrosion-sensitive
components on which methylene chloride is used for paint and coating
removal. The Coast Guard, one of the five Armed Services of the United
States, is a military branch within DHS. Like the four Armed Services
within DOD, the Coast Guard is also responsible for warfighting assets
that may require the use of methylene chloride for the removal of
coatings from safety-critical, corrosion-sensitive components. The
Coast Guard's military readiness is as important as the military
readiness of the four Armed Services within DOD. Similarly, the
readiness of U.S. Customs and Border Protection aviation for monitoring
and protecting the borders of the United States is an integral part of
national security. As for NASA, the United States Space Priorities
Framework notes that space systems (e.g., flight components of
satellites and space craft) are part of the nation's critical
infrastructure and that the United States has significant national
security interests in space (Ref. 41). The integrity and performance of
our national airspace system, overseen by the FAA, is a matter of both
national security and critical infrastructure. FAA-operated aircraft
ensure the integrity of instrument approaches to airports and airway
procedures that constitute our National Airspace System infrastructure
(Ref. 42). The FAA's Flight Program Operations accomplishes this
through the airborne inspection of space- and ground-based instrument
flight procedures and the validation of electronic signals in space
transmitted from ground navigation systems, evaluating accuracy,
aeronautical data, human factors fly-ability, and obstacle clearance.
    As discussed in Unit V.B., substitute chemicals for paint and
coating removal for safety-critical, corrosion-sensitive components are
not technically feasible as they have one or more technical
limitations; are incompatible with underlying materials; and/or do not
support the coating removal requirements of safety inspections, non-
destructive inspection, material assessment, or field repair processes.
Therefore, EPA has preliminarily determined that DHS, NASA, and FAA
compliance with a prohibition on the use of methylene chloride for
industrial or commercial paint and coating removal, which would
preclude use of methylene chloride for removal of paint and coatings
from safety-critical, corrosion-sensitive components of these agencies'
aircraft and other assets, would significantly disrupt national
security and critical infrastructure in the same way that DOD's
compliance with a prohibition would. In addition, due to concerns about
impacts to the availability of methylene chloride for use in removing
paint and coatings from safety-critical, corrosion-sensitive
components, EPA has preliminarily determined that a ban on the
manufacture, processing, and distribution in commerce of methylene
chloride for industrial or commercial paint and coating removal for
these safety-critical, corrosion-sensitive components would also
significantly disrupt national security and critical infrastructure.
For this reason, if the primary alternative regulatory action
considered by EPA is adopted, in its entirety or in relevant part, in
the final rule, an exemption under TSCA section 6(g) would be warranted
to prevent significant disruption of national security and critical
infrastructure.
    EPA has also analyzed the need for a TSCA section 6(g) exemption
for use of methylene chloride as a bonding agent in the production of
specialty batteries for use in critical energy storage applications in
military and space exploration settings, including defense applications
such as precision guided weapons, military airframes, satellites, space
launch vehicles, and spacecraft. According to a maker of these
batteries, all major military and space applications, such as aircraft
(F-35, B2), radios, and Mars mission equipment, require these batteries
to function in very harsh conditions, including operation to -40 [deg]C
and storage at -54 [deg]C (Ref. 47). As discussed further in Unit V.B.,
EPA understands that methylene chloride is a superior bonding agent for
this process because of its unique evaporative qualities, and that
availability of technologically and economically feasible alternatives
to methylene chloride is lacking.
    As discussed in this Unit, EPA recognizes that military readiness
is paramount to ensuring national security, and that space systems are
part of our critical infrastructure and have impacts on national
security. Therefore, EPA has preliminarily determined that DOD and NASA
compliance with a prohibition on the use of methylene chloride as a
bonding agent in the production of specialty batteries for use in
critical energy storage applications in military and space exploration
settings would significantly disrupt national security and critical
infrastructure,

should the primary alternative regulatory action be adopted in the
final rule in whole or in part. In addition, due to concerns about
impacts to the availability of methylene chloride for use as a bonding
agent in the production of these specialty batteries, EPA has
preliminarily determined that a prohibition on the manufacture,
processing, and distribution in commerce of methylene chloride for use
as a bonding agent in the production of specialty batteries for use in
critical energy storage applications in military and space exploration
settings would also significantly disrupt national security and
critical infrastructure. For this reason, if the primary alternative
regulatory action considered by EPA is adopted, in its entirety or in
relevant part, in the final rule, an exemption under TSCA section 6(g)
would be warranted to prevent significant disruption of national
security and critical infrastructure.
    Given the potential severity of impacts from acute exposures, EPA's
proposed regulatory action would include relatively rapid compliance
timeframes. However, it is possible that longer timeframes would be
needed for entities to come into compliance; therefore, the primary
alternative regulatory action described in this notice would include
longer timeframes for implementation than the proposed regulatory
action. The prohibitions under the primary alternative regulatory
action would take effect in 360 days for manufacturers, 450 days for
processers, 540 days for distributing to retailers, 630 days for all
other distributors and retailers, and 720 days for industrial and
commercial users after publication of the final rule in the Federal
Register (in contrast to 90 days for manufacturers, 180 days for
processers, 270 days for distributing to retailers, 360 days for all
other distributors and retailers, and 450 days for industrial and
commercial users after publication of the final rule in the Federal
Register in the proposed action described in Unit IV.A.). Similarly,
the compliance timeframes for the WCPP under the primary alternative
regulatory action would be extended by 6 months in comparison to the
proposed action described in Unit IV.A: EPA would require that
regulated entities establish initial exposure monitoring according to
the process outlined in Unit IV.A. within 12 months, ensure that the
airborne concentration of methylene chloride does not exceed the ECEL
or EPA STEL within 15 months (and provide respiratory protection if
necessary), and implement an exposure control plan within 18 months.
EPA requests comment on the ability of regulated entities engaged in
the additional conditions of use that would be subject to a WCPP under
the primary alternative regulatory action to conduct initial monitoring
within 12 months, anticipated timelines for any procedural adjustments
needed to comply with the requirements, and the extent to which this
option could result in additional exposure, compared the proposed
regulatory option as described in Unit IV.A. Overall, EPA requests
comment on any advantages or drawbacks for the timelines outlined in
this Unit, compared to the timelines identified for the proposed
regulatory action in Unit IV.A.
    As noted earlier in this Unit, for some conditions of use, both the
proposed regulatory action and primary alternative regulatory action
would result in a prohibition. EPA emphasizes that for those conditions
of use, the primary alternative regulatory action includes a different
timeline for implementation of the prohibition, in comparison to the
proposed regulatory action. As discussed in more detail in Unit V.A.,
for those conditions of use, EPA also considered other regulatory
approaches available under TSCA section 6(a). However, EPA found that
none of these other regulatory approaches would address the
unreasonable risk.
    Where EPA has determined that a chemical substance presents
unreasonable risk under TSCA section 6(b)(4), EPA must undertake
rulemaking to ``apply one or more of the [TSCA Sec.  6(a)(1) through
(7)] requirements to such substance . . . to the extent necessary so
that the chemical substance . . . no longer presents such risk.'' TSCA
Sec.  6(a). ``In proposing and promulgating [such] a rule,'' EPA must
``consider and publish a statement based on reasonably available
information with respect to . . . the reasonably ascertainable economic
consequences of the rule, including consideration of . . . (II) the
costs and benefits of the proposed . . . regulatory action and of the
[one] or more primary alternative regulatory actions considered by
[EPA]; and (III) the cost effectiveness of the proposed regulatory
action and of the [one] or more primary alternative regulatory actions
considered by [EPA].'' EPA interprets this to mean that Congress
intended this ``primary alternative regulatory action'' to be another
regulatory option under TSCA Sec.  6(a)(1) through (7) that would meet
the requirements of TSCA Sec.  6(a), namely address the unreasonable
risk identified under TSCA section 6(b)(4) ``to the extent necessary so
that the chemical substance . . . no longer presents such risk.'' Here,
the proposed regulatory action is comprised of a mix of proposed
options under TSCA section 6(a), each directed at specific conditions
of use and with specified timeframes for compliance. The primary
alternative regulatory options considered by the Agency would adjust
the overall mix of TSCA section 6(a) requirements, including compliance
timeframes, resulting in a proposed regulatory action that is more
restrictive in some ways and less restrictive in others. For conditions
of use where the only options that would address the unreasonable risk
are prohibition options under TSCA Sec.  6(a)(2), the proposed option
and the primary alternative regulatory option are distinct because
implementing prohibitions on differing timetables under TSCA section
6(d) would result in a different mix of regulatory options with
different costs, benefits, and cost effectiveness than the proposed
regulatory action.

C. Overview of Conditions of Use and Proposed Regulatory Action and
Primary Alternative Regulatory Action

    The following Table 3 is a side-by-side depiction of the proposed
regulatory action with the primary alternative regulatory action for
each condition of use. Additionally, timeframes between the proposed
and primary alternative regulatory action differ as outlined in Units
IV.A. and B; those Units also contain additional details such as
exemptions proposed under TSCA section 6(g) and delayed compliance
dates under TSCA section 6(d) for specific applications.

     Table 3--EPA Proposed or Alternative Action by Condition of Use
------------------------------------------------------------------------
                                                   Action
                                  --------------------------------------
         Condition of use                                   Primary
                                        Proposed          alternative
                                    regulatory action        action
------------------------------------------------------------------------
Industrial and commercial use as   Prohibit..........  Prohibit.
 solvent for batch vapor
 degreasing.
Industrial and commercial use as   Prohibit..........  Prohibit.
 solvent for in-line vapor
 degreasing.
Industrial and commercial use as   Prohibit..........  Prohibit.
 solvent for cold cleaning.
Industrial and commercial use as   Prohibit..........  Prohibit.
 a solvent for aerosol spray
 degreaser/cleaner.
Industrial and commercial use in   Prohibit..........  Prohibit.
 adhesives, sealants and caulks.
Industrial and commercial use in   Prohibit..........  Prohibit.
 paints and coatings.
Industrial and commercial use in   Prohibit..........  Prohibit.
 paint and coating removers.
Industrial and commercial use in   WCPP..............  Prohibit, with a
 paint and coating removers from                        10-year time-
 safety critical, corrosion-                            limited
 sensitive components of aircraft                       exemption and
 and spacecraft owned or operated                       interim WCPP.
 by DOD, NASA, DHS, FAA.
Industrial and commercial use in   Prohibit, with a    WCPP.
 paint and coating removers from    10-year time-
 safety-critical, corrosion-        limited exemption
 sensitive components of aircraft   and interim WCPP.
 owned or operated by air
 carriers or commercial operators.
Industrial or commercial use as a  WCPP..............  Prohibit, with a
 bonding agent for acrylic and                          10-year time-
 polycarbonate in mission-                              limited
 critical military and space                            exemption and
 vehicle applications, including                        interim WCPP.
 in the production of specialty
 batteries for such applications.
Industrial and commercial use in   Prohibit..........  Prohibit.
 adhesive and caulk removers.
Industrial and commercial use in   Prohibit..........  Prohibit.
 metal aerosol degreasers.
Industrial and commercial use in   Prohibit..........  Prohibit.
 metal non-aerosol degreasers.
Industrial and commercial use in   Prohibit..........  WCPP.
 finishing products for fabric,
 textiles and leather.
Industrial and commercial use in   Prohibit..........  Prohibit.
 automotive care products
 (functional fluids for air
 conditioners).
Industrial and commercial use in   Prohibit..........  Prohibit.
 automotive care products
 (interior car care).
Industrial and commercial use in   Prohibit..........  Prohibit.
 automotive care products
 (degreasers).
Industrial and commercial use in   Prohibit..........  Prohibit.
 apparel and footwear care
 products.
Industrial and commercial use in   Prohibit..........  Prohibit.
 spot removers for apparel and
 textiles.
Industrial and commercial use in   Prohibit..........  Prohibit.
 liquid lubricants and greases.
Industrial and commercial use in   Prohibit..........  Prohibit.
 spray lubricants and greases.
Industrial and commercial use in   Prohibit..........  Prohibit.
 aerosol degreasers and cleaners.
Industrial and commercial use in   Prohibit..........  Prohibit.
 non-aerosol degreasers and
 cleaners.
Industrial and commercial use in   Prohibit..........  Prohibit.
 cold pipe insulations.
Industrial and commercial use as   Prohibit..........  WCPP.
 solvent that becomes part of a
 formulation or mixture.
Industrial and commercial use as   Prohibit..........  WCPP.
 a processing aid.
Industrial and commercial use as   Prohibit..........  Prohibit.
 a propellant and blowing agent.
Industrial and commercial use for  Prohibit..........  WCPP.
 electrical equipment, appliance,
 and component manufacturing.
Industrial and commercial use for  Prohibit..........  WCPP.
 plastic and rubber products
 manufacturing.
Industrial and commercial use in   Prohibit..........  WCPP.
 cellulose triacetate film
 production.
Industrial and commercial use as   Prohibit..........  Prohibit.
 anti-spatter welding aerosol.
Industrial and commercial use for  Prohibit..........  WCPP.
 oil and gas drilling,
 extraction, and support
 activities.
Industrial and commercial use in   Prohibit..........  Prohibit.
 toys, playground and sporting
 equipment.
Industrial and commercial use in   Prohibit..........  Prohibit.
 carbon remover, wood floor
 cleaner, and brush cleaner.
Industrial and commercial use in   Prohibit..........  Prohibit.
 lithographic printing plate
 cleaner.
Consumer use as solvent in         Prohibit\1\.......  Prohibit.\1\
 aerosol degreasers/cleaners.
Consumer use in adhesives and      Prohibit \1\......  Prohibit.\1\
 sealants.
Consumer use in brush cleaners     Prohibit \1\......  Prohibit.\1\
 for paints and coatings.
Consumer use in adhesive and       Prohibit \1\......  Prohibit.\1\
 caulk removers \1\.
Consumer use in metal degreasers.  Prohibit \1\......  Prohibit.\1\
Consumer use in automotive care    Prohibit \1\......  Prohibit.\1\
 products (functional fluids for
 air conditioners).
Consumer use in automotive care    Prohibit \1\......  Prohibit.\1\
 products (degreasers).
Consumer use in lubricants and     Prohibit \1\......  Prohibit.\1\
 greases.
Consumer use in cold pipe          Prohibit \1\......  Prohibit.\1\
 insulation.
Consumer use in arts, crafts, and  Prohibit \1\......  Prohibit.\1\
 hobby materials glue.
Consumer use in an anti-spatter    Prohibit \1\......  Prohibit.\1\
 welding aerosol.
Consumer use in carbon removers    Prohibit \1\......  Prohibit.\1\
 and other brush cleaners.
Manufacturing (Domestic            WCPP..............  WCPP.
 manufacturing).
Manufacturing (Import)...........  WCPP..............  WCPP.
Processing: processing as a        WCPP..............  WCPP.
 reactant.
Processing: incorporation into a   WCPP..............  WCPP.
 formulation, mixture, or
 reaction product.
Processing: repackaging..........  WCPP..............  WCPP.
Processing: recycling............  WCPP..............  WCPP.
Industrial and commercial use as   WCPP..............  WCPP.
 a laboratory chemical.
Disposal.........................  WCPP..............  WCPP.
------------------------------------------------------------------------
\1\ Prohibit manufacture, processing, and distribution in commerce for
  the consumer use.

V. Rationale for the Proposed Regulatory and Primary Alternative
Regulatory Actions

    This Unit describes how the considerations described in Unit
III.B.3. were applied when selecting among the TSCA section 6(a)
requirements to arrive at the proposed and primary alternative
regulatory actions described in Unit IV.A. and B.

A. Consideration of Risk Management Requirements Available Under TSCA
Section 6(a)

1. Workplace Chemical Protection Program (WCPP)
    One option EPA considered for occupational conditions of use was
establishing a WCPP, which would include an ECEL and related required
implementation measures, such as monitoring. As described in Unit
IV.A.1., the WCPP for methylene chloride would be non-prescriptive, in
the sense that owners and operators would not be required to use
specific equipment or engineering controls prescribed by EPA to achieve
the exposure concentration limit. Rather, a performance-based exposure
limit would enable owners and operators to determine how to most
effectively meet the exposure limits based on conditions at their
workplace, aligned with the hierarchy of controls. However, due to the
low exposure levels and stringent requirements in the WCPP necessary to
address the unreasonable risk from methylene chloride, EPA identified
only a relatively small number of conditions of use where the Agency
expects the WCPP can be successfully implemented.
    The central components of the WCPP are the ECEL and EPA STEL. EPA
has determined as a matter of risk management policy that ensuring
exposures remain at or below the ECEL and EPA STEL would eliminate any
unreasonable risk of injury to health driven by inhalation exposures
for occupational conditions of use subject to the WCPP.
    In the case of methylene chloride, EPA has calculated the ECEL for
methylene chloride to be 2 ppm (8 mg/m\3\) for inhalation exposures as
an 8-hour TWA in workplace settings, based on the chronic non-cancer
human equivalent concentration for liver toxicity from inhalation
exposures. This is the concentration at which an adult human, including
a member of a susceptible subpopulation, would be unlikely to suffer
adverse effects if exposed for a working lifetime (Ref. 11). EPA chose
the chronic non-cancer liver toxicity endpoint as the basis for this
exposure limit as it is the most sensitive of the endpoints identified,
and therefore will be protective of both acute and chronic cancer
inhalation endpoints over the course of a working day and lifetime.
    However, the well-established and severe acute hazard identified
for methylene chloride, from blurred vision to death, can be
experienced in much shorter timeframes. Therefore, EPA determined a
short-term exposure limit, or EPA STEL, of 16 ppm (57 mg/m\3\) as a 15-
minute TWA, based on the non-cancer endpoint of central nervous system
depression resulting from acute exposures, was necessary in order to
ensure the unreasonable risk was fully addressed in occupational
settings (Ref. 11).
    Once EPA identified the appropriate risk-based inhalation limits to
address identified unreasonable risk, EPA carefully considered the
appropriateness of such a program for each occupational condition of
use of methylene chloride, in the context of the unreasonable risk.
    Particular factors related to work activities that may make it
difficult for certain conditions of use to comply with an ECEL are
worth further discussion. One example includes work activities that may
take place in the field, such as on-site paint removal or the use of
adhesives in construction or renovation, making it challenging to
establish a regulated area and conduct monitoring. In other contexts,
the donning of air-supplied respirators would create challenges for
movement and feasibility of work activities that may take place in
small, enclosed spaces. Similarly, work activities that require a high
range of motion or for some other reason could create challenges for
the implementation of respiratory PPE are not good candidates for a
WCPP, such as use as an anti-spatter welding aerosol, where use of a
welding mask would impede the donning of an air-supplied respirator.
    EPA also considered the feasibility of exposure reduction
sufficient to address the unreasonable risk, even in facilities
currently complying with the OSHA methylene chloride standard. While
EPA acknowledges the regulated community's expected familiarity with
OSHA PELs generally, as well as facilities' past and ongoing actions to
implement the methylene chloride PEL and corresponding methods of
compliance in OSHA's methylene chloride standard, EPA's exposure limits
would be a full order of magnitude lower than the OSHA PEL. (The
differences between the ECEL and EPA STEL and the OSHA PEL are
discussed in more detail in Unit II.C.4.) This creates a significant
amount of uncertainty as to the ability of facilities engaging in most
industrial and commercial conditions of use to meet the ECEL and EPA
STEL (and associated action levels) without relying on the use of PPE
(or as discussed previously, if the nature of the activity precludes
use of PPE required to meet such a level), and, therefore, whether
exposures could be reduced in a manner aligned with the hierarchy of
controls, because under that hierarchy PPE is considered a measure of
last resort.
    EPA understands that this uncertainty extends to the applicability
of respirators as well. Although respirators, specifically SCBAs, could
reduce exposures to levels that are protective of non-cancer and cancer
risks, not all workers may be able to wear respirators. Individuals
with impaired lung function due to asthma, emphysema, or chronic
obstructive pulmonary disease, for example, may be physically unable to
wear a respirator. OSHA requires that a determination regarding the
ability to use a respirator be made by a physician or other licensed