recommended by NIOSH (NIOSH, 2001).  Data on exposure for sprayers found
fewer individuals receiving high exposures than at the facility
monitored in NIOSH (2000b), but 44% (15 of 34) of exposure samples were
higher than the proposed recommended WEL of 17 ppm, even after improving
ventilation.

	Modeled data of workplace exposure based on average amounts of spray
adhesive and average ventilation would result in exposure levels of
roughly 60 ppm, more than three times the WEL (ICF, 2006a).  In at least
four cases, workers using nPB-based adhesives have been exposed to
excessive amounts of nPB, to the point where they needed to be
hospitalized for adverse neurological effects (Ichihara et al., 2002 and
Miller, 2005; Raymond and Ford, 2005; Beck and Caravati, 2003, and
Majersik et al., 2004, 2005; Calhoun County, 2005).

	Considering the exposure data for nPB-based adhesives, we believe it is
unlikely that, even with ventilation, exposure levels for adhesives
users would be below the proposed recommended WEL on a consistent basis.
 Overall, 48% of all workers in these two facilities using nPB-based
adhesives were exposed to concentrations of nPB greater than the
proposed recommended WEL of 17 ppm (31 of 64 workers), even after
installing state-of-the-art ventilation with assistance from NIOSH.
Sprayers had significantly higher individual exposures than workers who
did not work directly with the nPB-based adhesive.

	Given the information above, we are concerned that nPB-based adhesives
cannot be reliably used in a manner that protects human health.  We
request comment and data on whether it is feasible to use nPB-based
adhesives with worker exposure levels consistently below the proposed
recommended WEL of 17 ppm on an 8-hr TWA.

	The available information indicates that all acceptable carrier
solvents in adhesives other than nPB have projected or actual exposure
less than the appropriate workplace exposure limit set by OSHA, the
ACGIH, the American Industrial Hygiene Association, or EPA.  Examples of
other carrier solvents currently used in adhesives and acceptable under
the SNAP Program include hydrocarbon solvents, acetone, methylene
chloride, and water.  EPA finds that there are other available
alternatives that present less risk to human health and the environment
compared to nPB in the adhesives end use.

	During the public comment period on the June 2003 NPRM, one commenter
representing the adhesives industry stated that there are some small but
critical applications that require nonflammability and high solvency
(Collatz, 2003).  The commenter did not specify what those applications
are, and whether there was information showing that other types of
adhesives, such as those using water, flammable solvents, or methylene
chloride, are technically infeasible in these applications.  We request
comment and data on whether there are any unique applications of nPB in
the adhesives end use for which there are no other technically feasible
alternatives, and thus, for which nPB should be allowed.  If so, we
would consider finding nPB acceptable subject to narrowed use limits,
with requirements for each end user to perform a demonstration that
there are no other technically feasible alternatives for their
particular site, to install local exhaust ventilation equipment designed
to reduce exposure levels to the proposed recommended WEL, and to
perform worker exposure monitoring.  Alternatively, if there were
sufficient information provided during the public comment period showing
that there are applications in which only nPB can be used, we would
consider finding nPB acceptable in adhesives, subject to use conditions
requiring installation of local exhaust ventilation and worker exposure
monitoring, and subject to a narrowed use limit for those specific
applications where other alternatives are not technically feasible,
without requiring a site-specific demonstration that nPB is the only
feasible alternative.  This would allow for safer use of nPB in any
applications where nPB is the only alternative, if any such applications
exist.

	D.	Coatings  tc "		4.	Coatings " \l 3

	We are proposing to find nPB acceptable, subject to use conditions, for
facilities that have provided EPA information demonstrating their
ability to meet the recommended workplace exposure limit as of [INSERT
DATE OF PUBLICATION].  The SNAP submission with information on coatings
was made for a single facility and EPA is unaware of anyone else
interested in using nPB in this end use.  Workplace exposure levels to
nPB from ammunition sealant at Lake City Army Ammunition Plant ranged
from less than 1 ppm up to 21 ppm on an eight-hour time-weighted
average.  Thirty-four of 35 samples had concentrations below 10 ppm, and
the mean concentration for the plant was less than 4 ppm (Lake City Army
Ammunition Plant, 2004).  The vast majority of measurements show worker
exposure well below EPA’s proposed recommended workplace exposure
limit of 17 ppm.  Thus, we believe that nPB can be used as safely as
other acceptable solvents used at their workplace exposure limits under
the conditions at this facility.

	Other acceptable substitutes for ozone-depleting substances in
coatings, in general, include oxygenated solvents, hydrocarbon solvents,
terpenes, hydrofluoroethers 7100 and 7200, benzotrifluorides (include
parachlorobenzotrifluoride), monochlorotoluenes,
trans-1,2-dichloroethylene, chlorinated solvents, water-based
formulations, and high-solids formulations.  In the particular
application for ammunition coatings, the submitter evaluated a large
number of alternatives and found that n-propyl bromide was the only one
of 29 solvents tested that could meet performance specifications at this
facility (Harper, 2005).  Thus, it is not clear that there are other
available substitutes available for this specific application, and
exposure data show that in this specific application, nPB can be used in
a way that does not significantly increase risks to human health
compared to other acceptable substitutes in the coatings end use.

VII.   How did EPA choose the use conditions in the alternate proposal,
and why?

	We also take comment on an alternate proposal.  In order to provide
flexibility for companies to choose nPB, but only where it would not
pose a significantly greater risk than use of other available
alternatives, we could require users to meet use conditions specifying a
worker exposure limit, monitoring, and recordkeeping.  Users would be
required to (1) meet a workplace exposure limit of 17 ppm on an
eight-hour time-weighted average, (2) monitor workers’ exposure to nPB
using a personal breathing zone sampler on an eight-hour time-weighted
average initially and periodically (every 6 months or longer, depending
on the concentration during initial monitoring), and (3) keep records of
the worker exposure data on site at the facility for at least three
years from the date of the measurement.  The use condition requiring
users to meet the WEL would protect human health by ensuring that
exposure is not above a level that is safe.  Monitoring of worker
exposure levels would give users a tool to identify and correct faulty
work practices or improve or replace equipment that provides
insufficient ventilation that, if undetected and uncorrected, would
result in exposure to nPB above the WEL of 17 ppm.  Keeping records of
the monitoring data would give EPA the ability to enforce the monitoring
and exposure limit requirements.

In developing this proposal, EPA considered whether nPB presented a more
significant risk than other available ODS alternatives.  We believe that
use of nPB does not present significantly more risk so long as exposure
levels are maintained below the proposed WEL.  Establishing use
conditions could help ensure that users meet the WEL.  Therefore, EPA is
taking comment on use conditions that would require users to meet the
workplace exposure limit and monitor worker exposure.

A.   Use Conditions and Their Rationale

	The major provisions of the use conditions and the related issues that
EPA considered in developing the alternate proposal are as follows:

Workplace exposure limit.   A requirement to meet the workplace exposure
limit would be an interim measure to ensure that nPB will be used safely
until OSHA issues a final permissible exposure limit (PEL) under the
Occupational Safety and Health Act.  In the event that OSHA issues a
final PEL, it would supersede EPA’s WEL.  EPA is specifically
deferring to OSHA, and has no intention to assume responsibility to
displace OSHA’s authority under Public Law 91-596.  EPA’s WEL would
not pre-empt the authority of OSHA to take regulatory or enforcement
action with respect to exposure to this substance.  This is made clear
by the Clean Air Act under which EPA would promulgate this regulation
(Subchapter VI – Stratospheric Ozone Protection), which provides at 42
U.S.C. 7610 in pertinent part: “…this chapter [Chapter 85 – Air
Pollution Prevention] shall not be construed as superseding or limiting
the authorities, under any other provision of law, of the Administrator
or any other Federal officer, department, or agency.”  By issuing a
WEL for nPB, EPA’s intention would be to fill existing regulatory gaps
during the interim period of substitution away from ozone-depleting
compounds and provide the needed margin of protection for human health
and the environment until OSHA develops other regulatory controls or
standards under appropriate authorities.

Worker exposure monitoring.  We modeled the worker exposure monitoring
requirements on OSHA’s requirements for monitoring for methylene
chloride. 29 CFR 1910.1052(d).  We expect that the regulated community
would be familiar with this approach and there might be fewer changes
for regulated businesses if OSHA later were to establish a workplace
standard for nPB.  Because the WEL is an 8-hr TWA value that is derived
from studies that measured exposure via inhalation, the proposed use
conditions require the owner or operator to monitor 8-hr TWA values that
measure workers’ exposure in the breathing zone (e.g., samples from a
worker’s collar).  We are not proposing to monitor short-term
exposures because acute, short-term exposures of nPB are not of
significant health concern, so long as long-term exposures are below the
8-hour TWA limit (ERG, 2004).

	Option for monitoring representative set of workers.  Personal breath
zone samples could be taken either from each worker using nPB or from a
representative set of exposed workers expected to have the highest
exposure.  Allowing exposure monitoring from representative workers
using nPB, rather than requiring separate monitoring for each individual
using nPB, would reduce overall compliance burden, while still detecting
any exposure levels in excess of the WEL and avoiding underestimates of
exposure.

	Initial monitoring.  Users already using nPB would need to undergo
exposure monitoring no later than 90 days after the date the final rule
becomes effective.  A user that has never used nPB before would need to
perform initial monitoring before beginning to use nPB in the
facility’s industrial applications.

	Periodic monitoring.	Monitoring would have to be performed periodically
on a schedule based on the results of the most recent set of exposure
monitoring data.  Monitoring from workers’ personal breathing zone
would be required during the next six months if an initial measurement
finds exposure levels between the action level and the 8-hour TWA
exposure limit.  No periodic monitoring would be required if initial
measurements are below the action level.  We would use a value of 8.5
ppm, half the proposed WEL of 17 ppm, as the action level.  OSHA
standards also set an action level of half the PEL.

	Monitoring would no longer be required where the most recent exposure
monitoring data found all worker exposures at or below 8.5 ppm.  OSHA
rules also reduce monitoring requirements for exposures below the action
level because if measured values are that low, it is unlikely that any
measurement will exceed the PEL unless a major change to the process
occurs.

	Monitoring for changes in workplace conditions or nPB use.  New
monitoring would be required if an event occurs that would make the most
recent set of monitoring data no longer representative.  Examples of
these changes are discussed above in section III.F.  Normally, EPA would
expect that the owner or operator would plan new applications of nPB or
changes to control equipment or work practices and would perform a test
for worker exposure levels before using nPB on a regular basis in that
application.  In the case of an emergency, such as a breakdown of
ventilation equipment or a leak, we would expect exposure monitoring to
be performed as soon as possible, and no later than 7 days after the
change in workplace conditions.   This period is intended to give an
owner or operator time to locate and purchase exposure monitoring
equipment in an emergency where the equipment may not already be
available at the facility.

Monitoring method and accuracy.  We take comment on the use of NIOSH
methods 1003 and 1025 (NIOSH, 2003b and c) for analyzing nPB exposure
under the alternate proposal.  Several of the studies that supplied EPA
with exposure data used this method and they are standardized methods
prepared by NIOSH, a recognized authority on industrial hygiene.  In
addition, we would allow other methods that are accurate to + 25% at the
95 percent confidence level.  Based on the accuracy of available
methods, most OSHA standards require exposure monitoring accurate to 25%
at the 95 percent confidence level, as in the methylene chloride
standard (29 CFR 1910.1052(d)(1)(iii)(A)) and other OSHA standards.

Recordkeeping requirements.  We would require that users keep records of
the worker exposure data for up to three years from the date the
measurement is taken. This would provide information allowing EPA to
determine if facilities are complying with the WEL and if people exposed
to nPB are sufficiently protected.  However, we note that OSHA’s
standard on access to employee exposure and medical records requires
retaining exposure records for at least 30 years (29 CFR
1910.1020(d)(ii)), and these requirements would still be in effect.

Responsibility for meeting requirements.  Under the alternate proposal,
the owner or operator of a facility using nPB would be responsible for
meeting the rule’s use conditions.

B.	Advantages and disadvantages of the alternate proposal

Setting use conditions that require users to meet a WEL and to monitor
and keep records to demonstrate achieving the WEL would protect the
health of nPB users while giving industry more flexibility and more
options for ODS substitutes, compared to finding nPB unacceptable.  This
could be especially useful for users of HCFC-141b as an aerosol solvent
who are seeking an effective ODS substitute.  If there were any
situations in which other available alternatives did not provide as good
performance, nPB would still be available as an option, provided the use
conditions could be met.  The monitoring requirements would encourage
good industrial hygiene and safe use of nPB.

Considering the list of use conditions above, we believe that setting
use conditions requiring a WEL, worker exposure monitoring, and
recordkeeping would be complex and potentially confusing.  Requiring
users to meet the WEL, although providing greater potential flexibility,
also would provide less certainty about how to comply.  A user could
spend considerable time and expense trying to meet the WEL, only to find
that it is not achievable.

In the past, EPA only required a WEL for solvents that were new for
which there was limited workplace experience and a concern that the
exposure limit might be exceeded, such as when HFC-4310mee,
HCFC-225ca/cb, monochlorotoluenes, and benzotrifluorides were first
introduced.  Since then, we have concluded that users would easily be
able to meet exposure limits for most substitutes for which such a limit
existed, and thus, EPA found no need to impose a workplace exposure
limit as a use condition.  For a compound such as nPB, for which
workplace exposure data exist, there is greater certainty as to whether
the WEL would be exceeded.  Given the limited circumstances under which
we expect aerosol and adhesive users could meet the workplace exposure
limit and given the availability of other, less toxic alternatives in
both of these end uses, EPA would prefer to find nPB unacceptable in
aerosols and adhesives.   Further, considering that so many users of nPB
for metals, electronics, and precision cleaning and the users of nPB at
the Lake City Army Ammunition Plant meet the proposed WEL without
regulatory requirements (US EPA 2003; Lake City Army Ammunition Plant,
2004), it appears unnecessary to require an exposure limit in those end
uses.

What other options did EPA consider?

EPA considered several different options in preparing this proposed
rule, but we prefer the approach proposed in this rule.  We also take
comment on the options discussed below.

A.	Regulatory options based on the ACGIH’s Threshold Limit Value

	We considered using ACGIH’s TLV of 10 ppm as a workplace exposure
limit to recommend and to use in assessing human health risks to
workers.  For certain other compounds that EPA found acceptable, we used
a TLV when available (e.g., acetone, cyclohexane, isopropyl alcohol).
However, as discussed above in section V.A, EPA has concerns about the
documentation and basis of ACGIH’s TLV derivation for nPB.  We note
that if we were to choose the TLV as the appropriate workplace exposure
limit for assessing human health risks of nPB, we would have proposed
the same decisions for each end use for the following reasons.

	We believe that workers using nPB in solvent cleaning usually will not
be exposed in excess of the ACGIH’s TLV of 10 ppm because roughly 70%
of samples from the workplace already meet this level, even when users
were aiming to meet a higher exposure limit of 25 ppm (US EPA, 2003).
Further, information from an nPB solvent supplier with a product
stewardship program demonstrates that users could take steps that
effectively reduce emissions further (Kassem, 2003).

	For aerosol solvents, as mentioned above in Section VI.B, it would be
difficult for users in this end use to meet a higher recommended WEL of
17 ppm.  Considering available exposure data from personal samples in
two studies, only one of seven samples on an eight-hour time-weighted
average showed an exposure level of 10 ppm or lower (ICF, 2006a).
Modeled exposures exceeded 10 ppm, even with some ventilation, if more
than a pound of nPB were used in a day.

	In the adhesives end use, 80% of the exposure data are above 10 ppm,
even after installing state-of-the-art ventilation.  Only one sprayer
was exposed to 10 ppm or less in reports from NIOSH (NIOSH, 1999, 2000a,
2002a, 2002b, 2003, etc).  Modeled data of workplace exposure based on
average amounts of spray adhesive and average ventilation would result
in exposure levels of roughly 60 ppm, approximately six times more than
a level of 10 ppm (ICF, 2006a).

	Tests at the Lake City Army Ammunition Plant showed an ability to meet
a WEL of 10 ppm, with the vast majority of measurements below that
value.  Thirty-four of 35 samples had concentrations below 10 ppm, and
the mean concentration for the plant was less than 4 ppm (Lake City Army
Ammunition Plant, 2004).

Regulatory options requiring ventilation equipment

	We considered use conditions for the adhesive and aerosol solvent end
uses that would reduce the human health risks of using nPB by reducing
exposure levels with requirements for installation and use of
ventilation equipment.

Aerosols

	For the aerosol solvent end use, EPA considered proposing a requirement
for installation of ventilation equipment.  Such a use condition would
need to specify and define which kinds of ventilation equipment would be
necessary.  For example, because one study on exposure levels found that
exposure fell below 17 ppm reliably only where both local exhaust
ventilation and regional ventilation equipment were used, a possible
requirement would be for installation of both local exhaust ventilation
and regional ventilation.  Local exhaust ventilation is ventilation that
removes vapors from a specific work location using ducts and fans.
Regional ventilation is ventilation that moves air around in a large
working area, such as one or more fans used for an entire room.  A
problem with requiring the type of ventilation equipment that all
facilities must use is that it still might not provide enough
ventilation in some situations and in other situations may be
unnecessary to meet the WEL.

	Another approach for aerosols we considered was to require a specific
level of ventilation.  Possible criteria for the level of ventilation
would be the air flow rate, in cubic feet per minute (cfm) or cubic
meters per second, or the face velocity at the location where a user
would work, in feet per minute (fpm) or meters per second face velocity.
 Based on both modeling and exposure data from one study (ICF, 2006a;
Linnel, 2003), an appropriate air flow rate for nPB-based aerosols would
be greater than 1900 cfm and an appropriate face velocity would be 170
fpm.  Alternatively, we considered requiring that facilities meet the
guidelines for face velocity in spray booths from the ACGIH Ventilation
Manual, in the range of 100 to 150 fpm, depending on the specific type
of booth.

	These options would appear to provide greater flexibility for industry
compared to finding nPB unacceptable in aerosol solvents.  However, our
understanding is that in most aerosol applications, it might not be
feasible to install adequate ventilation, and thus, to reduce human
health risks.  In the case of benchtop cleaning or degreasing, such as
during rework of individual parts that are not yet sufficiently clean,
it is possible to transport the part to a hood or spray booth to provide
sufficient ventilation.  However, for applications that require in-place
cleaning such as cleaning energized electrical contacts and switches,
maintenance in underground mines, or cleaning hot elevator motors, it is
not feasible to install ventilation equipment in place or to remove the
parts for cleaning in ventilation equipment (CSMA, 1999; Linnell, 2003).
 Information available to EPA shows that benchtop cleaning is perhaps
25% or less of the market for the ODS being replaced in aerosols (ICF,
2004) and that electrical contact cleaning makes up the vast majority of
the market for nPB-based aerosols (Williams, 2005); thus, we expect that
necessary ventilation cannot be installed in most aerosol applications
for nPB.  It would be difficult to explain and potentially confusing for
users that an aerosol product may be used for cleaning in one location
in a facility, but not in another, particularly when the ODS being
substituted for could be used in all locations without excessive worker
exposure.   Further, it would be difficult for EPA to enforce use
conditions on ventilation equipment, because aerosols are portable and
can easily be used outside of the ventilation equipment.  Other
acceptable substitutes, such as blends of HFEs or HFCs and
trans-dichloroethylene, are available in these end uses.

Adhesives

EPA also considered use conditions for ventilation equipment or for
specific ventilation levels for use of nPB-based adhesives.  However, to
date, we have found no study that demonstrates a ventilation option that
could achieve a WEL of 17 ppm when using spray adhesives.  Even with
state-of-the-art ventilation equipment installed with the expert
assistance of NIOSH, adhesives users were not able to lower exposure
limits sufficient to protect the vast majority of their workers.
Modeling of different levels of adhesive usage and ventilation, based on
conditions at different facilities indicates that air flow rates would
need to be more than 100,000 cfm.  Even this high air flow rate might
not be sufficient, since an air flow rate of 28,500 cfm resulted in
exposure levels of 3.5 to 35 times the WEL, depending on the amount of
adhesive used (ICF, 2006a, Att. D).  Less toxic substitutes such as
water-based adhesives and acetone-based adhesives are available in this
end use.

IX. 	What are the anticipated costs of this regulation to the regulated
community? tc "What are the anticipated costs of this regulation to the
regulated community?"

	As part of our rulemaking process, EPA estimated potential economic
impacts of this proposed regulation.  In our analysis, we assumed that
capital costs are annualized over 15 years or less using a discount rate
for determining net present value of 7.0%.  The acceptability
determination for solvents cleaning imposes no requirements and thus
creates no additional cost to users.  In addition, because the use
condition for coatings still permits nPB’s use in the only known
coatings application using nPB, we find no additional cost to the user
community from this regulatory provision.  We found that if this
proposed rule were to become final, the cost to the user community of
the unacceptability determinations, which are regulatory prohibitions on
the use of nPB in adhesives and aerosols, would be in the range of $2.3
to $6.7 million per year for adhesive users and $ 36.3 to 39.7 million
per year for aerosol users.

	EPA also considered potential costs end users could incur if they
implemented the recommended acceptable exposure limit and are not
already achieving it.  EPA found that those users using nPB-based
solvents in a vapor degreaser would save money by reducing solvent
losses, and that the savings would recover the costs of emissions
controls (e.g., secondary cooling coils, automated lifts or hoists)
within a year of installation.  Based on evidence from solvent
suppliers, EPA believes that some of those users would have chosen to
use nPB in order to avoid meeting requirements of the national emission
standard for halogenated solvents cleaning and that they would only
become aware of the potential savings due to reduced solvent usage as a
result of this proposal (Ultronix, 2001; Kassem, 2003; Tattersall,
2004).  Based on available exposure data for each sector, we assumed
that 80% of nPB users in the non-aerosol solvent cleaning sector already
achieve exposure levels of 17 ppm or less (US EPA, 2003).  Of those nPB
solvent users with exposure levels above 17 ppm, we examined the cost
associated with reducing emissions on average by 60%.

Full implementation of the recommended workplace exposure guideline
across all nPB users in solvent cleaning would save up to $2 million
dollars per year.  The value will depend on the number of users that
attempt to meet the recommended exposure guideline, the number already
achieving the WEL with existing equipment, the initial exposure level of
cleaning solvent users, the price of nPB, and the amount of emission
control equipment installed.

When the potential costs of compliance with the regulatory requirements
and the recommended workplace exposure limit are considered together,
EPA estimated the total cost in all sectors would range from $ 37.0 to
44.4 million annually.

	We also estimated the cost to the user community of the use conditions
in the alternate proposal for aerosols, adhesives, coatings, and solvent
cleaning.  The requirements for users to meet a workplace exposure limit
and to perform exposure monitoring would be in the range of $ 41.5 to
72.2 million per year.  The upper end of the range of estimated impacts
likely assumes laboratory grade ventilation for aerosols, which we
expect to be significantly more expensive than standard industrial fume
hoods or spray booths (approximately $10,000 compared to $1,000 for each
hood).  For coatings, use of nPB is limited to a single facility that
already performs workplace exposure monitoring.  For aerosols and
adhesives, we assumed the installation of fume hoods or spray booths,
the use of personal protective equipment, and monitoring for 1.9 to 2.0
times per year.  For solvent cleaning, we assumed no change in equipment
for 80% of users, the upgrading of vapor degreasing equipment for the
remaining 20%, and monitoring an average of 1.3 times per year.  Using
these assumptions, we calculated the cost of the use conditions in the
alternate proposal at $18.0 to 24.0 million for adhesive users, $24.3 to
43.5 million for aerosol users, and $ -0.8 to $ 4.7 million for solvent
cleaning users.  The estimated cost of the use conditions does not
consider that some users could choose to switch to other alternatives at
a lower cost.

	Estimated costs of the proposed regulation and alternate proposal are
summarized in Table 14.  For more detailed information, see section
XIII.C. below and EPA’s analysis in the docket (US EPA, 2006).

Table 14.  Estimated Costs of Regulatory Options EPA is Providing for
Comment

Sector or End Use	Requirements under Alternate Proposal	Annual Cost of
Alternate Proposal	Requirements under Proposed Rule	Annual Cost of
Proposed Rule

Solvent Cleaning (Metals, Electronics, and Precision Cleaning)	Achieve
WEL of 17 ppm; exposure monitoring, one or two times per year;
recordkeeping 	$-0.8 to 4.7 million	None explicit; recommended WEL of 17
ppm with expectation that users will meet WEL	Cost savings of up to $
2.0 million from reduced solvent consumption when meeting WEL

Aerosol Solvents	Achieve WEL of 17 ppm; exposure monitoring one or two
times per year; Recordkeeping	$24.3 to 43.5 million	Cease use of nPB and
switch to a different ODS substitute.	$ 36.3 to 39.7 million

Coatings	Achieve WEL of 17 ppm; exposure monitoring, one or  two times
per year; recordkeeping. 	None; only known facility using nPB-based
coatings already achieves the WEL and performs exposure monitoring	None
explicit; recommended WEL of 17 ppm with expectation that users will
meet WEL. Decision only applies to use nPB in coatings at at facilities
that have provided EPA information demonstrating their ability to meet
the recommended workplace exposure limit as of [INSERT DATE OF
PUBLICATION].	None; only known facility using nPB-based coatings already
achieves the WEL

Adhesives	Achieve WEL of 17 ppm; exposure monitoring, one or two times
per year; recordkeeping	$ 18.0 to 24.0 million	Cease use of nPB and
switch to a different ODS substitute.	$ 2.3 to 6.7 million

Total

$ 41.5 to 72.2 million

$37.0 to 44.4 million

X.	Comparison of EPA’s June 2003 proposal and this proposal tc "VII.
Comparison of EPA’s June 2003 proposal and today’s proposal"

	Table 15 compares the acceptability determination and evidence cited in
the June 2003 proposal and this proposal.

Table   SEQ Table \* ARABIC  1 5: n-Propyl Bromide Acceptability
Decision

Proposed Decision	2003 Proposed Rule	Current Proposed Rule—Preferred
Proposal

Industrial End Uses #1-3:

Metals Cleaning, Electronics Cleaning, and Precision Cleaning (Solvent
Cleaning)	Acceptable, Subject to a Use Condition (Limiting use to nPB
formulations containing no more than 0.05% by weight isopropyl bromide);
WEL of 25 ppm1 on 8-hr TWA recommended	Acceptable; WEL of 17 ppm2 on
8-hr TWA recommended

Industrial End Use #4:

Aerosol Solvents	Acceptable, Subject to a Use Condition (Limiting use to
nPB formulations containing no more than 0.05% by weight isopropyl
bromide; WEL of 25 ppm1 on 8-hr TWA recommended	Unacceptable

Industrial End Use #5:

Adhesives	Acceptable, Subject to a Use Condition  (Limiting use to nPB
formulations containing no more than 0.05% by weight isopropyl bromide;
WEL of 25 ppm1 on 8-hr TWA recommended	Unacceptable

Industrial End Use #6: Coatings	Not addressed	Acceptable, Subject to
Narrowed Use Limits (Decision limited to  coatings at facilities that
have provided EPA information demonstrating their ability to meet the
recommended workplace exposure limit as of [INSERT DATE OF PUBLICATION);
WEL of 17 ppm2 on 8-hr TWA recommended

1 Proposed Workplace Exposure Limit of 25 ppm based upon nPB’s effect
on sperm motility from ICF’s evaluation of the WIL 2001 Study “An
Inhalation Two-Generation Reproductive Toxicity Study of 1-Bromopropane
in Rats.”

ICF, 2001. ‘‘Brief Discussion of the BMD Approach: Overview of its
Purpose, Methods, Advantages, and Disadvantages.’’ Prepared for U.S.
EPA.

ICF, 2002a. ‘‘Risk Screen for Use of N Propyl Bromide.’’
Prepared for U.S. EPA, May, 2002.

ICF, 2002b. Comments on the NTP- Center for the Evaluation of Risks to
Human Reproduction, Final Report on 1- Bromopropane.  Cover Letter Dated
5/9/02.

Also, evaluation of documents by CERHR (2002a, b), Doull and Rozman
(2001), Rodricks (2002), Rozman and Doull (2002), SLR International
(2001), and others.

2 Proposed Workplace Exposure Limit of 17 ppm based upon nPB’s effect
on the number of estrous cycles and estrous cycle length from ICF’s
re-evaluation of the WIL 2001 Study “An Inhalation Two-Generation
Reproductive Toxicity Study of 1-Bromopropane in Rats.”

ICF, 2006a, “Risk Screen for Use of N Propyl Bromide”, Prepared for
U.S. EPA, April, 2006.

ICF, 2004c, “Expert Panel Response on nPB AEL”, Prepared for U.S.
EPA, December, 2004

ICF, 2004d, “nPB Human Relevance”, Prepared for U.S. EPA, September,
2004

Also, evaluation of documents by Stelljes and Wood (2004); TERA (2004);
ACGIH (2005); Rozman and Doull (2005); Stelljes (2005); and others.

XI. 	 How can I use nPB as safely as possible? tc "VIII. 	 How can I use
nPB as safely as possible?"

Below are actions that will help nPB users meet the workplace exposure
limit proposed in this rule:

All end uses

All users of nPB should wear appropriate personal protective equipment,
including chemical goggles, flexible laminate protective gloves (e.g.,
Viton, Silvershield) and chemical-resistant clothing.  Special care
should be taken to avoid contact with the skin since nPB, like many
halogenated solvents, can be absorbed through the skin.

Limit worker exposure to solvents to minimize any potential adverse
health effects.  Workers should avoid staying for long periods of time
in areas near where they have been using the solvent.  Where possible,
shorten the period during each day when a worker is exposed.

Use less solvent, or use a different solvent, either alone or in a
mixture with nPB.

Follow all recommended safety precautions specified in the
manufacturer’s MSDS.

Workers should receive safety training and education that includes
potential health effects of exposure to nPB, covering information
included on the appropriate MSDSs, as required by OSHA's Hazard
Communication Standard (29 CFR 1910.1200).

Request a confidential consultation from your State government on all
aspects of occupational safety and health.  You can contact the
appropriate state agency that participates in OSHA’s consultation
program.  These contacts are on OSHA’s web site at     HYPERLINK
"http://www.osha.gov/oshdir/consult.html."
http://www.osha.gov/oshdir/consult.html.   For further information on
OSHA’s confidential consultancy program, visit OSHA’s web page at
HYPERLINK "http://www.osha.gov/html/consultation.html"
http://www.osha.gov/html/consultation.html .

Use the employee exposure monitoring programs and product stewardship
programs where offered by manufacturers and formulators of nPB-based
products.

If the manufacturer or formulator of your nPB-based product does not
have an exposure monitoring program, we recommend that you start your
own exposure monitoring program, and/or request a confidential
consultation from your State government.

 	A medical monitoring program should be established for the early
detection and prevention of acute and chronic effects of exposure to
nPB.  The workers' physician(s) should be given information about the
adverse health effects of exposure to nPB and the workers' potential for
exposure.

Solvent cleaning

For non-aerosol solvent cleaning, follow guidelines in the NESHAP for
halogenated solvents cleaning if you are using nPB.  The equipment and
procedural changes described in the halogenated solvents NESHAP can
reduce emissions, reduce solvent losses and lower the cost of cleaning
with organic solvents.  For more information on the halogenated solvents
NESHAP, visit http://www.epa.gov/ttn/atw/eparules.html and     HYPERLINK
"http://www.epa.gov/ttn/atw/degrea/halopg.html."
http://www.epa.gov/ttn/atw/degrea/halopg.html.

Spray applications

For spray applications (e.g., aerosols), use sufficient ventilation to
meet the recommended 17 ppm WEL.

For ventilation, we recommend that you follow the design guidelines for
ventilation in ACGIH’s Industrial Ventilation: A Manual of Recommended
Practice (ACGIH, 2002).  In particular, the guidelines in Chapter 10.75
are appropriate for spray booths, and the guidelines in Chapter 10.35
are appropriate for laboratory hoods.

The ACGIH Ventilation Manual recommends a minimum flow rate of 150 cubic
feet per minute (cfm) for each sq-ft of opening for a small booth with
at least 4 sq-ft of open face area.  This equates to an average face
velocity of 150 ft/min.  For a large booth, the recommended face
velocity is 100 ft/min for walk-in booths and 100 to 150 ft/min for a
large spray booth where the operator works outside.  In general, the
opening should be kept as small as possible to accommodate the
work-pieces, generally 12 inches wider and taller than the largest piece
of work.  If all spraying is not directed towards the back of the booth
or the booth is too shallow for the size of the pieces being sprayed or
is disruptive air currents are present at the face of the booth, a
greater flow of air will be needed.

We note that these steps are useful for reducing exposure to any
industrial solvent, and not just nPB.

XII.	Statutory and Executive Order Reviews tc "Statutory and Executive
Order Reviews"

	A. 	Executive Order 12866:  Regulatory Planning and Review

	Under Executive Order (EO) 12866   SEQ CHAPTER \h \r 1 (58 FR 51735,
October 4, 1993), this action is a "significant regulatory action.”
It raises novel legal or policy issues arising out of legal mandates,
the President's priorities, or the principles set forth in the Executive
Order.   SEQ CHAPTER \h \r 1  Accordingly, EPA submitted this action to
the Office of Management and Budget (OMB) for review under EO 12866 and
any changes made in response to OMB recommendations have been documented
in the docket for this action.

	  SEQ CHAPTER \h \r 1 In addition, EPA prepared an analysis of the
potential costs and benefits associated with this action.  This analysis
is contained in the document “Analysis of Economic Impacts of nPB
Rulemaking.”  A copy of the analysis is available in the docket for
this action (Ref. EPA-HQ-OAR-2002-0064) and the analysis is briefly
summarized here.  EPA estimates the total costs of the proposed rule to
between $37 and 44.4 million per year, with the health benefits being as
high as $111 million per year.

Paperwork Reduction Act

The information collection requirements in this proposed rule have been
submitted for approval to the Office of Management and Budget (OMB)
under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq.  An
Information Collection Request (ICR) document has been prepared by EPA
(ICR No. 2224.01) and a copy may be obtained from Susan Auby by mail at
Collection Strategies Division; U.S. Environmental Protection Agency
(2822T); 1200 Pennsylvania Ave., NW,  Washington, DC 20460, by email at
<EMAIL_ADDRESS>or by calling<PHONE_NUMBER>.  A copy may
also be downloaded off the internet at   HYPERLINK
"http://www.regulations.gov"  www.regulations.gov . in Docket
EPA-HQ-OAR-2002-0064.

If the provisions of this proposed rule become final, there would be no
new information collection burden.  This proposed rule is an Agency
determination.  It contains no new requirements for reporting or
recordkeeping.  OMB has previously approved the information collection
requirements contained in the existing regulations in subpart G of 40
CFR part 82 under the provisions of the Paperwork Reduction Act, 44
U.S.C. 3501 et seq. and has assigned OMB control number 2060-0226 (EPA
ICR No. 1596.05).  This ICR included five types of respondent reporting
and record-keeping activities pursuant to SNAP regulations:  submission
of a SNAP petition, filing a SNAP//Toxic Substance Control Act (TSCA)
Addendum, notification for test marketing activity, record-keeping for
substitutes acceptable subject to use restrictions, and record-keeping
for small volume uses.

However, if EPA were to finalize the alternate proposal, users of nPB
would have an information collection burden from exposure monitoring and
recordkeeping.  Under the alternate proposal, users of nPB would be
required to monitor worker exposure initially and periodically (usually
every 6 months) and keep records of these exposure data at the facility
for at least three years from the date the samples were taken.  This
data is necessary to ensure that users of nPB are meeting the regulatory
use conditions.  If the data indicates that the use condition is not
being met, it could be used by EPA or citizens in an enforcement action
against the facility.  These data would be considered available to the
public and would not be considered confidential.

The estimated burden of recordkeeping for the entire regulated community
under the alternate proposal is as much as $12.8 million and 24,050
hours per year.  The estimated recordkeeping burden for a typical user
is $96 and 0.18 hours per worker per monitoring event.  We estimate
approximately 1.6 monitoring events per year per worker, assuming that
roughly 60% of exposed workers must be monitored every six months and
40% must be monitored once annually.  We estimate that up to 75,000
workers would be monitored for exposure to nPB.  Costs include the
annual cost of purchasing passive organic exposure monitoring badges,
the annual cost of services for analyzing the resulting exposure, and
the annual cost of reviewing and filing the data up to 2 times per year.

	Burden means the total time, effort, or financial resources expended by
persons to generate, maintain, retain, or disclose or provide
information to or for a Federal agency.  This includes the time needed
to review instructions; develop, acquire, install, and utilize
technology and systems for the purposes of collecting, validating, and
verifying information, processing and maintaining information, and
disclosing and providing information; adjust the existing ways to comply
with any previously applicable instructions and requirements; train
personnel to be able to respond to a collection of information; search
data sources; complete and review the collection of information; and
transmit or otherwise disclose the information.

	An Agency may not conduct or sponsor, and a person is not required to
respond to, a collection of information unless it displays a currently
valid OMB control number.  The OMB control numbers for EPA's regulations
are listed in 40 CFR Part 9 and 48 CFR Chapter 15.

We request comments on the Agency's need for this information, the
accuracy of the provided burden estimates, and any suggested methods for
minimizing respondent burden, including through the use of automated
collection techniques.  Send comments on the ICR to the Director,
Collection Strategies Division; U.S. Environmental Protection Agency
(2822T); 1200 Pennsylvania Ave., NW, Washington, DC 20460; and to the
Office of Information and Regulatory Affairs, Office of Management and
Budget, 725 17th St., N.W., Washington, DC 20503, marked "Attention:
Desk Officer for EPA."  Include the ICR number in any correspondence.
Since OMB is required to make a decision concerning the ICR between 30
and 60 days after [Insert date of publication in the FEDERAL REGISTER],
a comment to OMB is best assured of having its full effect if OMB
receives it by [Insert date 30 days after publication in the FEDERAL
REGISTER].  The final rule will respond to any OMB or public comments on
the information collection requirements contained in this proposal.

C.  	Regulatory Flexibility Act (RFA)

	The Regulatory Flexibility Act (RFA) generally requires an agency to
prepare a regulatory flexibility analysis of any rule subject to notice
and comment rulemaking requirements under the Administrative Procedure
Act or any other statute unless the agency certifies that the rule will
not have a significant economic impact on a substantial number of small
entities.  Small entities include small businesses, small organizations,
and small governmental jurisdictions.  The RFA provides default
definitions for each type of small entity.  Small entities are defined
as: (1) a small business as defined by the Small Business
Administration’s (SBA) regulations at 13 CFR 121.201; (2) a small
governmental jurisdiction that is a government of a city, county, town,
school district or special district with a population of less than
50,000; and (3) a small organization that is any not-for-profit
enterprise which is independently owned and operated and is not dominant
in its field.  However, the RFA also authorizes an agency to use
alternate definitions for each category of small entity, “which are
appropriate to the activities of the agency” after proposing the
alternate definition(s) in the Federal Register and taking comment.  5
USC 601(3) - (5).  In addition, to establish an alternate small business
definition, agencies must consult with SBA’s Chief Counsel for
Advocacy.

	For purposes of assessing the impacts of the proposed rule on small
entities, EPA is proposing to define “small business” as a small
business with less than 500 employees, rather than use the individual
SBA size standards for the numerous NAICS subsectors and codes.  We
believe that no small governments or small organizations are affected by
this rule.  EPA chose to use the alternate definition to simplify the
economic analysis.  This approach slightly reduced the number of small
businesses subject toincluded in our analysis but slightly increased the
percentages of small business significantly impacted in the analysis.
Furthermore, this size standard was set by the Small Business
Administration for all NAICS codes for businesses using nPB-based
adhesives, one of the end uses that would be affected by this rule.  We
solicited comments on the choice of this alternate definition for this
analysis on the June 2003 NPRM, and received no public comments.  We
again request comment on this alternate definition of “small
business.”

	EPA consulted with the Small Business Administration Office of Advocacy
on the alternate small business definition of 500 employees for the June
2003 proposal.  The Office of Advocacy concurred with EPA’s approach.
The number and types of small businesses that would be regulated have
not changed significantly in this NPRM from the June 2003 proposal, and
EPA is proposing the same definition.

	After considering the economic impacts of this proposed rule on small
entities, I certify that this action will not have a significant
economic impact on a substantial number of small entities.  EPA
estimates that up to 4850 small industrial end users currently use nPB
in the end uses addressed by this rule and thus could be subject to the
regulatory impacts of this rule.  This number includes approximately
1470 users of nPB industrial cleaning solvents (e.g., cleaning with
vapor degreasers), 3100 users of nPB-based aerosol solvents, and 280
users of nPB-based adhesives.  Considering together the regulatory
impacts on adhesive and aerosol users that must switch to other
alternatives and the costs to solvent users to implement the recommended
17 ppm exposure limit, we found that up to 258 (8%) small businesses
would experience impacts of 1% or greater of annual sales and no small
businesses would experience impacts of 3% or greater of annual sales.
Based on the relatively small number and percentage of small businesses
that would experience significant impacts, EPA concludes that this rule
would not have a significant economic impact on a substantial number of
small entities.

	In the case of coatings uses, our understanding is that only a single
facility, the Lake City Army Ammunition Plant, is currently using
coatings with nPB as the carrier solvent, and this facility could
continue to use nPB following its current practices.  Therefore, we
consider there to be no economic impact of this rule on coatings users
and have not done further analysis for this end use.

	Types of businesses that would be subject to this proposed rule
include:

Manufacturers of primary metals, where there may be a need to clean off
oil and grease (NAICS subsectors 331).

Manufacturers of fabricated metal parts, including plating, ball and
roller bearings, machined parts, and other metal parts that require oil
and grease to be cleaned off; and manufacturers of ammunition using
coatings or sealants (NAICS subsectors 332, 333, and 339).

Manufacturers of computers and electronic equipment that clean with nPB
cleaning solvents (NAICS subsector 334).

Manufacturers of appliances, electrical equipment, and components that
require oil, grease, and solder flux to be cleaned off (NAICS subsection
335).

Manufacturers of transportation equipment, such as aerospace equipment
that requires cleaning either in a tank or with aerosols, or aircraft
seating, which is assembled using adhesives containing nPB as a carrier
solvent; and ship or boat builders applying  adhesives with nPB (NAICS
subsector 336).

Manufacturers of furniture, including various kinds of furniture with
cushions and countertops assembled using adhesives containing nPB as a
carrier solvent (NAICS subsector 337).

Foam fabricators, who assemble foam cushions or sponges using adhesives
containing nPB as a carrier solvent (NAICS code 326150).

EPA estimates that up to 4850 small industrial end users currently use
nPB in the end uses addressed by this rule and thus could be subject to
the regulatory impacts of this rule.  This number includes approximately
1470 users of nPB industrial cleaning solvents (e.g., cleaning with
vapor degreasers), 3100 users of nPB-based aerosol solvents, and 280
users of nPB-based adhesives.

	In order to consider the resources that affected small businesses have
available to operate and to respond to the proposed regulatory
requirements, EPA compared the cost of meeting the proposed regulatory
requirements to small businesses’ annual sales.  In our analysis for
this proposed rule, we used the average value of shipments for the
products manufactured by the end user as a proxy for sales or revenues,
since these data are readily available from the U.S. Department of
Commerce.  The following tables display the average value of shipments
for different sizes of business and different NAICS subsectors or codes
in the affected industrial sectors.  EPA then used data from these
sources to determine the potential economic impacts of this proposed
rule on small businesses of this proposed rule.

Table 16.  Average Value of Shipments in NAICS Subsectors Performing
Solvent Cleaning,

by Number of Employees at Business

Number of Employees at Business	Average Value of Shipments per Business
($) by NAICS Subsector Code

	331, Primary Metal Mfg	332, Fabricated Metal Products	333, Machinery
334, Computer and Electronic Products	335, Electrical Equipment,
Appliance, and Component Mfg	336, Transport-ation Equipment	337,
Furniture and Related Products	339,Misc. Mfg

1 to 4 employees	368,580	222,973	301,232	345,007	315,772	412,460	180,805
181,876

5 to 9 employees	1,369,866	835,793	1,049,335	1,317,238	1,243,065
1,414,384	712,557	773,320

10 to 19 employees	2,828,531	1,654,147	1,988,048	2,566,913	2,483,327
2,573,352	1,704,272	1,543,581

20 to 49 employees	7,258,463	4,119,582	4,768,137	5,672,245	5,389,945
5,738,739	3,297,360	3,910,203

50 to 99 employees	17,350,990	10,300,841	11,882,524	12,951,836
12,650,236	12,735,583	8,460,846	9,836,121

100 to 249 employees	38,539,490	27,472,772	29,166,421	31,258,875
31,290,638	34,256,544	20,153,844	24,981,108

250 to 499 employees	95,889,945	61,152,558	81,774,945	84,270,454
77,279,974	86,911,454	48,821,903	68,880,502

Avg Value Ship Small Businesses in Sub-sector	11,935,698	3,812,656
5,359,829	8,261,788	9,539,205	11,029,561	2,536,805	2,923,741

Avg Value Ship ALL Businesses in Subsector	28,783,017	4,168,836
6,620,907	20,810,094	13,417,905	45,029,773	2,875,473	3,857,370

Avg Value Shipments Subset Small Businesses using nPB	22,311,696
6,814,736 	9,337,066	11,246,045	12,066,562	13,422,547	5,178,300
5,461,637

1 Aerosol solvents are used in NAICS subsectors 334, 335 and 336.
Non-aerosol solvents are used in all seven NAICS subsectors.

2 “d” designates “Data withheld to avoid disclosing data of
individual companies; data are included in higher level totals.”  The
average value of shipments for businesses estimates those values marked
with “d,” and thus may be overestimated or underestimated.

Table 17. Average Value of Shipments in NAICS Categories

Using nPB as a Carrier Solvent in Adhesives, by Number of Employees at
Business

Number of Employees at Business	Average Value of Shipments per Small
Business ($) by NAICS Sub Sector

	337121,

Upholstered household furniture

	337110,

Wood kitchen cabinet and counter tops	326150,

Urethane and other foam products (except polystyrene)	336360,

Motor vehicle seating and interior trim	337124,

Metal household furniture

1 to 4 employees	234,345	156,833	496,318	425,863	187,950

5 to 9 employees	963,021	622,744	1,305,183	1,728,132	903,393

10 to 19 employees	1,771,416	1,141,119	3,152,283	3,082,486	1,431,480

20 to 49 employees	3,653,623	2,619,197	6,615,331	5,508,370	3,538,684

50 to 99 employees	8,089,968	7,386,365	13,281,000	14,088,500	7,547,536

100 to 249 employees	17,502,175	17,151,091	31,524,872	44,310,286
19,821,719

250 to 499 employees	40,250,813	55,982,674	64,119,800	123,803,610	D(1)

Avg Small Businesses  in Sub sector	3,588,297	1,150,768	10,472,992
12,542,725	3,141,720

Avg ALL Businesses in Sub sector	5,490,101	1,475,602	11,110,822
44,808,573	5,239,747

Avg Subset Small Businesses using nPB	 11,519,540 	5,999,622 	18,950,068
	12,019,847 	20,401,301

 (1)“d” designates “Data withheld to avoid disclosing data of
individual companies; data are included in higher level totals.”  The
average value of shipments for businesses estimates those values marked
with “d,” and thus may be overestimated or underestimated.

	This proposed rule requires that nPB would be unacceptable for use in
adhesives and aerosols.  The available alternatives identified include
adhesive formulations based on water, methylene chloride, or flammable
solvents such as acetone and aerosol formulations of flammable solvents,
combustible solvents, blends of trans-dichloroethylene and HFEs or HFCs,
and HCFC-225ca/cb.  We considered various aspects of the cost of
switching to other alternatives, including the cost of meeting OSHA
requirements and the cost of the alternative adhesive.

	We estimate that up to 9 small businesses using nPB-based adhesives, or
roughly 3% of the 280 or so small businesses that use nPB-based
adhesives, would experience a cost increase (i.e., an impact) of greater
than 1.0% of annual sales, and no small businesses would experience an
impact of greater than 3% of annual sales if this proposed rule became
final.  For small businesses using nPB-based aerosols, we estimate that
approximately 249 would experience a cost increase of greater than 1.0%
of annual sales.  This equates to roughly 8% of the 3100 or so small
businesses currently using nPB-based aerosol solvents.  No small
businesses using aerosols would experience an impact of greater than 3%
of annual sales.  Approximately five percent of all 4850 or so small
businesses choosing to use nPB would experience an impact of greater
than 1.0% of annual sales and no small businesses would experience an
impact of greater than 3.0% of annual sales.  Because of the small total
number and small percentage of affected businesses that would experience
an impact of greater than either 1.0% or 3.0% of annual sales, EPA does
not consider this rule to have a significant impact on a substantial
number of small businesses.

	The Agency analyzed the cost impacts of implementing the exposure limit
for solvent cleaning uses in order to provide additional information
about potential effects on small businesses.  Businesses using nPB-based
cleaning solvents for metals cleaning, electronics cleaning, or
precision cleaning would experience significant cost benefits by
reducing spending on solvent.

	Considering together the regulatory impacts on adhesive and aerosol
users that must switch to other alternatives and the costs to solvent
users to implement the recommended 17 ppm exposure limit, we found that
up to 258 (8%) small businesses would experience impacts of 1% or
greater of annual sales and no small businesses would experience impacts
of 3% or greater of annual sales.  Based on the relatively small number
and percentage of small businesses that would experience significant
impacts, EPA concludes that this rule would not have a significant
economic impact on a substantial number of small entities.

	We also analyzed the potential small business impacts of the alternate
proposal.  Under the alternate proposal, users would have to: (1) meet a
workplace exposure limit of 17 ppm on an eight-hour time-weighted
average, (2) monitor workers’ exposure to nPB using a personal
breathing zone sampler on an eight-hour time-weighted average initially
and periodically (every 6 months or longer, depending on the
concentration during initial monitoring), and (3) keep records of the
worker exposure data on site at the facility for at least three years
from the date of the measurement.  We assume that the cost of following
the alternate proposal is the cost of installing ventilation for
aerosols and adhesives or emission controls for solvent cleaning, the
cost of using personal protective equipment, and the cost of monitoring
worker exposure.  Approximately 67 to 387 aerosol solvent users (2 to 13
percent), 25 to 54 adhesive users (9 to 19 percent), no solvent cleaning
users, and 2.6 to 12.6 percent of all 4850 or so small businesses would
experience impacts of greater than 1% of annual sales if they chose to
meet nPB the proposed requirements with the applicable use conditions
rather than switching to another ODS substitute.  Four to nine users of
nPB-based adhesives, or less than 1% of all small businesses, would
experience impacts of 3% or greater of annual sales under the alternate
proposal.  Based on this analysis, the alternate proposal would not
create a significant adverse impact on a significant number of small
entities.

	Although this proposed rule would not have a significant economic
impact on a substantial number of small entities if it became final, EPA
nonetheless has tried to reduce the impact of this rule on small
entities.  Before selecting the regulatory option in this proposed rule,
we considered a number of regulatory options, such as:

•	Placing a narrowed use limit on the use of nPB in adhesives and
aerosols that would allow its use only in those cases where alternatives
are technically infeasible due to performance or safety issues.  This
would have required testing, recordkeeping, and some installation of
capital equipment.

Requiring that when nPB is used in adhesives or aerosols, it must be
used with local ventilation equipment and personal protective equipment.
  This would have required further installation of capital equipment,
without necessarily protecting workers as thoroughly as a required
workplace exposure limit or requiring a switch to another alternative.

Requiring that users clean metal, electronics, or other parts with nPB
in low-emission air-tight vapor degreasing equipment.

•	Requiring that users clean metal, electronics, or other parts with
nPB in vapor degreasing equipment that meets the requirements of the
national emission standards for halogenated solvent cleaning.

Prohibiting the use of nPB in all end uses.

Retaining the previously proposed requirement for a limit on iPB content
in nPB formulations.

The costs of a number of these options are included in EPA’s analysis
(EPA, 2006).

	In developing our regulatory options, we considered information we
learned from contacting small businesses using or selling nPB.  EPA
staff visited the site of a small business using nPB for cleaning
electronics.  We contacted several fabricators of foam cushions that
have used adhesives containing nPB.  We participated in meetings with a
number of adhesive manufacturers and users of adhesives in furniture
construction.  We developed a fact sheet and updated our program web
site to inform small businesses about the proposed rule and to request
their comments.

	We continue to be interested in the potential impacts of the proposed
rule on small entities and welcome comments on issues related to such
impacts.

	D.	Unfunded Mandates Reform Act

	Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public Law
104-4, establishes requirements for Federal agencies to assess the
effects of their regulatory actions on State, local, and tribal
governments and the private sector.  Under section 202 of the UMRA, EPA
generally must prepare a written statement, including a cost-benefit
analysis, for proposed  and final rules with "Federal mandates" that may
result in expenditures to State, local, and tribal governments, in the
aggregate, or to the private sector, of $100 million or more in any one
year. Before promulgating an EPA rule for which a written statement is
needed, section 205 of the UMRA generally requires EPA to identify and
consider a reasonable number of regulatory alternatives and adopt the
least costly, most cost-effective or least burdensome alternative that
achieves the objectives of the rule.  The provisions of section 205 do
not apply when they are inconsistent with applicable law.  Moreover,
section 205 allows EPA to adopt an alternative other than the least
costly, most cost-effective or least burdensome alternative if the
Administrator publishes with the final rule an explanation why that
alternative was not adopted.  Before EPA establishes any regulatory
requirements that may significantly or uniquely affect small
governments, including tribal governments, it must have developed under
section 203 of the UMRA a small government agency plan.  The plan must
provide for notifying potentially affected small governments, enabling
officials of affected small governments to have meaningful and timely
input in the development of EPA regulatory proposals with significant
Federal intergovernmental mandates, and informing, educating, and
advising small governments on compliance with the regulatory
requirements.  EPA has determined that this rule does not contain a
Federal mandate that may result in expenditures of $100 million or more
for State, local, and tribal governments, in the aggregate, or the
private sector in any one year.  This proposed rule does not affect
State, local, or tribal governments.  The enforceable requirements of
the rule for the private sector affect a number of end users in
manufacturing.  The estimated cost of the proposed requirements for the
private sector is approximately $37.0 to 44.4 million per year, and the
alternate proposal would cost the private sector approximately $ 49.6 to
76.2 million per year.  Therefore, the impact of this rule on the
private sector is less than $100 million per year.  Thus, this rule is
not subject to the requirements of sections 202 and 205 of the UMRA.
EPA has determined that this rule contains no regulatory requirements
that might significantly or uniquely affect small governments.  This
regulation applies directly to facilities that use these substances and
not to governmental entities.

	E.	Executive Order 13132: Federalism

	Executive Order 13132, entitled “Federalism” (64 FR 43255, August
10, 1999), requires EPA to develop an accountable process to ensure
“meaningful and timely input by State and local officials in the
development of regulatory policies that have federalism implications.”
 “Policies that have federalism implications” is defined in the
Executive Order to include regulations that have “substantial direct
effects on the States, on the relationship between the national
government and the States, or on the distribution of power and
responsibilities among the various levels of government.”

	This proposed rule does not have federalism implications.  It will not
have substantial direct effects on the States, on the relationship
between the national government and the States, or on the distribution
of power and responsibilities among the various levels of government, as
specified in Executive Order 13132.  This regulation applies directly to
facilities that use these substances and not to governmental entities.
Thus, Executive Order 13132 does not apply to this rule.

	F.	Executive Order 13175:  Consultation and Coordination with Indian
Tribal

Governments

	Executive Order 13175, entitled “Consultation and Coordination with
Indian Tribal Governments” (65 FR 67249, November 6, 2000), requires
EPA to develop an accountable process to ensure “meaningful and timely
input by tribal officials in the development of regulatory policies that
have tribal implications.”  “Policies that have tribal
implications” is defined in the Executive Order to include regulations
that have “substantial direct effects on one or more Indian tribes, on
the relationship between the Federal government and the Indian tribes,
or on the distribution of power and responsibilities between the Federal
government and Indian tribes.”

	This proposed rule does not have tribal implications.  It will not have
substantial direct effects on tribal governments, on the relationship
between the Federal government and Indian tribes, or on the distribution
of power and responsibilities between the Federal government and Indian
tribes, as specified in Executive Order 13175.

	This proposed rule would not significantly or uniquely affect the
communities of Indian tribal governments, because this regulation
applies directly to facilities that use these substances and not to
governmental entities.  Thus, Executive Order 13175 does not apply to
this proposed rule.

Executive Order 13045:  Protection of Children from Environmental Health
and Safety Risks

	Executive Order 13045:  “Protection of Children from Environmental
Health Risks and Safety Risks” (62 FR 19885, April 23, 1997) applies
to any rule that: (1) is determined to be "economically significant" as
defined under Executive Order 12866, and (2) concerns an environmental
health or safety risk that EPA has reason to believe may have a
disproportionate effect on children.  If the regulatory action meets
both criteria, the Agency must evaluate the environmental health or
safety effects of the planned rule on children, and explain why the
planned regulation is preferable to other potentially effective and
reasonably feasible alternatives considered by the Agency.

	This proposed rule is not subject to the Executive Order because it is
not economically significant as defined in Executive Order 12866, and
because the Agency does not have reason to believe the environmental
health or safety risks addressed by this action present a
disproportionate risk to children.  The exposure limits and
acceptability listings in this proposed rule apply to the workplace.
These are areas where we expect adults are more likely to be present
than children, and thus, the agents do not put children at risk
disproportionately.

	Further, this proposed rule provides both regulatory restrictions and
recommended exposure guidelines based upon toxicological studies in
order to reduce risk of exposure to a reproductive toxin, nPB.  This
proposed rule is not subject to Executive Order 13045 because it is not
economically significant as defined in Executive Order 12866 and because
the Agency does not have reason to believe the environmental health or
safety risks addressed by this action present a disproportionate risk to
children.  The public is invited to submit or identify peer-reviewed
studies and data, of which the agency may not be aware, that assessed
results of early life exposure to nPB.

	H. 	Executive Order 13211:  Actions that Significantly Affect Energy
Supply, Distribution, or Use

	This rule is not a “significant energy action” as defined in
Executive Order 13211, “Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use” (66 FR 28355
(May 22, 2001)) because it is not likely to have a significant adverse
effect on the supply, distribution, or use of energy.  This action would
impact manufacturing of various metal, electronic, medical, and optical
products cleaned with solvents containing nPB and products made with
adhesives containing nPB.  Further, we have concluded that this rule is
not likely to have any adverse energy effects.

	I.	National Technology Transfer and Advancement Act

	As noted in the proposed rule, Section 12(d) of the National Technology
Transfer and Advancement Act of 1995 ("NTTAA"), Pub L. No. 104-113, §
12(d) (15 U.S.C. 272 note) directs EPA to use voluntary consensus
standards in its regulatory activities unless to do so would be
inconsistent with applicable law or otherwise impractical.  Voluntary
consensus standards are technical standards (e.g., materials
specifications, test methods, sampling procedures, and business
practices) that are developed or adopted by voluntary consensus
standards bodies. The NTTAA directs EPA to provide Congress, through
OMB, explanations when the Agency decides not to use available and
applicable voluntary consensus standards.

	This action does not involved technical standards. Therefore, EPA did
not consider the use of any voluntary consensus standards.  We note that
the American Conference of Governmental Industrial Hygienists (ACGIH),
although it sets voluntary standards, is not a voluntary consensus
standards body.  Therefore, use of a proposed or final workplace
exposure limit from the ACGIH is not subject to the NTTAA.

XIII.	References tc "X.	References"

	The documents below are referenced in the preamble.  All documents are
located in the Air Docket at the address listed in section I.B.1 at the
beginning of this document.  Unless specified otherwise, all documents
are available electronically through the Federal Docket Management
System, Docket # EPA-HQ-OAR-2002-0064.  Some specific items are
available only in hard copy in dockets A-2001-07 or A-92-42 (legacy
docket numbers for SNAP nPB rule and for SNAP program and submissions).
Numbers listed after the reference indicate the docket and item numbers.

What criteria did EPA consider in preparing this proposal?

Fabricant, 2003.  Memo to Acting Administrator, Marianne L. Horinko.
2003.  EPA’s Authority to Impose Mandatory Controls to Address Global
Climate Change under the Clean Air Act, from Robert E. Fabricant.

ICF, 2006a.  ICF Consulting.  Risk Screen on Substitutes for
Ozone-Depleting Substances for Adhesive, Aerosol Solvent, and Solvent
Cleaning Applications.  Proposed Substitute:  n-Propyl Bromide.  April
18, 2006.

Availability

Harper, 2005.  Telephone call from M. Sheppard, EPA to Dr. S. Harper,
ATK. Re: Availability of other methyl chloroform substitutes for the
Lake City Army Ammunition Plant.  October 11, 2005.

IBSA, 2002.    SEQ CHAPTER \h \r 1 Record of September 5, 2002 Meeting
with the International Brominated Solvents Association Inc.  (A-2001-07,
II-D-60)

IRTA, 2000.    SEQ CHAPTER \h \r 1 Alternative Adhesive Technologies in
the Foam Furniture and Bedding Industries: A Cleaner Technologies
Substitution Assessment, Cost and Performance Evaluation.  Michael
Morris and Katy Wolf, Institute for Research and Technical Assistance.
Prepared for the U.S. EPA Office of Pollution Prevention Technology,
June 2000. (A-2001-07, II-D-70)

Seilheimer, 2001.    SEQ CHAPTER \h \r 1 Telephone Log of April 4, 2001
call between Margaret Sheppard, EPA, and Bob Seilheimer, Imperial
Adhesives.  (A-2001-07, II-B-5)

Williams, 2005.  Notes on conversation of Ed Williams, Technical
Manager, LPS Laboratories, and Margaret Sheppard, EPA.   November 3,
2005

Ozone-Depletion Potential and Other Environmental Impacts

Atmospheric and Environmental Research, Inc, 1995:  Estimates of the
Atmospheric Lifetime, Global Warming Potential and Ozone Depletion
Potential of n-Propyl Bromide.  Independent study prepared for Albemarle
Corporation.  (A-2001-07, II-D-17)

ATSDR, 1994. Toxicological Profile For Acetone.   Agency for Toxic
Substances and Disease Registry.  May, 1994.  Available at   HYPERLINK
"http://www.atsdr.cdc.gov/toxprofiles/tp21-c5.pdf"
http://www.atsdr.cdc.gov/toxprofiles/tp21-c5.pdf

ATSDR, 1996. Toxicological Profile For 1,2-Dichloroethene.   Agency for
Toxic Substances and Disease Registry.  August, 1996.  Available at
HYPERLINK "http://www.atsdr.cdc.gov/toxprofiles/tp87-c5.pdf"
http://www.atsdr.cdc.gov/toxprofiles/tp87-c5.pdf

ATSDR, 1997. Toxicological Profile For Trichloroethylene.   Agency for
Toxic Substances and Disease Registry.  September, 1997.  Available at
http://www.atsdr.cdc.gov/toxprofiles/tp19-c5.pdf

ATSDR, 2004.  Draft Toxicological Profile For 1,1,1-Trichloroethane.
Agency for Toxic Substances and Disease Registry.  September, 2004.
Updated draft for comment. Available at   HYPERLINK
"http://www.atsdr.cdc.gov/toxprofiles/tp70-c6.pdf"
http://www.atsdr.cdc.gov/toxprofiles/tp70-c6.pdf

	EDSTAC, 1998.  Final Report of the Endocrine Disruptor Screening and
Testing Advisory Committee.  August, 1998.

Fisher Scientific, 2001.  Material Safety Data Sheet for acetone.
Updated March 19, 2001.  Available at   HYPERLINK
"http://www.mhatt.aps.anl.gov/dohn/msds/acetone.html"
http://www.mhatt.aps.anl.gov/dohn/msds/acetone.html

Geiger et al., 1998.  Geiger, D.L., Call, D.J., and Brooke, L.T.  1988.
Acute Toxicities of Organic Chemicals to Fathead Minnows (Pimephales
promelas), Vol. 4.  In: Center for Lake Superior Environmental Stud.,
Univ.of Wisconsin-Superior, Superior, WI I:355.  (Summarized in ICF,
2004a)

HSDB, 2004.  Hazardous Substances Databank File for 1-Bromopropane.
Accessed 1/2004 from the World Wide Web at
http://toxnet.nlm.nih.gov/cgi-bin/sis/search/f?./temp/~dLwM9e:1
(Summarized in ICF, 2004a)

ICF, 2004a.  ICF Consulting.  Memo to E. Birgfeld, EPA, re: nPB Aquatic
Toxicity.  January 19, 2004.

LaGrega, M., Buckingham, P., Evans, J., and Environmental Resources
Management, 2001.  Hazardous Waste Management.  Second Edition.
McGraw-Hill, New York, NY.  2001.

Linnell, 2003.  Comments from the Electronics Industry Alliance.
(EPA-HQ-OAR-2002-0064 items -0043, -0044, and -0045)

NPS, 1997.  Irwin, R.J., M. VanMouwerik, L. Stevens, M.S. Seese, and W.
Basham.  1997. Environmental Contaminants Encyclopedia.  National Park
Service,Water Resources Division, Fort Collins, Colorado.

Steminiski, 2003.  July 27, 2003 Comment from J. Steminiski, Ph. D.
(EPA-HQ-OAR-2002-0064-0035 and -0043)

U.S. Economic Census, 2002a.  General Summary:  2002.  Subject Series.
Report No. EC02-31SG-1, October, 2005.  U.S. Census Bureau.

U.S. Economic Census, 2002b.  U.S. Economic Census for Island Areas,
2002.  Report for Northern Marianas Islands, Rpt. No.  IA02-00A-NMI,
May, 2004.  U.S. Census Bureau.

U.S. Economic Census, 2002c.  U.S. Economic Census for Island Areas,
2002.  Report for Guam, Rpt. No. IA02-00A-GUAM, March, 2005.  U.S.
Census Bureau.

U.S. Economic Census, 2002d.  U.S. Economic Census for Island Areas,
2002.  Report for Virgin Islands, Rpt. No. IA02-00A-VI , April, 2005.
U.S. Census Bureau.

U.S. Economic Census, 2002e.  U.S. Economic Census for Island Areas,
2002.  Report for American Samoa, Rpt. No. IA02-00A-AS, April, 2005.
U.S. Census Bureau.

U.S. Economic Census, 2002f.  U.S. Economic Census for Island Areas,
2002.  Report for Puerto Rico: Manufacturing, Rpt. No. IA02-00I-PRM,
October, 2005. U.S. Census Bureau.

US EPA, 1980.  Ambient Water Quality Criteria for Dichloroethylenes. EPA
440/5-80-041  October, 1980.  Available at   HYPERLINK
"http://www.epa.gov/waterscience/pc/ambientwqc/dichloroethylenes80.pdf"
http://www.epa.gov/waterscience/pc/ambientwqc/dichloroethylenes80.pdf

US EPA, 1992.  Hazard Assessment Guidelines for Listing Chemicals on the
Toxic Release Inventory, Revised Draft.  Washington, DC:  Office of
Pollution, Prevention and Toxics. As referenced in ICF, 2004f.

US EPA, 1994b.  Chemical Summary for Methyl Chloroform, prepared by
Office of Pollution Prevention and Toxics, August, 1994.

WMO, 2002:  Scientific Assessment of Ozone Depletion: 2002, Global Ozone
Research and Monitoring Project – Report No. 47, Geneva, 2003 Full
report available online at    HYPERLINK
"http://esrl.noaa.gov/csd/assessments/"
http://esrl.noaa.gov/csd/assessments/    (A-2001-07, II-A-20)

Wuebbles, Donald J.  2002.  “The Effect of Short Atmospheric Lifetimes
on Stratospheric Ozone.”  Written for Enviro Tech International, Inc.
Department of Atmospheric Sciences, University of Illinois-Urbana.
(A-2001-07, II-D-29)

Flammability and Fire Safety

	BSOC, 2000.  February 1, 2000 Tabulation of Flammability Studies on
n-Propyl Bromide from the Brominated Solvents Committee, and other
information on flammability of n-propyl bromide.  (A-2001-07, II-D-45)

Miller, 2003.  Albemarle Corporation comments- Flash Point Data for
n-Propyl Bromide.  (EPA-HQ-OAR-2002-0064-0040)

Morford, 2003a.  Enviro Tech International Comment re Section IV D
Flammability with Exhibits (7/25/03) (EPA-HQ-OAR-2002-0064-0030 and
EPA-HQ-OAR-2002-0064-0031)

Morford, 2003b.  Enviro Tech Int. Flammability of nPB & Comparison With
Methylene Chloride- Additional Comments on Flammability (7/29/03)
(EPA-HQ-OAR-2002-0064-0036)

Shubkin, 2003.  R. Shubkin, Poly Systems, EPA received 7/23/03 Re:
Comment on Flammability of n-Propyl Bromide as Discussed in Proposed
Rule Published in Federal Register (EPA-HQ-OAR-2002-0064-0025)

Weiss Cohen, 2003.  T. Weiss Cohen, Dead Sea Bromine Group,7/31/2003
Comment to Federal Register Proposed Rules of June 3, 2003, on
Protection of Stratospheric Ozone: Listing of Substitutes for
Ozone-Depleting Substances - n-Propyl Bromide
(EPA-HQ-OAR-2002-0064-0053)

Human Health; Derivation of Workplace Exposure Limit and Community
Exposure Guideline

ACGIH, 1991.  Skin Notation Documentation for Methyl Chloride. Available
online at www.acgih.org.

ACGIH, 2005.  Documentation for Threshold Limit Value for
1-Bromopropane.  2005.  Available online at www.acgih.org.

Beck and Caravati, 2003.   Neurotoxicity associated with 1-bromopropane
exposure.Utah Poison Control Center, University of Utah, Salt Lake City,
UT. J Toxicology Clinical Toxicology  41(5):729. (Abstract from
conference). 2003.

		CERHR, 2002a.  NTP- Center for the Evaluation of Risks to Human
Reproduction Expert Panel Report on the Reproductive and Developmental
Toxicity of 1-Bromopropane [nPB].  March 2002.  (A-2001-07, II-A-11)

CERHR, 2002b.  NTP- Center for the Evaluation of Risks to Human
Reproduction Expert Panel Report on the Reproductive and Developmental
Toxicity of 2-Bromopropane [iPB].  March 2002.  (A-2001-07, II-A-12)

CERHR, 2003a.  NTP- CERHR Monograph on the Potential Human Reproductive
and Developmental Effects of 1-Bromopropane.  October 2003.

CERHR, 2003b.  NTP- CERHR Monograph on the Potential Human Reproductive
and Developmental Effects of 2-Bromopropane.  October 2003.

CERHR, 2004a. NTP-CERHR Expert Panel report on the reproductive and
developmental toxicity of 1-bromopropane.  Center for the Evaluation of
Risks to Human Reproduction. Repro Toxicol. Vol.18, pp.157-188.  2004.

CERHR, 2004b.  NTP-CERHR Expert Panel report on the reproductive and
developmental toxicity of 2-bromopropane. Boekelheide, et al. Repro
Toxicol. Vol.18, pp.189-217.  2004.

ClinTrials, 1997a.  A 28-Day Inhalation Study of a VaporFormulation of
ALBTA1 in the Albino Rat.  Report No. 91189.  Prepared by ClinTrials
BioResearch Laboratories, Ltd., Senneville, Quebec, Canada.  May 15,
1997.  Sponsored by Albemarle Corporation, Baton Rouge, LA. (A-91-42,
X-A-4)

ClinTrials, 1997b.  ALBTA1: A 13-Week Inhalation Study of a Vapor
Formulation of ALBTA1 in the Albino Rat.  Report No. 91190.   Prepared
by ClinTrials BioResearch Laboratories, Ltd., Senneville, Quebec,
Canada.  February 28, 1997.  Sponsored by Albemarle Corporation, Baton
Rouge, LA. (A-91-42, X-A-5)

Dunson et al, 2002.  Dunson, D., Colombo, and B., Baird, D. Changes with
age in the level and duration of fertility in the menstrual cycle.
Human Reproduction, Vol. 17, No. 5, pp. 1399-1403, 2002.

Elf Atochem, 1995.  Micronucleus Test by Intraperitoneal Route in Mice.
n-Propyl Bromide.  Study No. 12122 MAS.  Study Director, Brigitte
Molinier.  Study performed by Centre International de Toxoicologie,
Misery, France, September 6, 1995.  (A-91-42, X-A-9)

Fueta et al., 2002.  Y. Fueta, K. Fukunaga, T. Ishidao, H. Hori.
Hyperexcitability and changes in activities of Ca2+/calmodulin-dependent
kinase II and mitogen-activated protein kinase in the hippocampus of
rats exposed to 1-bromopropane.  2002.  Life Sciences 72 (2002) 521-529.

Fueta et al., 2004. Y. Fueta, T. Fukuda, T. Ishidao, H. Hori.
Electrophysiology and immunohistochemistry in the hippocampal CA1 and
the Dentate Gyrus of Rats Chronically exposed to 1-Bromopropane, a
Substitute for Specific Chlorofluorocarbons.  Neuroscience 124 (2004)
593-603.

	Honma et al., 2003.  Honma, T, Suda M, Miyagawa M. “Inhalation of
1-bromopropane causes excitation in the central nervous system of male
F344 rats.” Neurotoxicology. 2003 Aug; 24 (4-5):563-75.

Huntingdon Life Sciences, 2001. A Developmental Toxicity Study in Rat
Via Whole Body Inhalation Exposure. (A-2001-07, II-D-27)

ICF, 2002a.  Risk Screen for Use of N-Propyl Bromide.  ICF Consulting.
Prepared for U.S. EPA, May, 2002. (EPA-HQ-OAR-2002-0064-0006 through
-0012)

ICF, 2003.  ICF Consulting.  General Population Exposure Assessment for
N-Propyl Bromide.  June 03, 2003.  (EPA-HQ-OAR-2002-0064-0011)

ICF, 2004b.  ICF Consulting.  External Expert Review Panel on N-Propyl
Bromide.  December 13, 2004.

ICF, 2006a.  ICF Consulting.  Risk Screen on Substitutes for
Ozone-Depleting Substances for Adhesive, Aerosol Solvent, and Solvent
Cleaning Applications.  Proposed Substitute:  n-Propyl Bromide.  April
18, 2006.  Attachments:  A, Determination of an AEL; B, Derivation of an
RfC; C, Evaluation of the Global Warming Potential; D, Occupational
Exposure Analysis for Adhesive Applications; E, Occupational Exposure
Analysis for Aerosol Solvent Applications; F, General Population
Exposure Assessment for n-Propyl Bromide

ICF, 2006b.  ICF Consulting.  Revised Memorandum regarding RTI
Metabolism Study on nPB.  April, 2006.

ICF, 2006c.  ICF Consulting.  Evaluation of Memorandum from Dr. M.
Stelljes.  April, 2006.

Ichihara et al., 1998.  Ichihara M., Takeuchi Y., Shibata E., Kitoh J.,
et al. Neurotoxicity of 1-Bromopropane.  1998.  Translated by Albemarle
Corporation. (A-91-42, X-A-33)

Ichihara G., Jong X., Onizuka J., et al,. 1999.  Histopathological
changes of nervous system and reproductive organ and blood biochemical
findings in rats exposed to 1_bromopropane.  (Abstract only)  Abstracts
of the 72nd Annual Meeting of Japan Society for Occupational Health.
May 1999. Tokyo.  (A-2001-07, II-A-15)

Ichihara G., Kitoh J., Yu, X., et al., 2000. 1-Bromopropane, an
alternative to ozone layer depleting solvents, is dose-dependently
neurotoxic to rats in long-term inhalation   exposure.  Toxicol Sciences
55:116-123.  (A-2001-07, II-A-8)

Ichihara G. et al., 2002.  Neurological Disorders in Three Workers
Exposed to 1-Bromopropane.  J Occu. Health 44:1-7.  (A-2001-07, II-D-64)

Ichihara et al., 2004a.  G. Ichihara, W. Li, X. Ding, S. Peng, X. Yu, E.
Shibata, T. Yamada, H. Wang, S. Itohara, S. Kanno, K. Sakai, H. Ito, K.
Kanefusa, and Y. Takeuchi.  A Survey on Exposure Level, Health Status,
and Biomarkers in Workers Exposed to 1-Bromopropane.   Am Jrnl of Ind
Med 45:63–75 (2004)

Ichihara et al., 2004b. Gaku Ichihara, Weihua Li, Eiji Shibata, Xuncheng
Ding, Hailan Wang, Yideng Liang, Simeng Peng, Seiichiro Itohara,
Michihiro Kamijima, Qiyuan Fan, Yunhui Zhang, Enhong Zhong, Xiaoyun Wu,
William M. Valentine, and Yasuhiro Takeuchi.  Neurological Abnormalities
in Workers of 1-Bromopropane Factory.  Env’l Health Perspectives, 30
June 2004.

Ishidao et al., 2002.  Ishidao T, Kunugita N, Fueta Y, Arashidani K,
Hori H. Effects of inhaled 1-bromopropane vapor on rat metabolism.
Toxicol Lett. 2002 Aug 5;134(1-3):237-43

	Majersik et al., 2004.  Chronic Exposure to 1-Bromopropane Associated
with Spastic Paraparesis and Distal Neuropathy: A Report of Six Foam
Cushion Gluers.  Poster paper from 129th Annual Meeting of the American
Neurological Association, Toronto.  October, 2004

Majersik et al, 2005.  “Spastic Paraparesis and Distal Neuropathy
Associated with Chronic Exposure to 1BP,” Presentation by Drs. J.
Majersik, M. Caravati, and J. Steffens at the North American Congress of
Clinical Toxicologists.  September 14, 2005.

Miller, 2005.  “1-Bromopropane:  A Private Neurological Practice
Experience in 2000,” Presentation by Dr. J. M. Miller, at the North
American Congress of Clinical Toxicologists.  September 14, 2005

NAS, 1983.  The National Academies of Science, Risk Assessment in the
Federal Government: Managing the Process, 1983.  Available online at
HYPERLINK "http://newton.nap.edu/catalog/366.html"
http://newton.nap.edu/catalog/366.html  (Executive summary in docket as
EPA-HQ-OAR-2002-0064-xxxx)

Nemhauser, 2005.  “Bromopropane:  A Health Hazard Evaluation
Revisited”  Presentation by Dr. J. Nemhauser, U.S Public Health
Service, Centers for Disease Control & Presentation at the North
American Congress of Clinical Toxicologists.  September 14, 2005.

NIOSH, 2003a.  NIOSH Health Hazard Evaluation Report #99-0260-2906  Marx
Industries, Inc. Sawmills, NC Available online at   HYPERLINK
"http://www.cdc.gov/niosh/hhe/reports/pdfs/1999-0260-2906.pdf"
http://www.cdc.gov/niosh/hhe/reports/pdfs/1999-0260-2906.pdf .

NTP, 2003.  Results of 13-week Inhalation Testing by the National
Toxicology Program.  Available at   HYPERLINK
"http://ntp-apps.niehs.nih.gov/ntp_tox/"
http://ntp-apps.niehs.nih.gov/ntp_tox/

	index.cfm?fuseaction=ntpsearch.searchresults&searchterm=106-94-5

OEHHA, 2006.  State Of California Environmental Protection Agency,
Office Of Environmental Health Hazard Assessment.  Chemicals Known To
The State To Cause Cancer Or Reproductive Toxicity. June 9, 2006

Raymond and Ford, 2005.  “Clinical Case Presentations from a Foam
Furniture Fabrication Plant in North Carolina,” Presentation by Drs.
Larry Raymond and Marsha Ford at the North American Congress of Clinical
Toxicologists.  September 14, 2005

Risotto, 2003.  Comments of the Halogenated Solvents Industry Alliance
on nPB proposed rule.  June, 2003.  (EPA-HQ-OAR-2002-0064-0050)

Rodricks, 2002.  October 21, 2002 remarks from Dr. J. Rodricks, Environ,
to R. Morford, Enviro Tech International concerning derivation of an OEL
for n-propyl bromide with cover letter to EPA from Enviro Tech
International (A-2001-07, II-D-65)

Rozman and Doull, 2002.  “Derivation of an Occupational Exposure Limit
for n-Propyl Bromide Using an Improved Methodology” App Occu. Env.
Hyg. 17: 711-716 (A-2001-07, II-D-63)

Rozman and Doull, 2005.  Presentation by Drs. Rozman and Doull at the
North American Congress of Clinical Toxicologists.  September 14, 2005.

RTI, 2005.  Report on uptake and metabolism of 1-bromopropane in rats
and mice.  Research Triangle Institute report for the National
Toxicology Program.  June, 2005.

Sekiguchi S, Suda M, Zhai YL, Honma T., “Effects of 1-bromopropane,
2-bromopropane, and 1,2-dichloropropane on the estrous cycle and
ovulation in F344 rats.” Toxicol Lett 2002 Jan 5;126(1):41-9
(A-2001-07, II-D-39)

SLR International, 2001. “Inhalation Occupational Exposure Limit for
n-Propyl Bromide.” Prepared for Enviro Tech International, Inc. 2001.
(A-2001-07, II-D-15)

Sohn et al., 2002.  Sohn YK, Suh JS, Kim JW, Seo HH, Kim JY, Kim HY, Lee
JY, Lee SB, Han JH, Lee YM, Lee JY. “A histopathologic study of the
nervous system after inhalation exposure of 1-bromopropane in rat.”
Toxicol Lett. 2002 May 28;131(3):195-201.

Stelljes and Wood, 2004.  Stelljes, M., Wood, R.  Development of an
occupational exposure limit for n-propylbromide using benchmark dose
methods.  Regulatory Toxicology and Pharmacology 40 (2004) 136–150

Stelljes, ME, 2005.  Mechanistic Hypothesis for n-Propylbromide and
Ramifications for Occupational Exposure Limit in the United States.
Technical Memorandum to EnviroTech International.  7 September, 2005.

Stump, 2005.  “The Reproductive Toxicity of nPB in Rats,”
Presentation by Dr Donald Stump at the North American Congress of
Clinical Toxicologists.  September 14, 2005.

Swanson, M.B., J.R. Geibig, and K.E. Kelly.  2002.  Alternative
Adhesives Technologies: Foam Furniture and Bedding Industries, Final
Draft.  Volume 2: Risk Screening and Comparison.  Chapter 4: Exposure
Assessment.  Produced by the University of Tennessee Center for Clean
Products and Clean Technologies under a grant from EPA’s Design for
the Environment Branch, Office of Pollution and Prevention and Toxics.
June 2002.  Available online at   HYPERLINK
"http://eerc.ra.utk.edu/ccpct/aap1.html"
http://eerc.ra.utk.edu/ccpct/aap1.html .

TERA, 2004.  Toxicological Excellence for Risk Assessment.  Scientific
Review of 1-Bromopropane Occupational Exposure Limit Derivations –
Preliminary Thoughts and Areas for Further Analysis.  2004.

Toraason, M., Lynch, D.W., DeBorda, D.G., Singh, N., Krieg, E., Butler,
M.A.,Toennis, C.A., Nemhauser, J.B., 2006. DNA damage in leukocytes of
workers occupationallyexposed to 1-bromopropane.  Mutation Research 603
(2006) 1–14

US EPA, 1991. Guidelines for Developmental Toxicity Risk Assessment.
U.S. Environmental Protection  Agency.  (A-2001-07, II-A-51)

US EPA, 1994a.  U.S. Environmental Protection Agency (US EPA).  1994.
Methods for derivation of inhalation reference concentrations and
application of inhalation dosimetry.  EPA/600/8-90/066F.  Office of
Health and Environmental Assessment, Washington, DC.  1994. (A-2001-07,
II-A-16)

US EPA, 1995a.  SCREEN3 air dispersion model. (A-2001-07, II-A-53)

US EPA, 1995b.  The Use of the Benchmark Dose Approach in Health Risk
Assessment. EPA/630-R-94-007.  Risk Assessment Forum, Washington, DC.
(A-2001-07, II-A-17)

US EPA, 1996.  Guidelines for Reproductive Toxicity Risk Assessment.
U.S. Environmental Protection Agency, Risk Assessment Forum, Washington,
DC, 630/R-96/009, 1996.

US EPA, 2003.    SEQ CHAPTER \h \r 1 Summary of Data on Workplace
Exposure to n-Propyl Bromide, May 21, 2003.  EPA’s summary of exposure
data from nPB suppliers and NIOSH.   (EPA-HQ-OAR-2002-0064-0015 and
EPA-HQ-OAR-2002-0064-0016).

Wang et al., 2003.   H. Wang, G. Ichihara, H. Ito, K. Kato, J. Kitoh, T.
Yamada, X. Yu, S. Tsuboi, Y. Moriyama, and Y. Takeuchi. 2003.
“Dose-Dependant Biochemical Changes in RateCentral Nervous System
after 12-Week Exposure to 1-Bromopropane”  NeuroToxicology 24: 199-206

Werner, 2003.  Comments from 3M on nPB proposed rule.
(EPA-HQ-OAR-2002-0064-58).

WIL, 2001.  WIL Research Laboratories. “An inhalation two-generation
reproductive toxicity study of 1-bromopropane in rats.” Sponsored by
the Brominated Solvent Consortium.  May 24, 2001. (II-D-10)

	Yamada T. et al., 2003.  Exposure to 1-Bromopropane Causes Ovarian
Dysfunction in Rats. Toxicol Sci 71:96-103 (A-2001-07, II-A-32)

Decisions for Each Sector or End Use

Amity International, 2001.    SEQ CHAPTER \h \r 1 Amity Product
Information Bulletin Sheet Ref. No. 00-003: Vapor Degreasing Good
Practice.  5 June 2001.  (A-2001-07, II-A-18)

Beck and Caravati, 2003.    Full citation above for “Human Health”
section.

Calhoun County, 2005.  Summary of Court Case against Franklin
Technologies and Mid-South Adhesive Company in Calhoun County, MS.

Collatz, 2003.  Comment entitled "Addition of n-Propyl-Bromide to the
Significant New Alternatives Policy (SNAP) List" submitted by Mark
Collatz, Director of Government Relations, The Adhesive and Sealant
Council, Inc.   04-Aug-2003. (EPA-HQ-OAR-2002-0064-0066)

Confidential submission, 1998.  Airborne Exposure Assessment of
1-Bromopropane, 1998.  (A-2001-07, II-D-89)

CSMA, 1999.  Comments from the Chemical Specialties Manufacturers
Association on Reconsideration of the 610 Nonessential Products Ban,
Docket A-98-31, IV-D-02. August 3, 1999.

Harper, 2005.    Full citation above for “Availability” section.

ICF, 2006a.  Full citation above for “Human Health” section.

Ichihara G. et al., 2002.   Full citation above for “Human Health”
section.

Kassem, 2003.  January 10, 2003 Letter from O. M. Kassem, Albemarle
Corporation to K. Bromberg, Small Business Administration Re: n propyl
bromine SNAP.  (A-2001-07, II-D-78)

Lake City Army Ammunition Plant, 2004.  March 9, 2004 Industrial Hygiene
Air Sampling Report for Normal Propyl Bromide Based Mouth Waterproofing
in Manufacture of 5.56 mm Ammunition.  S.A. Hawk.

Linnell, 2003.  Comments from the Electronics Industry Alliance.
(IV-D-25/EPA-HQ-OAR-2002-0064 items -0043, -0044, and -0045)

Majersik et al., 2004.  Full citation above for “Human Health”
section.

Majersik et al, 2005.   Full citation above for “Human Health”
section.

Miller, 2005.   Full citation above for “Human Health” section.

NIOSH, 1999.  U.S. Dept. of Health and Human Services, Letter to Custom
Products Inc., December 1, 1999.  Re: results of Dec. 1998 survey of
workplace exposure to nPB at Custom Products. (HHE Report 98-0153)
(A-2001-07, II-D-6)

NIOSH, 2000a.  U.S. Dept. of Health and Human Services, Letter to Marx
Industries, Inc., February 1, 2000.  Re: results of nPB exposure
assessment survey conducted Nov. 16-17, 1999. (A-2001-07, II-D-7)

NIOSH, 2000b.  U.S. Dept. of Health and Human Services, Letter to Custom
Products Inc., December 21, 2000.  Re: results of nPB exposure
assessment survey conducted Nov. 16, 2000.  (HHE Report 98-0153)
(A-2001-07, II-D-8)

NIOSH, 2001.  U.S. Dept. of Health and Human Services, Letter to STN
Cushion Company, March 7, 2001.   Re: Results of nPB exposure assessment
survey conducted November 14, 2000. (A-2001-07, II-D-9)

NIOSH, 2002a.  NIOSH Health Hazard Evaluation Report: HETA #
98-0153-2883; Custom Products, Inc.; Mooresville, NC.  National
Institute for Occupational Safety and Health.  November 2002.  Available
online at   HYPERLINK
"http://www.cdc.gov/niosh/hhe/reports/pdfs/1998-0153-2883.pdf"
http://www.cdc.gov/niosh/hhe/reports/pdfs/1998-0153-2883.pdf .

NIOSH, 2002b.  NIOSH Health Hazard Evaluation Report: HETA
#2000-0410-2891; STN Cushion Company; Thomasville, NC.  National
Institute for Occupational Safety and Health.  August 2002.  Available
online at   HYPERLINK
"http://www.cdc.gov/niosh/hhe/reports/pdfs/2000-0410-2891.pdf"
http://www.cdc.gov/niosh/hhe/reports/pdfs/2000-0410-2891.pdf .
(A-2001-07, II-A-31)

NIOSH, 2003a.  NIOSH Health Hazard Evaluation Report #99-0260-2906  Marx
Industries, Inc. Sawmills, NC  Available online at   HYPERLINK
"http://www.cdc.gov/niosh/hhe/reports/pdfs/1999-0260-2906.pdf"
http://www.cdc.gov/niosh/hhe/reports/pdfs/1999-0260-2906.pdf .

Raymond and Ford, 2005.   Full citation above for “Human Health”
section.

US EPA, 2003.  Summary of Data on Workplace Exposure to n-Propyl
Bromide, May 21, 2003.  EPA’s summary of exposure data from nPB
suppliers and NIOSH. (EPA-HQ-OAR-2002-0064-0015 and -0016)

US EPA, 2004.  US EPA Solvent Market Report:  The U.S. Solvent Cleaning
Industry and the Transition to Non Ozone Depleting Substances.  Prepared
for U.S. Environmental Protection Agency, Significant New Alternatives
Policy (SNAP) Program by ICF Consulting.  September 2004.

Werner, 2003.  Full citation above for “Human Health” section.

Williams, 2005.   Full citation above for “Availability” section.

How did EPA choose the use conditions in the alternate proposal?

Ensolv, 2006.  Material Safety Data Sheet for Ensolv Solvents.  Enviro
Tech International.  February, 2006.

ERG, 2004.  Analysis of Health and Environmental Impacts of ODS
Substitutes—Evaluating the need to set a short-term exposure or
ceiling limit for n-propyl bromide.  ERG.  June 8, 2004.

NIOSH, 2003b.  Method 1025 for 1- and 2-Bromopropane.  NIOSH Manual of
Analytical Methods, 4th Edition, March 15, 2003.

NIOSH, 2003c.  Method 1003 for Halogenated Hydrocarbons.  NIOSH Manual
of Analytical Methods, 4th Edition, March 15, 2003.

What other options did EPA consider?

CSMA, 1999.   Full citation above for “Decisions for Each Sector and
End Use” section.

ICF, 2006a.   Full citation above for “Human Health” section.

Lake City Army Ammunition Plant, 2004.   Full citation above for
“Decisions for Each Sector and End Use” section

Linnell, 2003.   Full citation above for “Ozone Depletion Potential
and Other Environmental Impacts” section.

Kassem, 2003.   Full citation above for “Decisions for Each Sector and
End Use” section.

NIOSH, 1999.    SEQ CHAPTER \h \r 1 Letter from Dept. of Health and
Human Services to Marx Industries, Inc., February 1, 2000.  Re: results
of nPB exposure assessment survey conducted Nov. 16-17, 1999.
(A-2001-07, II-D-6)

NIOSH, 2000a.  U.S. Dept. of Health and Human Services, Letter to Marx
Industries, Inc., February 1, 2000.  Re: results of nPB exposure
assessment survey conducted Nov. 16-17, 1999. (A-2001-07, II-D-7)

NIOSH, 2002a.  NIOSH Health Hazard Evaluation Report: HETA #
98-0153-2883; Custom Products, Inc.; Mooresville, NC.  National
Institute for Occupational Safety and Health.  November 2002.  Available
online at   HYPERLINK
"http://www.cdc.gov/niosh/hhe/reports/pdfs/1998-0153-2883.pdf"
http://www.cdc.gov/niosh/hhe/reports/pdfs/1998-0153-2883.pdf .

NIOSH.  2002b.  NIOSH Health Hazard Evaluation Report: HETA
#2000-0410-2891; STN Cushion Company; Thomasville, NC.  National
Institute for Occupational Safety and Health.  August 2002.  Available
online at   HYPERLINK
"http://www.cdc.gov/niosh/hhe/reports/pdfs/2000-0410-2891.pdf"
http://www.cdc.gov/niosh/hhe/reports/pdfs/2000-0410-2891.pdf .
(A-2001-07, II-A-31)

NIOSH, 2003a.  NIOSH Health Hazard Evaluation Report #99-0260-2906  Marx
Industries, Inc. Sawmills, NC  Available online at   HYPERLINK
"http://www.cdc.gov/niosh/hhe/reports/pdfs/1999-0260-2906.pdf"
http://www.cdc.gov/niosh/hhe/reports/pdfs/1999-0260-2906.pdf .

US EPA, 2003.  Full citation above for “Decisions for Each Sector or
End Use” section.

Williams, 2005.  Full citation above for “Availability” section.

What are the anticipated costs of this regulation to the regulated
community?

Kassem, 2003.  Full citation above for “Decisions for Each Sector and
End Use” section.

Tattersall, 2004.  Conversation between M. Sheppard, EPA, and Tom
Tattersall, MicroCare Corp.

Ultronix, 2001.  Response to questionnaire from EPA by C. Wolf,
Ultronix, 2001. (A-2001-07, II-D-76)

US EPA, 2003.   Full citation above for “Human Health” section.

US EPA, 2006.  Analysis of Economic Impacts of nPB Rulemaking.  2006.

Comparison of EPA’s June 2003 Proposal and This Proposal

ACGIH, 2005.  Full citation above for “Human Health” section.

CERHR, 2002a.  Full citation above for “Human Health” section.

CERHR, 2002b.   Full citation above for “Human Health” section.

Doull and Rozman, 2001.  Derivation of an Occupational Exposure Limit
for n-Propyl Bromide, prepared by John Doull, Ph.D., M.D., and Karl K.
Rozman, Ph.D., D.A.B.T. submitted by Envirotech International, Inc.
(A-2001-07, II-D-14)

ICF, 2001. Brief Discussion of the BMD Approach: Overview of its
Purpose, Methods, Advantages, and Disadvantages. Prepared for U.S. EPA.
(A-2001-07, II-A-52)

Full citation above for “Human Health” section.

ICF, 2002b. Comments on the NTP- Center for the Evaluation of Risks to
Human Reproduction, Final Report on 1-Bromopropane.  Cover Letter Dated
5/9/02.  (EPA-HQ-OAR-2002-0064-0013)

ICF, 2004g. Expert Panel Response on nPB AEL, Prepared for U.S. EPA,
December, 2004

ICF, 2004h. nPB Human Relevance, Prepared for U.S. EPA, September, 2004

ICF, 2006a.  Full citation above for “Human Health” section.

Rodricks, 2002.   Full citation above for “Human Health” section.

Rozman and Doull, 2002.   Full citation above for “Human Health”
section.

Rozman and Doull, 2005.  Full citation above for “Human Health”
section.

SLR International, 2001.  Full citation above for “Human Health”
section.

Stelljes and Wood, 2004.   Full citation above for “Human Health”
section.

Stelljes, ME.  2005.   Full citation above for “Human Health”
section.

TERA, 2004.   Full citation above for “Human Health” section.

How can I use nPB as safely as possible?

ACGIH, 2002.  Industrial Ventilation: A Manual of Recommended Practice
23rd Edition.  American Conference of Governmental Industrial
Hygienists, Cincinnati, Ohio  Available online at www.acgih.org.

List of Subjects in 40 CFR Part 82

Environmental protection, Administrative practice and procedure, Air
pollution control, Reporting and recordkeeping requirements.

Protection of Stratospheric Ozone:  Listing of Substitutes for
Ozone-Depleting

Substances–n-Propyl Bromide

Notice of Proposed Rulemaking

 of   PAGEREF End_of_document \h  142  pages

Dated:  _____________________________________________

___________________________________________________

Stephen L. Johnson, Administrator

For the reasons set out in the preamble, 40 CFR part 82 is proposed to
be amended as follows:

PART 82 - PROTECTION OF STRATOSPHERIC OZONE

1.	The authority citation for Part 82 continues to read as follows:

Authority:  42 U.S.C. 7414, 7601, 7671 - 7671q.

2.	Subpart G is amended by adding Appendix Q to read as follows:

Subpart G - Significant New Alternatives Policy Program

*****

Appendix Q to Subpart G - Substitutes Subject to Use Restrictions and
Unacceptable Substitutes

Listed in the [publication date of final rule] final rule.

AEROSOLS

UNACCEPTABLE SUBSTITUTES

End Use	Substitute	Decision	Further Information

Aerosol solvents	n-propyl bromide (nPB) as a substitute for CFC-113,
HCFC-141b, and methyl chloroform	Unacceptable 	EPA finds unacceptable
risks to human health in this end use compared to other available
alternatives.  nPB, also known as 1-bromopropane, is Number 106-94-5 in
the CAS Registry.

ADHESIVES, COATINGS, AND INKS

SUBSTITUTES THAT ARE ACCEPTABLE SUBJECT TO USE CONDITIONS

End Use	Substitute	Decision	Use Conditions	Further Information

Coatings	n-propyl bromide (nPB) as a substitute for methyl chloroform,
CFC-113, and HCFC-141b	Acceptable subject to use conditions	Use is
limited to coatings at facilities that have provided EPA information
demonstrating their ability to meet the recommended workplace exposure
limit as of [INSERT DATE OF PUBLICATION].	EPA expects that all users of
nPB will adhere to a voluntary acceptable exposure limit of 17 ppm on an
8-hour time-weighted average and would comply with any final Permissible
Exposure Limit that the Occupational Safety and Health Administration
issues in the future under 42 U.S.C. 7610(a).

nPB, also known as 1-brompropane, is Number 106-94-5 in the CAS
Registry.

Note 1 : In accordance with the limitations provided in Section 310(a)
of the Clean Air Act (42 U.S.C. 7610(a)), nothing in this table shall
affect the Occupational Safety and Health Administrations’ authority
to promulgate and enforce standards and other requirements under the
Occupational Safety and Health Act of 1970 (29 U.S.C. 651 et seq.)

Note 2:  As of [INSERT DATE OF PUBLICATION], the Lake City Army
Ammunition Plant is the only facility that has provided information to
EPA demonstrating the facility's ability to meet the recommended
workplace exposure limit when using nPB in coatings.

ADHESIVES, COATINGS, AND INKS

UNACCEPTABLE SUBSTITUTES

End Use	Substitute	Decision	Further Information

Adhesives	n-propyl bromide (nPB) as a substitute for CFC-113, HCFC-141b,
and methyl chloroform	Unacceptable	EPA finds unacceptable risks to human
health in this end use compared to other available alternatives.  nPB,
also known as 1-bromopropane, is Number 106-94-5 in the CAS Registry.

BILLING CODE 6560-50-P

  CFC-113 is also referred to as Freon-113, or
1,1,2-trifluoro-1,2,2-trichloroethane.  Its CAS Reg. No. is 76-13-1.

 Methyl chloroform is also referred to as 1,1,1-trichloroethane, TCA,
MCF, or 1,1,1.  Its CAS Reg. No. is 71-55-6.

 HCFC-141b is also referred to as 1,1-dichloro-1-fluoroethane.  Its CAS
Reg. No. is 1717-00-6.

 See 29 CFR 1910.1052(d)(4)(i).

 Also called trichlorethene or TCE, C2Cl3H, CAS Reg. No. 79-01-6.

 Also called PERC, tetrachloroethylene, or tetrachloroethene, C2Cl4, CAS
Reg. No. 127-18-4.

 nPB emissions in the tropics would have an ODP of 0.071 to 0.100; the
portions of the U.S. outside the continental U.S., such as Alaska,
Hawaii, Guam, and the U.S. Virgin Islands, contain less than 1 percent
of the U.S.’s businesses in industries that could use nPB.  Thus,
their potential impact on the ozone layer must be significantly less
than that of the already low impact from nPB emissions in the
continental U.S.  (U.S. Economic Census, 2002a through f)

ß

÷

,

-

-

.

਀ద

&

&

&

@

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

̀Ĥ☊ଌF愀Ĥ

kdC

☊ଌF㜀Ĥ␸䠁Ĥ

&

&

&

kd½

☊

&

&

&

&

&

&

\

&

\

&

&

&

&

&

&

ༀ㢄帄㢄愄Ĥ[਀&䘋

h®

&

Æ

ß

à

%

'

Ž

Å

Æ

h®

h®

&

&

Æ

&

@

&

Æ

&

Æ

&

@

&

Æ

&

Æ

&

@

&

Æ

&

Æ

&

@

&

@

h®

h®

@

K਀&䘋

h®

h®

K਀&䘋

K਀&䘋

K਀&䘋

K਀&䘋

@

@

@

@

Ā"

&

@

将

鈆

&

@

&

@

&

@

&

@

将

鈆

&

@

&

@

将

鈆

&

@

将

鈆

&

@

将

鈆

&

@

将

鈆

&

@

将

鈆

u

옍#

hÑ

옍#

옍#

옍#

h®

hÑ

@

@

h®

h®

h®

@

@

@

@

@

&

&

&

@

&

@

&

@

&

&

&

&

&

&

@

&

@

’z’¸ ç¥

&

&

h®

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

&

¶

&

¶

&

¶

&

¶

¶

&

¶

&

¶

¶

&

&

¶

&

¶

&

¶

&

¶

&

¶

&

¶

&

@

&

@

&

@

&

@

&

@

h®

&

&

@

&

@

@

&

¶

&

&

&

&

&

☊

\

\

&

&

&

&

&

&

&

&

&

&

ô

ô

on between two compounds with different WELs does not necessarily mean
that using a compound with a lower WEL is more risky.  Risks from
exposure will also vary due to emission controls in place, work
practices, ventilation, rate of spraying, and vapor pressure of the
solvent.

 iPB is also referred to as 2-bromopropane, 2-propyl bromide, or 2-BP.
Its CAS registry number is 75-26-3.

 The estrous cycle fulfills the same role in reproduction as the
menstrual cycle in women.

 In addition, significant changes in the distribution of ovarian cell
types were seen in the high dose groups (750 ppm) but were not counted
in lower dose groups.

 Benchmark dose analysis uses mathematical models to fit dose-response
data and identifies the “benchmark dose” associated with a
“benchmark response” determined to be significant – see EPA’s
Risk Assessment Forum Guidelines for Benchmark Dose Modeling (EPA,
2000a) and 68 FR 33292-33293 in the June NPRM on how EPA uses benchmark
dose modeling in setting an exposure limit.

 In this analysis, the benchmark response was a 10% reduction in the
mean number of estrous cycles, consistent with EPA guidance (EPA,
2000a).  The BMDL for the same endpoint using a response of one standard
deviation would be slightly higher, at 208 ppm.

 Pharmacodynamics refers to the biochemical and physiological effects of
chemicals in the body and the mechanism of their actions.

 Pharmacokinetics refers to the activity or fate of chemicals in the
body, including the processes of absorption, distribution, localization
in tissues, biotransformation, and excretion.

 The blood/air partition coefficient is the ratio of a chemical’s
concentration between blood and air when at equilibrium.

	7 Smog, also known as ground-level ozone, is produced from emissions of
volatile organic compounds that react under certain conditions of
temperature and light.

 Unlike samples measured directly in the breathing zone, area samples
measured in the study are not considered representative of actual
exposure and are not discussed here.  Short-term measurements taken over
15 minutes from personal samplers, although in some cases extremely
high, are not discussed in detail here because available toxicity
information does not indicate need for a short-term exposure limit in
addition to the 8-hr TWA limit (ACGIH, 2005; ERG, 2004; see section
IV.A.5).  Additional information on these other samples is in the
occupational exposure assessment for aerosols in the risk screen for nPB
(ICF, 2006a).

 This corresponds roughly to a regional or room fan at low levels or
natural air currents in an open area.  Confined areas would have even
lower air exchange rates with higher exposure levels.

  We consider use of 1000 g/day to be the high end of typical use, based
on the setup of one of the exposure studies (Confidential Submission,
1998).  The typical aerosol solvent user in the electronics industry
uses a can per day (Williams, 2005).  This is comparable to or slightly
less than the spray rate assumed in the modeling.

 In its methylene chloride standard, OSHA defined representative
sampling as follows:  “The employer has taken one or more personal
breathing zone air samples for at least one employee in each job
classification in a work area during every work shift, and the employee
sampled is expected to have the highest…exposure.”   (29 CFR
1910.1052(d)(1)(ii)(A)).

 The action level is the exposure level that is  half the 8-hour TWA
exposure limit.  In this case, the action level would be 8.5 ppm.

  PAGE   33

  PAGE   60

  PAGE   98

  PAGE   109

  PAGE   111

  PAGE   141