standard deviations. Two sets of WPF results were determined: One for
the 3M 2040 filter and a second for the 3M 7255. A total of 140 samples
were collected--one sample was eliminated due to low mass loading, 10
samples were lost due to equipment problems, and 85 samples had inside-
sample mass values that were non-detectable. Of the remaining 44
samples, one outlier was identified in the electret filter data set,
leaving 22 sets for the 3M 2040 filter and 21 sets for the 3M 7255
filter. No field blank adjustments were reported (i.e., no lead was
detected on the field blanks). The authors reported a mean WPF of 562
and a 5th percentile of 71 for the 3M 2040 filter-respirator
combination, and a mean WPF of 1006 and a 5th percentile of 80 for the
3M 7255 filter-respirator combination.
    When no lead was detected for the inside samples, the WPF results
were recalculated using the detection limit to represent the mass for
these samples. From these recalculations, the authors identified one
outlier in the electret filter data set and two outliers in the
mechanical filter data set. They then calculated geometric means,
geometric standard deviations, and 5th percentile WPFs for the 67
samples for the 3M 2040 filter and for the 59 samples for the 3M 7255
filter. The authors reported a mean WPF of 420 and a 5th percentile of
101 for the 3M 2040 filter-respirator combination, and a mean WPF of
549 and a 5th percentile of 138 for the 3M 7255 filter-respirator
combination.
    The authors concluded that the performance differences between the
two filter types were not statistically significant. Both filters
provided 5th percentile protection factors above 10. No WPFs were less
than 30. Under these workplace conditions, no difference was found in
the level of protection provided by the electrostatic HEPA filter
compared to a mechanical HEPA filter.
    Colton and Bidwell study (Ex. 9-16). C. Colton and J. Bidwell of 3M
presented a research paper at the May 1999 AIHCE on a WPF study they
performed in a battery manufacturing plant with workers using three
NIOSH-approved filtering facepiece respirators. The filtering facepiece
respirators tested were the 3M 8210 and 3M 8511, approved by NIOSH
under the 42 CFR 84 respirator certification standards, and the 3M 8710
filtering facepiece, approved by NIOSH under the 30 CFR 11 respirator
certification standards. The authors measured lead exposures for 21
workers in the battery-manufacturing and assembly areas of the plant.
The worker job classifications tested were stackers, heat sealers,
burners, and assemblers. The workers were informed of the purpose and
procedures of, and their role in, the study, and were provided with
instructions on proper donning, fitting, and user seal check
procedures, as well as respirator operation. In addition, the workers
had to pass a Bitrex[supreg] qualitative fit test with all three
respirators, and they had to be clean shaven. They were observed in the
workplace by the authors on a one-on-one basis throughout the sampling
periods.
    The sampling probe was a Liu probe that was inserted opposite the
mouth near the midline of the respirator. It projected one centimeter
into the facepiece. The sampling cassette was attached directly to the
probe, and a cassette heater was used to prevent condensation of
moisture from exhaled breath. Inside and outside samples were collected
at a flow rate of two liters per minute for 79 to 159 minutes. Three
samples were collected per day for each worker. Field blanks were used,
and care was taken to avoid handling contamination.
    The inside samples were analyzed for lead using PIXEA. Outside
samples were analyzed by ICP spectroscopy. The authors presented the
range of outside and inside sample lead concentrations, and the
associated geometric means and standard deviations for each respirator
model tested. Three sets of WPF results were determined: One for the 3M
8710, a second for the 3M 8210, and a third for the 3M 8511. Lead was
not detected on five of the inside samples for the 3M 8710, 19 for the
3M 8210, and 23 for the 3M 8511. No field blank adjustments were
reported (i.e., no lead was detected on the field blanks). The authors
reported a mean WPF of 730, with a 5th percentile of 105, for the 3M
8710 respirator; a mean WPF of 955, with a 5th percentile of 73, for
the 3M 8210; and a mean WPF of 673, with a 5th percentile WPF of 169,
for the 3M 8511 using test samples with detectable lead levels. When no
lead was detected on the inside samples, the WPF results were
calculated by using 70% of the limit of detection as the mass for
inside samples. The authors reported a mean WPF of 804, with a 5th
percentile of 111, for the 3M 8710 respirator; a mean WPF of 2210, with
a 5th percentile of 133, for the 3M 8210; and a mean WPF

of 1970, with a 5th percentile WPF of 223, for the 3M 8511.
    The authors stated, ``All respirator models provided an equivalent
level of protection,'' and that ``[a]ll the respirators tested reliably
provided workplace protection factors of 10 when properly fitted, worn,
and used.'' No reported WPFs were less than 51, and no difference in
workplace protection was found between workers using 30 CFR part 11-
approved respirators and workers using 42 CFR 84-approved respirators.
The authors concluded that, using the 5th percentile WPFs as an
indicator of performance, the APFs should not differ between these
respirators.
2. Additional Studies Not Used in the Updated Analyses
    The Agency received a number of comments on the relationship
between fit testing and APFs. OSHA regulations require that when a
respirator user cannot pass a fit test with a particular respirator
model, it cannot be used. OSHA does not believe that it is appropriate
to assign a lower protection factor to a respirator (e.g., half the
APF) when the respirator doesn't fit. However, a number of fit test
studies, and one study on farm worker exposures to bioaerosols, were
submitted to the record for the Agency to evaluate in terms of APFs.
OSHA has evaluated these studies and determined that they do not meet
the criteria that data must meet to be included in the database. These
criteria have been described above.
    NIOSH agreed (Tr. at 102) that the APF values resulting from OSHA's
multifaceted approach provide reasonable values for the level of
protection expected for each respirator class. Proposed Table 1
(``Assigned Protection Factors'') represents the state of the art for
each class or respirator. However, NIOSH stated that designating a
specific APF for a respirator class will not ensure that a respirator
will perform as expected. The protection afforded by a respirator is
contingent on: The respirator user adhering to the respirator program
requirements of OSHA's Respiratory Protection Standard; the use of
NIOSH-certified respirators in their approved configuration; and fit
testing for each employee that ensures selection of a properly fitting
respirator. The following studies, which OSHA did not include in its
updated analyses, typically violated one or more of these three
conditions.
    Don-Hee Han study (Ex. 9-13-2). NIOSH (Ex. 9-13) submitted a study
by Don-Hee Han (Ex. 9-13-2) of the 3M 8511 cup-shaped filtering
facepiece, the MSA Affinity foldable FR 200, and the Willson N95 10FL
produced by Dalloz Safety in response to OSHA's request in the NPRM for
additional studies that may be useful in determining APFs. The author
of the study permitted workers who did not pass a fit test with a
minimum fit factor of 100, as required by OSHA's Respiratory Protection
Standard, to participate in the study. OSHA reviewed this study and did
not add the data set to its quantitative analyses because it was a PPF
study that is not directly comparable with WFP studies used by OSHA in
its APF determinations. However, the study results confirmed that when
a worker's filtering facepiece respirator is fit tested properly, it is
capable of achieving a protection factor of at least 10.
    Peacock study (Ex. 9-13-4). This fit test research report was
submitted to the record by NIOSH. In this study, a liquid-aerosol QNFT
(Large Particle QNFT (LPQNFT)) was developed and used to evaluate
filter penetration of a regular N95 respirator. Protection factors
determined by the LPQNFT were compared to fit factors obtained using
the saccharin QLFT. The sensitivity and specificity of the saccharin
QLFT were evaluated. The results for the specifity of the LPQNFT
indicated that workers who failed the saccharin QLFT also failed the
LPQNFT when using a protection factor >= 100. The sensitivity was low.
Twelve (12) subjects passed both the LPQNFT and the saccharin QLFT (out
of 28 subjects), but another 16 subjects failed the saccharin test
while passing the LPQNFT. Peacock concluded that the LPQNFT may be
subject to particle deposition at leakage sites, as well as conditions
inside the facepiece that would lead to sampling bias. OSHA did not
rely on these fit test data for setting APFs because, as Peacock noted,
further studies should be conducted to identify the cause of these
problems.
    Lee and Nicas study (Ex. 17-7-3). NIOSH submitted this study of N95
respirators used against Mycobacterium tuberculosis (TB). In this
study, Lee and Nicas (Ex. 17-7-3) computed risks of TB infection using
five medium- or regular-size N95 filtering facepiece respirators. Five
NIOSH-approved respirators were selected for evaluation after reviewing
manufacturer-provided fit test, comfort, and cost data. After extensive
evaluation, the original five brands were rank ordered from highest to
lowest fit test pass rates, and the authors calculated the risk of TB
transmission. The authors concluded that fit testing is necessary to
ensure that respirators perform as expected. However, OSHA did not
accept this study for its APF analyses because it is not a WPF or SWPF
study, and addresses only fit testing issues.
    Coffey, et al. study (Ex. 17-7-4). NIOSH submitted to the record a
publication by Coffey et al. (Ex. 17-7-4). In this study, 18 N95
filtering facepiece respirators were evaluated. The authors determined
the following measurements from the results: 5th percentile SWPF value;
the average SWPF per shift; the h-value; and the assignment error. A
SWPF test was used to determine respirator performance, which was
assessed using a Portacount Plus with test subjects performing six
standard fit test exercises. However, the generally accepted format for
a SWPF study involves test subjects performing simulated workplace
exercises (e.g., shoveling pebbles, moving blocks, pounding nails).
    Using this procedure, the authors found that when properly fit
tested, over 80% of the poorly performing respirators achieved a
protection factor of more than 10. However, OSHA did not use this study
in its APF determinations since this was not a WPF or SWPF study.
Nevertheless, the study supports the requirement that APFs apply only
when used within the context of a comprehensive respirator program.
    Reponen et al. study (Exs. 19-8-3 and 19-8-4). The purpose of this
study was to further develop a prototype personal-sampling system for
use with N95 filtering facepiece respirators. The study results were
calculated from 30-60 minute Co and Ci measurements taken across
multiple agricultural settings, tasks, and simulated exposures. The
data were combined to calculate dust, microorganism, and cultured
microorganism exposures. Descriptions of tasks in several workplaces
were provided.
    The N95 respirators in this study performed at or above a WPF of 10
when evaluated using dust measurements. However, the dust-exposure
measurements counted both dust particles and microorganisms because the
optical-particle counter used for this purpose does not differentiate
between organic and nonorganic particles. When they calculated WPFs for
the microorganism samples alone, the WPFs decreased somewhat. The
authors concluded that the geometric mean WPF increased with increasing
particle size, and that the WPFs were smaller for biological particles
than for dust. The authors speculated that differences in WPFs may
result from the measurement effects of particle size or density. They
also said that even a small variation in the

density of particles can have a pronounced effect on the loss of dust
particles through faceseal leaks due to impaction. The authors
concluded that their findings deserve further research.
    OSHA agrees with the authors that further research is needed to
substantiate and explore these findings. Also, the Agency has
significant concern regarding the measurement methodology used in this
prototype study. For example, it is not clear whether the WPF
differences are valid or are simply the result of using different
measurement methods. Therefore, the Agency decided not to use this
study for developing APFs.
    Summary and conclusions for studies not used in the updated
database. OSHA reviewed the studies submitted to the APF rulemaking
docket and determined that five of them were unsuitable for the
database used to develop APFs. OSHA established a set of criteria in
the proposal for evaluating new studies for inclusion in the APF
database. The studies by Han (Ex. 9-13-4), Peacock (Ex. 9-13-4), Lee
and Nicas (Ex. 17-7-3), Coffey et al. (Ex 17-7-4), and Reponen et al.
(Exs. 19-8-3 and 19-8-4) were not used by OSHA in setting the final
APFs because these studies did not follow established WPF or SWPF
protocols, or required further research to substantiate or explore the
results.

IV. Health Effects

    American workers use respirators as a means of protection against a
multitude of respiratory hazards that include chemical, biological, and
radiological agents. Respirators provide protection from hazards that
are immediately life-threatening, as well as hazards associated with
routine operations for which engineering controls and work practices do
not protect employees sufficiently. When respirators fail, or do not
provide the degree of protection expected by the user, the user is
placed at an increased risk of adverse health effects that result from
exposure to the respiratory hazards present. Therefore, it is critical
that respirators perform properly to ensure that users are not at an
increased risk of experiencing adverse effects caused by exposure to
respiratory hazards.
    In this final rulemaking, OSHA defined the minimal level of
protection a respirator is expected to achieve (i.e., the APFs in Table
1), as well as the MUCs for the respirators. The Agency also is
superseding most of the existing APF table requirements in its
substance-specific standards. By superceding the APF tables, the Agency
estimates that the benefits for the final APFs under the Respiratory
Protection Standard will be available as well to employers who must
select respirators for employee use under the substance-specific
standards. In addition, the Agency believes that harmonizing the APFs
of the substance-specific standards with the APFs in the Respiratory
Protection Standard will reduce confusion among the regulated community
and aids in uniform application of APFs, while maintaining employee
protection at levels at least as protective as the existing APF
requirements.

V. Summary of the Final Economic Analysis and Regulatory Flexibility
Analysis

A. Introduction

    OSHA's Final Economic and Regulatory Flexibility Screening Analysis
(FEA) addresses issues related to the costs, benefits, technological
and economic feasibility, and economic impacts (including small
business impacts) of the Agency's Assigned Protection Factors (APF)
rule. The Agency has determined that this rule is not an economically
significant rule under Executive Order 12866. The economic analysis
meets the requirements of both Executive Order 12866 and the Regulatory
Flexibility Act (RFA; as amended in 1996). The FEA presents OSHA's full
economic analysis and methodology. The Agency entered the complete FEA
into the docket as Exhibit 11. The remainder of this section summarizes
the results of that analysis.
    The purpose of this FEA is to:
     Evaluate the costs employers would incur to meet the
requirements of the APF rule;
     Estimate the benefits of the rule;
     Assess the economic feasibility of the rule for affected
industries; and
     Determine the impacts of the rule on small entities and
the need for a Regulatory Flexibility Analysis.

B. The Rule and Affected Respirator Users

    OSHA's APF rule would amend 29 CFR 1910.134(d)(3)(i)(A) of the
Respiratory Protection Standard by specifying a set of APFs for each
class of respirators. These APFs specify the highest multiple of a
contaminant's permissible exposure limit (PEL) at which an employee can
use a respirator safely. The APFs would apply to respirator use for
protection against overexposure to any substance regulated under 29 CFR
1910.1000. In addition, OSHA rules for specific substances under
subpart Z (regulated under the authority of section 6(b)(5) of the OSH
Act of 1970, 29 U.S.C. 655) specify APFs for respirators used for
protection against these chemicals (hereafter referred to as Sec.
6(b)(5) substances). The rule would supercede most of these protection
factors, and harmonize APFs for these substances with those for general
respirator use.
    OSHA based estimates of the number of employees using respirators
and the corresponding number of respirator-using establishments on the
NIOSH-BLS survey of respirator use and practices \2\ (Ex. 6-3). The
NIOSH-BLS survey provides up-to-date use estimates by two-digit
industry sector and respirator type for establishments in which
employees used respirators during the previous 12 months.\3\ As shown
in Table V-1, an estimated 291,085 establishments reported respirator
use in industries covered by OSHA's regulation. Most of these
establishments (208,528 or 71.6 percent) reported use of filtering
facepieces. Substantial percentages of establishments also reported the
use of half-mask and full facepiece non-powered air-purifying
respirators (49.0 and 21.4 percent, respectively). A smaller number of
establishments reported use of powered air-purifying respirators
(PAPRs) and supplied-air respirators (SARs). Fifteen percent of
establishments with respirators (43,154) reported using PAPRs and 19
percent (56,022) reported using SARs. Table V-2 presents estimates of
the number of respirator users by two-digit industry sector. An
estimated 2.3 million employees used filtering facepiece respirators in
the last 12 months, while 1.5 million used half masks, and 0.7 million
used full facepiece non-powered air-purifying respirators. Fewer
employees reported using PAPRs (0.3 million) and SARs (0.4 million).
The industry-specific estimates show substantial respirator use in
several industries, including the construction sector, several
manufacturing industries (SICs 28, 33, 34, and 37), and Health services
(SIC 80).
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    \2\ Preliminary results from the 2001 NIOSH-BLS ``Survey of
Respirator Use and Practices'' in press. NIOSH commissioned the
survey to be conducted by BLS, who also tabulated the data after
completing the survey.
    \3\ The survey was conducted between August 2001 and January
2002. It asked: ``During the past 12 months, how many of your
current employees used respirators at your establishment?'' It
excluded voluntary use of respirators from detailed followup
respirator use questions (Ex. 6-3).

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BILLING CODE 4510-26-C

    The standard would have different impacts on employers using
respirators to comply with OSHA substance-specific standards than for
employers using respirators for other purposes. Therefore, OSHA used
findings from the NIOSH-BLS survey of establishments that reported
respirator use, by general respirator class, for protection against
specific substances (see Table V-3). OSHA applied these numbers to all
respirator users and establishments within the industries that make up
each sector to derive substance-specific estimates of respirator use.
For those Sec.  6(b)(5) substances not reported by NIOSH, OSHA used
expert judgments of a consultant with experience in the respirator
industry to estimate the percentage of establishments and employees
that use respirators for protection against these chemicals (Ex. 6-2)
(see Table V-3).

C. Compliance Costs

    The standard does not raise issues of technological feasibility
because it requires only that employers use respirators already on the
market. Further, these respirators are already in use and have proven
feasible in a wide variety of industrial settings. However, costs for
the APF standard result from requiring some users to switch to more
protective respirators than they currently use. When the APF is lower
than the baseline (current) APF, respirator users must upgrade to a
more protective model. Both the 1992 ANSI Z88.2 Respiratory Protection
Standard and the 1987 NIOSH RDL specify APFs for certain classes of
respirators. The Agency assumed that employers currently use the ANSI
or NIOSH APFs, or the APFs in the OSHA substance-specific standards, as
applicable, to select respirators. While the Agency currently refers to
the NIOSH RDL as its primary reference for APFs, in the absence of an
applicable OSHA standard, this analysis assumes that, in most cases,
adhering to the existing ANSI APFs fulfills employers' legal obligation
for proper respirator selection under the existing Respiratory
Protection Standard. However, in the case of full facepiece negative
pressure respirators, the Agency has established that an APF of 50, as
opposed to ANSI's APF of 100, is currently acceptable. In this regard,
all but one of the substance-specific standards with APFs for full
facepiece negative pressure respirators set an APF of 50. In addition,
the existing respirator rule and its supporting preamble require that
quantitative fit testing of full facepiece negative pressure
respirators must achieve a fit factor of 500 when employees use them in
atmospheres in excess of 10 times the PEL; this requirement assumes a
safety factor of 10. Therefore, based on a fit factor of 500, such
respirators are safe to wear in atmospheres up to 50 times the PEL,
consistent with similar requirements regarding respirator use found in
existing standards for Sec.  6(b)(5) chemicals.
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BILLING CODE 4510-26-C
    For each respirator type, OSHA compared the new and existing
standards and, where these new APFs were lower, identified an
incrementally more protective respirator model. To be adequate, the
more protective respirator must have an APF greater than the current
APF.
1. Number of Users Required To Upgrade Respirator Models
    For a given respirator type, the number of users required to shift
to a more protective respirator depends on two factors: the total
number of users of that type, and the percentage of those users for
whom the ambient exposure level is greater than the APF. While survey
data are available to estimate the number of users, virtually no
information is available in the literature that provides a basis for
estimating the percentage of users required to upgrade respirators. The
percentage of workers switching respirators would depend on the profile
or frequency distribution of users' exposure to contaminants relative
to the PEL. For example, the Agency is lowering the APFs for full
facepiece respirators used to protect against cotton dust from 100 to
50; accordingly, when workers have ambient exposures that are greater
than 50 times the PEL, employers must upgrade the respirator from a
full facepiece negative pressure respirator to a more protective
respirator (e.g., a PAPR).
    Because of the absence of data on this issue, OSHA made several
assumptions regarding the requirement to upgrade respirators. First,
OSHA assumed that employers use respirators only when their employees
have exposures above the PEL. Second, OSHA assumed employers use the
most inexpensive respirator permitted, taking into consideration the
employees' safety and compliance with regulatory requirements. These
assumptions most likely overestimate the cost of compliance because
many employers require their employees to use respirators when OSHA
does not require such use, or they require respirators with higher APFs
than OSHA currently requires. As a result, this analysis assumes shifts
in respirators that employers may have implemented already. Two
commenters on this issue agreed that these assumptions overestimate the
number of employers that would need to change respirators as a result
of this rule (see Exs. 9-16 and 13-8). One commenter (Ex. 9-16) noted
that ``For about twenty years, 3M has looked for worksites where
employers were using respirators at concentrations at the upper end of
the APF range. We have not been able to find these worksites.'' This
commenter went on to note, as a result ``we believe that the overall
compliance costs associated with the proposal, as currently written,
will likely be even lower than OSHA has estimated.''
    The Agency estimated distributions of exposures above the PELs
based on reports from its Integrated Management Information System
describing workplace monitoring of Sec.  6(b)(5) toxic substances
performed during OSHA health inspections. Of the 9,095 samples reported
above the PELs, 68.0 percent reported exposures between one and five
times the PEL, 13.1 percent found exposures between five and 10 times
the PEL, and 9.5 percent documented exposures between 10 and 25 times
the PEL. Exposures for the remaining 9.4 percent of the samples were
greater than 25 times the PEL. Based on these data, OSHA modeled the
current exposure distribution for each respirator type.
2. Incremental Costs of Upgrading Respirator Models
    OSHA also analyzed the costs of upgrading from the current
respirator to a more protective alternative. In doing so, OSHA
estimated the annualized unit costs for each respirator type, including
equipment and accessory costs, and the costs for training and fit
testing. One commenter (Ex. 17-9) noted the importance of not just
considering the initial costs of a respirator, but all associated
costs. OSHA has considered

all of these costs, including training, fit testing, program
development, and medical evaluation, as this commenter suggested. OSHA
then calculated the incremental cost for each combination of upgrades
from an existing model to a more protective one, taking into account
the effect of replacement before the end of the respirator's useful
life. These annualized costs range from $49.98 (for upgrading from a
supplied-air, demand mode, full facepiece respirator to a supplied-air,
continuous flow, half-mask respirator) to $963.73 (for upgrading from a
non-powered, air-purifying full facepiece respirator to a full
facepiece PAPR).
    In certain instances, workers who use respirators under the
substance-specific standards may have to upgrade to a SAR with an
auxiliary escape SCBA. Several substance-specific standards currently
specify SARs for exposures that exceed 1,000 times the PEL.\4\ OSHA
believes that workers are unlikely to regularly use respirators at such
extreme exposure levels, i.e., they are most likely to use them only in
exceptional, possibly emergency-related situations. Furthermore,
exposures at levels more than 1,000 times the PEL would generally be at
or above levels deemed immediately dangerous to life or health (IDLH),
so employers already are required by the Respiratory Protection
Standard to provide each worker with a respirator that has SCBA
capability. For these reasons, this PERFSA estimated no impacts for
these situations.\5\
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    \4\ These standards regulate cotton dust, coke oven emissions,
acrylonitrile, arsenic, DBCP, ethylene oxide, and lead.
    \5\ Paragraph (d)(2) of the Respiratory Protection Standard
requires employers to provide either a pressure demand SCBA or a
pressure demand SAR with auxiliary SCBA to any employee who works in
IDLH atmospheres.
---------------------------------------------------------------------------

3. Aggregate Compliance Costs
    For each respirator type affected by the regulation, OSHA combined
the incremental costs of upgrading to a more protective respirator, the
estimated share of users forecast to upgrade, and the number of users
involved to estimate the compliance costs associated with each
respirator type. Table V-4 shows estimated compliance costs for OSHA's
APF rule. The rule would require 1,918 users of non-powered air-
purifying respirators to upgrade to some respirator more expensive than
they are now using at a cost of $1.8 million. The Agency estimates that
22,848 PAPR users would upgrade their respirators at a cost of $2.3
million. A relatively small number of SAR users (5,110) would upgrade
to more expensive respirators at a cost of $0.4 million. Industry-
specific compliance costs vary according to the number of respirator
users and the proportion of these users affected by the rule.
Industries with relatively large compliance costs include SIC 17,
Special trade contractors ($0.8 million), and SIC 80, Health services
($0.8 million).
    As discussed previously, the Agency believes the actual costs of
the standard almost certainly are overestimated. The cost analysis
assumes all respirator wearers have levels of exposures that require
the particular respirator they are using. Under this assumption, 15,000
employees would be allowed to safely shift to a less expensive
respirator, which could lead to cost savings for the employer. Such
potential cost savings are not accounted for in this cost analysis.
    In many cases, employers use respirators when respirators are not
required by OSHA, or use respirators more protective than required by
OSHA. As a result, OSHA's cost analysis overestimates the number of
employees who are affected by the standard, and therefore overestimates
costs associated with the standard.

D. Benefits

    The benefits that would accrue to respirator users and their
employers take several forms. The standard would benefit workers by
reducing their exposures to respiratory hazards. Improved respirator
selection would augment previous improvements to the Respiratory
Protection Standard, such as better fit-test procedures and improved
training, contributing substantially to greater worker protection.
Estimates of benefits are difficult to calculate because of
uncertainties regarding the existing state of employer respirator-
selection practices and the number of covered work-related illnesses.
At the time of the 1998 revisions to the Respiratory Protection
Standard, the Agency estimated that the standard would avert between
843 and 9,282 work-related injuries and illnesses annually, with a best
estimate (expected value) of 4,046 averted illnesses and injuries
annually (63 FR 1173). In addition, OSHA estimated that the standard
would prevent between 351 and 1,626 deaths annually from cancer and
many other chronic diseases, including cardiovascular disease, with a
best estimate (expected value) of 932 averted deaths from these causes.
The APFs in this rulemaking will help ensure that these benefits are
achieved, as well as provide an additional degree of protection. These
APFs also will reduce employee exposures to several Sec.  6(b)(5)
chemicals covered by standards with outdated APF criteria, thereby
reducing exposures to chemicals such as asbestos, lead, cotton dust,
and arsenic.\6\ While the Agency did not quantify these benefits, it
estimates that 29,655 employees would have a higher degree of
respiratory protection under this APF standard. Of these employees, an
estimated 8,384 have exposure to lead, 7,287 to asbestos, and 3,747 to
cotton dust, all substances with substantial health risks.
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    \6\ In the 1998 rulemaking revising the Respiratory Protection
Standard, the Final Economic Analysis noted that the standard would
not directly affect the benefits for the estimated 5% of employees
who use respirators under OSHA's substance-specific health standards
(except to the extent that uniformity of provisions improve
compliance). Therefore, the Agency likely over-estimated the
benefits of that rulemaking since the standard did not affect
directly the type of respirator used by those employees (63 FR
1173). Conversely, this rule directly addresses the APF provisions
of the substance-specific standards; therefore, this rule would
affect directly the respirators used by employees covered by these
standards.
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    In addition to health benefits, OSHA believes other benefits result
from the harmonization of APF specifications, thereby making compliance
with the respirator rule easier for employers. Employers also benefit
from greater administrative ease in proper respirator selection.
Employers would no longer have to consult several sources and several
OSHA standards to determine the best choice of respirator, but could
make their choices based on a single, easily found regulation. Some
employers who now hire consultants to aid in choosing the proper
respirator should be able to make this choice on their own with the aid
of this rule. In addition to having only one set of numbers (i.e.,
APFs) to assist them with respirator selection for nearly all
substances, some employers may be able to streamline their respirator
stock by using one respirator class to meet their respirator needs
instead of several respirator classes. The increased ease of compliance
would also yield additional health benefits to employees using
respirators.
    Alternatively, these APFs would clarify when employers can safely
place employees in respirators that impose less stress on the
cardiovascular system (e.g., filtering facepiece respirators). Many of
these alternative respirators may have the additional benefit of being
less expensive to purchase and operate. As previously discussed, OSHA
estimates that over 15,000 employees currently use respirators that
fall in this group (i.e., shift to a less expensive respirator).
    One commenter (Ex. 9-16) agreed that the standard would have
significant benefits, saying:

    3M concurs with OSHA's conclusion that significant health
benefits will accrue to workers as a result of this rulemaking. 3M
believes that the majority of these benefits will be the result of
simplification of the respirator selection process for employers.
This will in turn lead to greater compliance with OSHA's various
standards regarding exposure to toxic and harmful substances. * * *
    In addition to these benefits from increased compliance, 3M also
concurs with OSHA's determination that the simplification and
clarification of the APF tables will result in lessening of
cardiovascular stress, as well as other potential stresses, because
of the ability to select a filtering facepiece respirator.

E. Economic Feasibility

    OSHA is required to set standards that are feasible. To demonstrate
that a standard is feasible, the courts have held that OSHA must
``construct a reasonable estimate of compliance costs and demonstrate a
reasonable likelihood that these costs will not threaten the existence
or competitive structure of an industry'' (United Steelworkers of
America, AFL-CIO-CLC v. Marshall (the ``Lead'' decision), 647 F.2d 1189
(DC Cir. 1980)).
    OSHA conducted its analysis of economic feasibility on an
establishment basis. Accordingly, for each affected industry, the
Agency compared estimates of per-establishment annualized compliance
costs with per-establishment estimates of revenues and per-
establishment estimates of profits. It used two worst-case assumptions
regarding the ability of employers to pass the costs of compliance
through to their customers: The no-cost-pass-through assumption, and
the full-cost-pass-through assumption. Based on the results of these
comparisons, which define the universe of potential impacts of the
APFs, OSHA then assessed the economic feasibility for all affected
establishments, i.e., those covered by this rule.
    The Agency assumed that establishments falling within the scope of
the standard would have the same average sales and profits as other
establishments in their industries. OSHA believes this assumption is
reasonable because no evidence is available showing that the financial
characteristics of those firms with employees who use respirators are
different from firms that do not use respirators. In the absence of
such evidence, OSHA relied on the best available financial data (those
from the Bureau of the Census (Ex. 6-4) and Robert Morris Associates
(Ex. 6-5)), used a commonly accepted methodology to calculate industry
averages, and based its analysis of the significance of the projected
economic impacts and the feasibility of compliance on these data.
    The analysis of the potential impacts of this standard on before-
tax profits and sales shown in Table V-5 is a ``screening analysis,''
so called because it simply measures costs as a percentage of pre-tax
profits and sales under the worst-case assumptions discussed above, but
does not predict impacts on these before-tax profits or sales. OSHA
used the screening analysis to determine whether the compliance costs
potentially associated with the standard could lead to significant
impacts on all affected establishments. The actual impact of the
standard on the profit and sales of establishments in a specific
industry would depend on the price elasticity of demand for the
products or services of these establishments.
    Table V-5 shows the economic impacts of these costs. For each
industry, OSHA constructed the average compliance cost per affected
establishment and compared it to average revenues and average
profits.\7\ These costs are quite small, i.e., less than 0.005 percent
of revenues; the one major exception is SIC 44 (Water transportation),
for which OSHA estimated the costs impacts to be 0.16 percent of
revenues. When the Agency compared average compliance costs with
profits, the costs also are small, i.e., less than 0.17 percent; again,
the major exception was SIC 44, which had an estimated impact of 2.12
percent of profits.\8\ Based on the very small impacts for
establishments in all industries shown in Table V-5, OSHA concludes
that the APF standard is economically feasible, in the sense of being
unlikely to close or alter the competitive structure of the affected
industries, for the affected establishments.
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    \7\ OSHA defines ``affected establishment'' as any facility that
uses respirators, as represented in the NIOSH-BLS survey data.
    \8\ For some industries, such as SIC 44, data from the NIOSH-BLS
survey were suppressed due to low response rates. In these cases,
the Agency, for the purposes of assessing economic feasibility,
imputed broader sector-level data from the survey to form an
estimate of respirator use. This procedure may result in
overestimating the impact of the standard (proposal) in some
industries. See the full FEA (Ex. 11) for further details.
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F. Economic Impacts to Small Entities

    OSHA also estimated the economic impacts of the rule on affected
entities with fewer than 20 employees, and for affected small entities
as defined by the Small Business Administration (SBA). Table V-6 shows
the estimated economic impacts for small entities with fewer than 20
employees: average compliance costs by industry are less than 0.005
percent of average revenues, and less than 0.19 percent of profits, in
all industries. Table V-7 presents the economic impacts for small
entities as a whole, as defined by SBA. For these firms, average
compliance costs are less than 0.005 percent of average revenues and
less than 0.03 percent of average profits. Thus, the Agency projects no
significant impacts from the rule on small entities.
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    When costs exceed one percent of revenues or five percent of
profits, OSHA considers the impact on small entities significant for
the purposes of complying with the RFA. For all classes of affected
small entities, the Agency found that the costs were less than one
percent of revenues and five percent of profits. Therefore, OSHA
certifies that this regulation would not have a significant impact on a
substantial number of small entities.

VI. Summary and Explanation of the Final Standard

    This section of the preamble provides a summary and explanation of
each revision made to OSHA's Respiratory Protection Standard involving
APFs.

A. Definition of Assigned Protection Factor

    As part of its 1994 proposed rulemaking for the Respiratory
Protection Standard, OSHA proposed a definition for APFs that read as
follows: ``[T]he number assigned by NIOSH [the National Institute for
Occupational Safety and Health] to indicate the capability of a
respirator to afford a certain degree of protection in terms of fit and
filter/cartridge penetration'' (59 FR 58938). OSHA proposed this
definition on the assumption that NIOSH would develop APFs for the
various respirator classes, building on the APFs in the 1987 NIOSH RDL
(59 FR 58901-58903). However, NIOSH subsequently decided not to publish
a list of APFs as part of its 42 CFR 84 Respirator Certification
Standards (60 FR 30338), and reserved APFs for a future NIOSH
rulemaking.
    During his opening statement on June 15, 1995, at an OSHA-sponsored
expert-panel discussion on APFs, Adam Finkel, then Director of the
Agency's Directorate of Health Standards Programs, noted that OSHA
would explore developing its own list of APFs (H-049, Ex. 707-X). The
Agency then announced in the preamble to the final Respiratory
Protection Standard (63 FR 1182) that it would propose an APF table
``based on a thorough review and analysis of all relevant evidence'' in
a subsequent rulemaking. In the final Respiratory Protection Standard,
OSHA reserved space for a table for APFs, a paragraph ((d)(3)(i)(A))
for APF requirements, and a definition of APF under paragraph (b).
    In its 1987 RDL, NIOSH defined an APF as ``[t]he minimum
anticipated protection provided by a properly functioning respirator or
class of respirators to a given percentage of properly fitted and
trained users'' (Ex. 1-54-437Q). ANSI subsequently developed a
definition for an APF in its Z88.2-1992 Respiratory Protection Standard
that reads, ``The expected workplace level of respiratory protection
that would be provided by a properly functioning respirator or class of
respirators to properly fitted and trained users'' (Ex. 1-50). The ANSI
Z88.2 subcommittee that developed the 1992 standard used the NIOSH
definition of an APF as a template for its APF definition. However, the
Z88.2 subcommittee revised the phrase ``minimum anticipated
protection'' in the NIOSH definition to ``expected workplace level of
respiratory protection.'' It also removed the NIOSH phrase ``to a given
percentage'' from its definition.
    The phrase ``a given percentage'' implies that some respirator
users will not achieve the full APF under workplace conditions. The
``given percentage'' usually is about five percent, which is a
percentage derived from statistical analyses of results from WPF
studies. In this regard, five percent represents the 5th percentile of
the geometric distribution of individual protection factors in a WPF
study. Therefore, the 5th percentile is the threshold for specifying
the APF for the respirator tested under those workplace conditions.
Using the 5th percentile means that about five percent of the employees
who use the respirator under these workplace conditions may not achieve
the level of protection assigned to the respirator (or class of
respirators), even after they receive proper fit testing and use the
respirator correctly under a comprehensive respiratory protection
program. However, ANSI dropped the phrase ``to a given percentage'' to
reduce confusion (i.e., the phrase did not specify a percentage), and
to emphasize the level of protection needed by the vast majority of
employees who use respirators in the workplace. See also subsection E.4
(``Analysis of Updated Database on APRs'') of Section III
(``Methodology for Developing APFs for Respirators'') of this preamble.
    The Agency's review of the available data on respirator
performance, as well as findings from surveys of personal protective
equipment (Exs. 6-1 and 6-2), indicate that existing APF definitions
are confusing to the respirator-using public. Accordingly, OSHA has
developed its own definition in this final rule that will reduce
confusion among employers and employees regarding APFs, thereby
assisting employers in providing their employees with effective
respirator protection, consistent with its Respiratory Protection
Standard.
    The major revision the Agency made to the ANSI APF definition in
developing the proposed APF definition included adding the phrase
``when the employer implements a continuing, effective respiratory
protection program as specified by 29 CFR 1910.134.'' The Agency added
this phrase to emphasize the already existing requirement that
employers must select a respirator in the context of a comprehensive
respiratory protection program. Also, the Agency revised the phrase
``as specified by 29 CFR 1910.134'' at the end of the proposed APF
definition to read ``as specified by this section'' to conform to style
conventions for referencing an entire standard. Therefore, the Agency
is adopting the APF definition that was proposed in the NPRM except for
this minor revision. OSHA's final definition for APF reads as follows:

    Assigned protection factor (APF) means the workplace level of
respiratory protection that a respirator or class of respirators is
expected to provide to employees when the employer implements a
continuing, effective respiratory protection program as specified by
this section.

B. APF Provisions

1. Paragraph (d)(3)(i)(A)--APF Provisions
    Paragraph (d)(3)(i)(A) is the provision in OSHA's Respiratory
Protection Standard that requires employers to use the APFs in Table 1
of this final standard to select respirators. The language of the final
provision is the same as the language in the proposal. Therefore,
paragraph (d)(3)(i)(A) in the final rule reads as follows:

    (A) Assigned Protection Factors (APFs). Employers must use the
assigned protection factors listed in Table 1 to select a respirator
that meets or exceeds the required level of employee protection.
When using a combination respirator (e.g., airline respirators with
an air-purifying filter), employers must ensure that the assigned
protection factor is appropriate to the mode of operation in which
the respirator is being used.

    The proposed language in paragraph (d)(3)(i)(A) also contained the
following note that addressed two issues related to APFs:

    Note to paragraph (d)(3)(i)(A): The assigned protection factors
listed in Table 1 are effective only when the employer has a
continuing, effective respiratory protection program as specified by
29 CFR 1910.134, including training, fit testing, maintenance and
use requirements. These assigned protection factors do not apply to
respirators used solely for escape.

    The first sentence of the note was proposed to remind employers
that the APFs in Table 1 are effective only when

they have a complete respirator program that meets the requirements of
OSHA's Respiratory Protection Standard. Table 1 of the final rule
already contains a note (footnote 2) that essentially repeats this
language. Therefore, to avoid unnecessary duplication, the Agency
decided to remove this language for the final rule. However, the Agency
is retaining the last part of the note as a footnote in Table 1 of the
final rule (see discussion of footnote 5 in the following subsection).
2. Table 1--APF Table
    The NPRM contained Table 1 (``Assigned Protection Factors''), which
listed the APFs for the various respirator classes. The final APFs for
these respirators are discussed in detail in subsection C (``Assigned
Protection Factors for Specific Respirator Types'') of this section.
    The proposed APF Table also contained a set of footnotes that
informed users regarding the application of APFs in the table. In the
final rule, footnote 1 remains essentially unchanged from the proposal.
Footnote 2 has been clarified to explain when APFs are effective,
rather than when APFs apply. All employers who use respirators need to
comply with the Respiratory Protection Standard. The language in
footnote 3 of the proposed table was revised from the proposal.
Proposed footnote 3 stated ``This APF category includes quarter masks,
filtering facepieces, and half-masks.'' The reference to quarter masks
has been removed from this footnote since quarter mask respirators have
been assigned a separate APF in Table 1. Also, the phrase ``with
elastomeric facepieces'' has been added to the description of half
masks to clarify that elastomeric facepieces are included in the half
mask respirator class. Final footnote 3 reads as follows in the final
rule: ``This APF category includes filtering facepieces, and half masks
with elastomeric facepieces.''
    Footnote 4 relates to the testing of PAPRs with helmets or hoods to
demonstrate that these respirators can perform at the required APF of
1,000 or greater for this class. The proposed footnote and the changes
made to it in the final standard are discussed in subsection C
(``Assigned Protection Factors for Specific Respirator Types'') in item
4 (``APF for Powered Air-Purifying Respirators (PAPRs)'') of this
section.
    Footnote 5 in the proposal described limitations for the APF of
10,000 (maximum) for pressure-demand SCBAs. The proposed footnote 5
described an SWPF study demonstrating that, when test subjects used
pressure-demand SCBAs under high work rates, a few of the study results
indicated that the respirators may not achieve an APF of 10,000.
Consequently, the proposed footnote cautioned employers not to use
these respirators under conditions that would require protection above
this level. In discussing this footnote in the proposal, OSHA stated
that, ``the employer must restrict [pressure-demand SCBA] use to
conditions in which the required level of employee protection is at or
below an APF of 10,000'' (68 FR 34105). While the Agency received no
comments on the proposed footnote, it believes that, when employers use
these respirators, they must assess the exposure conditions prior to
such use as required by paragraph (d)(1)(iii) of OSHA's Respiratory
Protection Standard. In view of the already existing requirement, the
Agency decided that the information in proposed footnote 5 was
unnecessary, and, therefore, removed it from the final rule.
    As noted previously under subsection B (``Paragraph (d)(3)(i)(A)--
APF Provisions'') of this section, OSHA is adding a new footnote 5 to
Table 1 in the final rule. The new footnote will remind employers that
they cannot apply the APFs specified in Table 1 to emergency-escape
conditions. OSHA believes this footnote is important because precise
exposures levels, which serve as the basis for determining APFs, cannot
be assessed accurately for emergency-escape conditions. Under these
conditions, the only appropriate respirators for employee use are
respirators designated for escape (i.e., escape respirators),
consistent with the requirements specified by OSHA's Respiratory
Protection Standard at 29 CFR 1910.134(d)(2)(ii). New footnote 5 is
similar to the APF provisions of the Agency's substance-specific
standards that designate appropriate respirators for use under
emergency-escape conditions. Because both the substance-specific
standards and 29 CFR 1910.134(d)(2)(ii) contain requirements for
selecting escape respirators, the Agency is revising the note slightly
to ensure that employers refer to the appropriate provisions.
Therefore, footnote 5 to Table 1 in the final rule will read as
follows:

    These APFs do not apply to respirators used solely for escape.
For escape respirators used in association with specific substances
covered by 29 CFR part 1910 subpart Z, employers must refer to the
appropriate substance-specific standard in that subpart. Escape
respirators for other IDLH atmospheres are specified by 29 CFR
1910.134(d)(2)(ii).

C. Assigned Protection Factors for Specific Respirator Types

    OSHA received comments on APFs during the public comment period
following publication of the NPRM, and at the public hearing. These
comments and hearing testimony are addressed in the following sections.
1. APF for Quarter Mask Air-Purifying Respirators
    Introduction. OSHA proposed an APF of 10 for quarter mask air-
purifying respirators (i.e., quarter masks/quarter mask respirators),
including them in the same category as filtering facepieces and half
mask air-purifying respirators (68 FR 43115). However, the Agency
specifically requested comment on whether this action was appropriate
(see 68 FR 34112).
    The following recommendations include all of the issues raised by
commenters regarding quarter mask respirators: assign them an APF of
10; assign them an APF of 5; prohibit their use altogether; or refrain
from assigning an APF to them until more studies become available. In
general, those commenters who recommended an APF of 10 for quarter mask
respirators based their recommendations on the analogous structural
characteristics (i.e., similarities in design) of quarter mask and half
mask respirators. Commenters who recommended an APF of 5 pointed out
that the only available APF data for quarter mask respirators were in
the 1976 study by Edwin C. Hyatt entitled ``Respiratory Protection
Factors'' (i.e., the ``Hyatt Study'' (Ex. 2)). Based on this study,
Hyatt assigned quarter masks an APF of 5.
    Comments regarding quarter mask respirators. The commenters who
advised OSHA to give quarter mask respirators an APF of 10 believed
that when these respirators are used in a workplace where the employer
has implemented a complete respirator program as required by 29 CFR
1910.134, their performance should be the same as that of half mask
respirators. For example, Thomas Nelson of Nelson Industrial Hygiene
Systems, Inc. testified,

    There is no unique property of a quarter mask respirator that
makes it[s] use different from half facepiece respirators provided
the person using the respirator is trained, fitted and maintains the
respirator. OSHA should include quarter masks in the half facepiece
category. (Ex. 10-17.)

    Michael Runge of 3M Corporation recommended that both half mask and
quarter mask respirators should receive an APF of 10 because of their
similarity

in performance, which he described as follows:

    [L]eakage into a respirator can occur through three pathways[:]
defects, filter penetration or faceseal leakage. Leakage through
defects is controlled by the respirator maintenance program. Quarter
facepiece respirators are no harder to maintain than half facepiece
respirators; they have many of the same parts * * * Filter leakage
is controlled by the NIOSH certification process * * * Faceseal
leakage is controlled through fit testing. The same fit tests can be
used with either type of respirator, hence the same maximum face
seal leakage would be expected for the quarter and half facepiece
respirator. (See Ex. 9-16.)

    Daniel Shipp and Janice Bradley of the International Safety
Equipment Association and Kenneth V. Bobetich of MSA made similar
statements (Exs. 9-22, 9-37, and 16-14).
    Thomas Nelson asserted that the Hyatt Study may have underestimated
the APF for quarter mask respirators because the study did not control
adequately for respirator leakage. His comment was based on the fact
that the authors of the study: (1) Did not administer a proper fit test
to the test subjects prior to measuring particle contamination inside
the respirator, and (2) used a fine particle (sodium chloride) as a
test aerosol, that may have penetrated both the faceseal and filter,
thereby artificially increasing concentrations inside the respirator
(Tr. at 163 and Ex. 18-9).
    The commenters who recommended that OSHA assign quarter mask
respirators an APF of 5 stressed that no studies, including WPF and
SWPF studies, on quarter mask respirators have been performed since the
Hyatt Study. Few quantitative data are thus available on which OSHA can
rely to set an APF for quarter mask respirators. These commenters, who
include NIOSH, pointed out that NIOSH used the Hyatt Study to set the
APF for quarter mask respirators at 5 in its 1987 RDL. NIOSH commented
further that, ``quarter mask respirators should be separated from half
mask respirators into a class of their own with an APF of 5. The data
from Hyatt's study [1976] do not support an APF of 10'' (Ex. 17-7-1).
Similarly, James S. Johnson stated, ``We object to the agency's
proposed APF of 10 for quarter mask respirators. There is no evidence
in the record, from either WPF or simulated workplace protection factor
(SWPF) studies that support this conclusion'' (Ex. 16-9-1). Johnson's
comments were echoed by the AFL-CIO (Exs. 9-27 and 19-1-1). These
comments indicate that the Hyatt Study was not a valid WPF or SWPF
study because it was a fit test protocol, not an experimental study.
    The International Brotherhood of Teamsters and the AFL-CIO Building
and Construction Trades Department supported an APF of 5 for quarter
mask respirators because they believed that quarter mask respirators
were more likely than half mask respirators to move around on workers'
faces when the workers communicate, or because of movement, exertion,
or perspiration. These commenters stated:

    Since the lower seal of the facepiece in quarter mask
respirators is on the chin, rather than below the chin, the seal is
much more likely to be compromised than the seal on a half face
respirator. Additionally, in use factors such as movement, exertion,
and perspiration add to the likelihood that the seal of these masks
will be compromised in the work place. (Exs. 9-12 and 9-29.)

    The Nuclear Regulatory Commission commented that its regulations
prohibit the use of quarter masks because of ``the potential lack of
stability of fit and the availability of acceptable alternatives (half-
face respirators)'' (Ex. 10-7). Tracy Fletcher of Parsons-Oderbrecht JV
recommended that OSHA prohibit the use of both quarter and half masks,
stating, ``Employees are required to wear eye protection with the
respirator, and use of the two together is difficult as the wearer will
find that the glasses rest on the nose piece of the respirator creating
an entry point for an overspray, splash or whatever.'' (Ex. 10-1.)
    A small number of commenters expressed the opinion that, because
the Hyatt Study provides the only data on the protection afforded by
quarter mask respirators, OSHA should reserve its decision on the APF
for these respirators until more studies can be completed. ORC
Worldwide commented that ``[q]uarter masks should be evaluated as
individual respirator models. In the absence of comprehensive testing
data over the last 27 years, there is no valid basis for giving them an
APF of any kind'' (Ex. 10-27). David Spence, an industrial hygienist,
stated:

    We recommend that SWPF studies be performed on quarter masks
respirators in a manner analogous to the ORC SWPF studies performed
on powered air-purifying respirators and supplied-air respirators.
To not delay publishing APFs for the other classes of respirators,
the section on APF of quarter masks could be reserved pending
completion of SWPF studies. (Ex. 10-6.)

    Summary and conclusions. In light of these comments, the Agency has
reconsidered the proposed APF of 10 for quarter masks. The comments
recommending an APF of 10 for quarter mask respirators are based solely
on structural analogies between quarter masks and half masks, and not
on the functional characteristics of these respirators. Accordingly,
the rulemaking record contains no quantitative or qualitative data or
other convincing evidence confirming that quarter mask and half mask
respirators function in a similar fashion to provide employees with
equal levels of respiratory protection. No WPF or SWPF studies
conducted on quarter mask respirators were submitted to the record. The
Hyatt Study, which consisted of testing quarter masks using a fit
testing protocol, provides the only data available for quarter mask
respirators, and it supports an APF of 5. Therefore, OSHA has decided
to separate quarter mask respirators into their own category and assign
them an APF of 5.
    It is possible that the facepieces of quarter masks and half masks
are not functionally analogous. Some commenters noted that half masks
rest under the chin while quarter masks rest on the chin. Consequently,
quarter masks are more prone than half masks to slip and compromise the
face seal when a worker talks or performs heavy work. While the record
contains no quantitative evidence supporting such assertions, there is
ample qualitative evidence, and OSHA is entitled under these
circumstances to take a conservative approach in weighing the available
evidence (see, e.g., 29 U.S.C. 655(b)(5) and United Steelworkers of
America, AFL-CIO-CLC v. Marshall, 647 F.2d 1189, 1248 (D.C. Cir.
1980)). Moreover, OSHA believes that these respirators can be used
safely at an APF of 5 because properly administered fit testing
protocols (including administering the fit test with glasses and other
protective equipment worn during respirator use),\9\ as well as
appropriate respirator training, will inform employees of this problem
and the procedures they can use to prevent it.
---------------------------------------------------------------------------

    \9\ As required under Appendix A (Part IA, paragraph 13) of 29
CFR 1910.134.
---------------------------------------------------------------------------

    In further response to those commenters who advised OSHA to
prohibit quarter masks, OSHA does not believe that this approach is
reasonable. As discussed at the public hearing, quarter mask
respirators are not widely used, but they do have some popularity in
particular industries (Tr. at 558). All existing quarter mask
respirators have received an N95 rating under NIOSH's certification
program, indicating that the respirators are designed to prevent at
least 95% of the challenge agent from penetrating the filter.
Therefore, these certification results, along with the

other evidence in the rulemaking record, have convinced OSHA that
employees can use these quarter mask respirators safely at an APF of 5
in workplaces that implement a respirator program that complies with 29
CFR 1910.134.
    Regarding those commenters who advised OSHA to delay the APF
decision for quarter mask respirators until WPF or SWPF studies are
available, OSHA notes that in the intervening 29 years following the
Hyatt Study, no WPF or SWPF studies have been conducted on quarter mask
respirators. If OSHA was to delay setting an APF for quarter mask
respirators pending further study, it could in effect be deciding to
delay setting an APF for these respirators indefinitely. OSHA has not
been persuaded by the record to delay setting an APF for quarter mask
respirators. Moreover, as noted in the previous paragraph, OSHA has
concluded that the record evidence supports an APF of 5 for quarter
mask respirators.
2. APF for Half Mask Air-Purifying Respirators
    Introduction. OSHA proposed an APF of 10 for both elastomeric and
filtering facepiece half mask respirators. During the public comment
period, interested parties expressed two divergent views on this
proposed APF. The healthcare industry (Ex. 9-18 to 9-21), NIOSH (Tr.
107 and 112) and other commenters (e.g., Exs. 9-11, 9-22, 9-26, 9-42,
and 10-18) agreed to an APF of 10 for both types of respirators, while
a number of commenters stated that filtering facepieces should be
assigned a protection factor of 5 (e.g., Exs. 9-8, 9-12, 9-29, and 10-
6; AFL-CIO Tr. at 122-126). The following sections discuss this issue
in detail.
    A number of reasons were presented for limiting filtering facepiece
half masks to an APF of 5. These reasons can be categorized generally
into concerns related to: (1) WPF studies and associated data; (2)
design of filtering facepiece respirators; (3) respirator use in the
workplace; and (4) ANSI standards. As discussed in Section III above,
some commenters believed that the WPF studies evaluated by OSHA
suffered from multiple problems (e.g., old data, studies not
representative of typical workplaces). While these points are addressed
in detail in Section III of this preamble, some of these concerns
warrant further discussion here.
    Some filtering facepieces do not achieve an APF of 10. Comment was
made that the data presented in the studies analyzed by OSHA indicate
that not all filtering facepieces achieved an APF of 10. Consequently,
these commenters argued that the entire class of respirators should
receive an APF of 5 (Exs. 9-29, 9-27, and 10-54). The AFL-CIO stated:

    An examination of the summary table of WPF studies for filtering
facepieces and half-mask elastomeric respirators at 68 FR 30495 of
OSHA's preamble to this proposed rule justifies our position. Of the
seven respirators that had a 5th percentile WPF less than 9, five of
[the] respirators that failed consisted of the filtering facepiece
style of respirator. Thus [of] the overwhelming majority of the half
mask respirators that failed, five of the seven or 71%, were
filtering facepieces. At the qualitative level then, this data
clearly indicates that most of the problem with failing to provide
adequate protection rests with filtering facepieces and not with
half-mask elastomerics. (Ex. 9-27.)

    The summary table in the proposal at 68 FR 34095 contains several
studies that were reviewed by OSHA, but did not meet the selection
criteria and were excluded from the quantitative analyses. The two
filtering facepiece respirators (one model in each study) evaluated in
these excluded studies had WPFs less than 9 (Cohen, Ex. 1-64-11; and
Reed, Ex. 1-64-61), while five of the respirators included in OSHA's
analyses failed to achieve a WPF of 9. Three of these five respirators
were filtering facepiece respirators and the remaining two respirators
were elastomeric half masks. As noted at the hearing, OSHA conducted a
Chi-square analysis to determine if the proportion of filtering
facepieces having a WPF less than 9 differed from the proportion of
elastomerics with a WPF less than 9 (Trans. at 135-136). This
statistical comparison showed that these proportions did not differ
significantly from each other, indicating that similar proportions of
filtering facepiece and elastomeric respirators performed at this
level--i.e., that the filtering facepiece respirators did not perform
more poorly than the elastomeric respirators.
    After updating the proposal's half mask WPF database (Ex. 20-2)
with new and additional data, Dr. Crump reanalyzed the database (Ex.
20-1). Plotting the observed protection factors for both the
elastomeric and the filtering facepiece half masks shows that over 95%
of each type of half mask attained an APF of at least 10. Moreover, a
review of these updated analyses reveals that more elastomeric than
filtering facepiece respirators failed to achieve an APF of 10 (see
Table 2 in Ex. 20-1). Even when the data from studies excluded from
these analyses were added to the database, over 95% of the WPFs for
both types of half mask (separately and combined) are still equal to or
greater than 10. (A detailed discussion of Dr. Crump's analyses can be
found in section III (Methodology) of this preamble.) Therefore, OSHA
does not agree that the evidence in the record supports an APF for
filtering facepieces of 5 as suggested by these commenters.
    Respirator configuration and certification issues. Commenters also
stated that not all configurations (e.g., cups, duckbills, fold flats)
of filtering facepiece respirators have been studied (e.g., Exs. 9-17,
9-34, 9-40, 10-33, and 10-34; Tr. at 204-205). In addition, some
commenters mentioned that none of the respirators in the studies
evaluated by the Agency for the proposal were certified under NIOSH's
new 42 CFR 84 requirements (Exs. 9-33, 9-34, 10-22, and 10-38). The
focus of these comments was that OSHA should not assume that all
filtering facepieces perform the same as those filtering facepieces
that were tested. These commenters believed that filtering facepiece
half masks should be given an APF of 5 because, in their view, there is
a lack of information on 42 CFR 84 filtering facepieces.
    OSHA recognizes that its analyses do not encompass all
configurations or models of filtering facepiece half masks. However,
this is true for all types of respirators, not just filtering facepiece
half masks. Since filter efficiency is certified by NIOSH, the filter
media of all filtering facepiece (and elastomeric) half mask
configurations are equivalent. Therefore, any differences in
performance would arise from variations in faceseal leakage among the
different configurations. OSHA's Respiratory Protection Standard
requires that all respirator users pass a respirator fit test to ensure
that a minimum acceptable faceseal performance is achieved. Therefore,
because all respirators must be used in accordance with the Respiratory
Protection Standard, the Agency sees no reason to conclude that
differences in configuration will result in performance variations. In
addition, Section III of this preamble discusses two studies that
compare the workplace performance of 42 CFR 84 and 30 CFR 11 filtering
facepiece half masks. The 42 CFR 84 respirators demonstrated superior
performance when compared to the 30 CFR 11 respirators. OSHA concludes
that, based on the more stringent filter efficiency certification
requirements and these study results, 42 CFR 84 respirators provide
performance at least equal to 30 CFR 11 respirators. Therefore, the
record evidence does not support lowering the APF for filtering
facepieces to 5.

    Determining faceseal leakage. Several commenters mentioned that
NIOSH had eliminated the fit test portion of its certification
procedures. They believed that as a result of this NIOSH action, one
could not be sure if a filtering facepiece respirator achieves an
adequate faceseal and provides the expected protection (Exs. 9-8, 9-27,
9-29, 9-34, 9-35, 9-40, 9-41, 10-22, 10-33, 10-38, 10-50, and 10-55).
During the public hearing, NIOSH indicated that it would establish a
new respirator certification testing procedure, stating:

    Such changes would result in additional certification tests to
assure or assess the overall performance of every respirator model,
and thus assure that every model is capable of providing a level of
protection consistent with the class APF. (Tr. at 103.)

    Several commenters supported this approach, and indicated that
implementing such a procedure would be beneficial. For example, Tim
Roberts (Exs. 17-8 and 18-4) stated that the procedure would help to
identify respirators that may not have adequate workplace performance.
The AFL-CIO (Ex. 19-1) believed that while the procedure would help
assure certified filtering facepieces are capable of fitting an
employee properly, these respirators should still be given an APF of 5.
    Two respirator manufacturers also addressed this issue. The 3M
Company commented that no evidence exists showing that employee
protection would be enhanced by adding a fit test requirement to
NIOSH's certification procedures, and added that proper respirator fit
must be determined by fit testing each wearer (Ex. 18-7). When asked by
OSHA about the proposed NIOSH testing, Jay Parker of Bullard responded
that he believed such testing would be an improvement over the current
procedures (Tr. at 497).
    OSHA has reviewed this information and supports NIOSH's plans to
add performance testing to its respirator certification procedures. The
Agency agrees with the 3M Company that proper facepiece fit can only be
assured through individual fit testing. However, OSHA also agrees with
Tim Roberts that performance testing will assist in identifying
respirators with poor fitting characteristics that may not provide
protection consistent with the respirator's APF. Thus, OSHA concludes
that performance testing will enhance the information needed for
selecting appropriate respirators, and encourages NIOSH to expedite its
efforts in this area. However, employers and respirator users should
note that using a respirator certified by NIOSH through performance
tests would not preclude individual fit testing as required by OSHA's
Respiratory Protection Standard.
    Filtering facepiece design problems. Several commenters urged an
APF of 5 for filtering facepiece half masks based on the design
characteristics of these respirators. Some commenters expressed concern
that, in comparison to elastomeric half masks, filtering facepieces are
poorly constructed (e.g., non-adjustable head straps, prone to crushing
or denting, facepiece too stiff or too soft) (e.g., Exs. 9-34, 10-37,
10-38, 10-54, and 12-7-1). For example, T.C. Lefford of Fluor Hanford
stated:

    Elastomeric half-mask respirators provide a better face seal
that filtering facepieces (Disposable respirators or maintenance-
free masks). Most elastomeric half-mask respirators are made of more
pliable silicone rubber that provides a much better seal on the
face. Elastomeric half-mask respirators have three sizes with
adjustable head straps and a head cradle to improve stability while
the majority of filtering facepieces have one or two sizes and the
head straps are non-adjustable. (Ex. 9-32.)

    OSHA believes that concerns about loose, dented, or crushed
filtering facepieces are addressed adequately by compliance with
existing program requirements under 29 CFR 1910.134(d) and (g).
    In addition, comment was received alleging that the 42 CFR 84
requirements for increased filter efficiency result in respirators with
stiff facepieces, poor face seals, and high breathing resistance,
thereby producing filtering facepieces with increased faceseal leakage
(e.g., Exs. 9-34, 9-41-1, 10-46, and 10-50). Mark Haskew, Tim Roberts,
and Ching-tsen Bien (Exs. 12-7-1, 16-12, 16-20-3, and 17-5) also
expressed concern about the increased filter efficiency requirements of
the new 42 CFR 84 certification standards and their effect on the
performance of filtering facepiece respirators. In their written
comments, Mark Haskew and Tim Roberts stated that the 42 CFR 84 filter
efficiency requirements ``would increase the breathing resistance and
in turn cause an increase in faceseal leakage when compared to 30 CFR
part 11 filtering facepieces'' (Ex. 12-7-1). Haskew, Roberts and Bien
also questioned the ability of 42 CFR 84 filtering facepieces to fit
the user's face, and the applicability of 30 CFR part 11 study data to
42 CFR 84 respirators. For example, Mark Haskew testified:

    The other problem with the old data is that the 30 CFR 11
respirators are significantly different in performance, or at least
we would anticipate that they may be different in the performance
that they provide. Based on the newer filter media with the 95, 99
and 100 series, there's an allowance for increased breathing
resistance. And because the efficiency has to be greater, the filter
media itself tends to be stiffer. And the concern we have, of
course, which is untested in the research as far as we know, is that
it may not conform as well to a wearer's face. (Tr. at 203.)

    Based on their opinion that manufacturers would have to produce
thicker, stiffer filter media to meet the new filter efficiency
requirements, these commenters concluded that the data for 42 CFR 84
filtering facepieces would show a decrease in performance compared to
the older 30 CFR 11 respirators. These commenters, based on this
assumption, concluded that it would be inappropriate to set the APF for
filtering facepieces based on WPF studies of the older 30 CFR 11
respirators. However, they presented no data to substantiate this
claim.
    When NIOSH published the 42 CFR 84 respiratory protective devices
final rule (60 FR 30336), Section 84.180 of this rule increased the
maximum allowable breathing resistance levels during inhalation to 35
mm (of water pressure), and during exhalation, to 25 mm. NIOSH
explained this increase as follows:

    [It will] enable manufacturers to produce respirators meeting
the new requirements more expeditiously and at lower cost. * * *
This small increase in maximum allowable breathing resistance for
particulate respirators does not add substantially to physiologic
burden for respirator users, and will be compensated for by
increased worker protection provided by the new filter efficiency
tests and classification system. (60 FR 30346.)

    However, when respirator manufacturers developed new particulate
filters to meet the 42 CFR 84 performance requirements, they were able
to meet them without increasing the breathing resistance levels. For
example, the 3M Company submitted the following table of breathing
resistance values for several classes of 42 CFR 84 filters made by
different manufacturers (Ex. 17-9-1, page 6; derived from a paper
submitted by 3M to the OSHA docket (Ex. 9-16-1-3)).

------------------------------------------------------------------------
                                    Manufacturer A      Manufacturer B
          Filter Class             ([Delta]P mmH2O)    ([Delta]P mmH2O)
------------------------------------------------------------------------
N95.............................  11.5..............  9.7
R95.............................  No Product........  13.6
P95.............................  14.9..............  No Product
P100............................  23.9..............  17.3
------------------------------------------------------------------------

    No measurement in this table exceeds the 30 CFR 11 limit of 30 mm
of water pressure. As the 3M Company stated, ``Breathing resistance of
42 CFR 84 respirators are contained within the range of breathing
resistances allowed for 30 CFR 11 respirators, rather than being
significantly higher'' (Ex. 16-25-2, page 17).
    OSHA also received comments that higher breathing resistance leads
to increased faceseal leakage (Exs. 9-34, 9-35, 9-41, 10-38, and 10-
50). During the public hearings, 3M submitted two new studies of
filtering facepiece respirators certified under 42 CFR 84 (Ex. 16-25-
3). The 42 CFR 84 certified filtering facepieces used in these studies
performed better, overall, than comparable filtering facepieces
certified under 30 CFR 11 (see discussion above under Section III
(``Methodology, etc.'')). These results indicate that faceseal leakage,
if it existed, did not impair the performance of these filtering
facepieces.
    At the 2004 AIHCE in Atlanta, Georgia, Larry Janssen of the 3M
Company presented the results of a recently completed study (Ex. 17-9-
1) using the OHD FitTester 3000 controlled negative pressure (CNP) fit
testing instrument to measure faceseal leak rate (i.e., a drop in
pressure inside the mask). Leak-rate measurements first were made using
the negative pressure and flow-rate settings listed for the CNP fit
test in Appendix A of 29 CFR 1910.134. Without disturbing the fit of
the respirator, four additional leak-rate measurements then were made
at four different negative pressures and flow rates ranging from 5.6
through 20.1 mm of water pressure, followed by a final measurement at
the CNP fit test rates. Janssen found that test subjects with a fit
equal to or greater than a fit factor of 100:

    [D]id not show any increase in leak rate as pressure drop
increased. Subjects with a fit factor below 100 * * * showed
significant variability in leakage as the settings were changed, but
the amount of leakage did not correlate with increasing pressure
drop, i.e., sometimes the leakage was higher and sometimes lower.
(Ex. 18-7, page 49.)

    The 3M Company concluded that the study ``demonstrates the value of
fit testing: respirators that fit well enough to be assigned to a
worker do not exhibit increased leakage as pressure drop increases''
(Ex. 18-7, page 49). Janssen, in a summary of this study that he
presented at the May 2004 AIHCE stated, ``Results of this study do not
support the concept of increased faceseal leakage with increased
pressure drop.''
    While concern was expressed by some commenters about increased
filter efficiency requirements resulting in increased breathing
resistance and faceseal leakage, no data were submitted to support this
viewpoint. However, studies were submitted that demonstrated that 42
CFR 84 filtering facepiece respirators perform at least as well as 30
CFR 11 filtering facepieces, and that increased filter efficiency does
not result in increased faceseal leakage. After reviewing this
information, OSHA is persuaded that 42 CFR 84 half masks are as
protective as 30 CFR 11 half masks and that increased face seal leakage
in such respirators has not been demonstrated by evidence in the
record. Therefore, these arguments do not support an APF for filtering
facepieces of 5.
    The efficacy of user seal checks provided by respirator
manufacturers also was questioned by several commenters. These
commenters stated that user seal checks for filtering facepieces either
could not be performed or were more difficult than user seal checks
with elastomeric facepieces (e.g., Exs. 9-27, 9-31, 9-34, 9-35, 9-40-1,
9-41-1, and 10-54). In general, their opinion was that the inability to
perform an adequate user seal check on filtering facepiece respirators
would lead to decreased protection, thereby warranting a reduced APF
for this type of respirator.
    Bill Kojola of the AFL-CIO (Exs. 9-27 and 19-1) stated that ``user
seal checks are rarely performed on filtering facepieces in the field
and * * * it is extremely difficult, if not impossible, to perform
effective user seal checks on filtering facepieces.'' He stated that it
was ``easy for wearers to perform effective user seal checks on
elastomerics.'' Kojola cited this difficulty in performing user seal
checks as a reason for separating filtering facepieces from
elastomerics, and giving filtering facepieces an APF of 5. However, he
did not provide any data to support his experience that filtering
facepieces demonstrate a difference in user seal check performance
compared to elastomerics.
    Similar concerns were voiced by Mark Haskew (Exs. 17-5 and 18-3),
Tim Roberts (Exs. 9-8, 10-55, and 17-8), and Ching-tsen Bien (Exs. 9-
43-2 and 18-5). In addition, Mark Haskew stated that filtering
facepieces with adjustable nose pieces cannot normally obtain
repeatable fit factors. However, these commenters did not submit any
supporting data for this contention. In his post-hearing submission,
Tim Roberts (Ex. 18-4) stated that data demonstrating this difference
in performance are not available.
    James Johnson (Exs. 10-33, 16-9-1, and 17-10) also stated that
filtering facepieces cannot be fit checked effectively, and presented
results from a series of fit tests he performed on himself with
filtering facepieces and elastomeric half masks. Three of the four
elastomeric half masks that he tested passed a positive or negative
user seal check, and consistently achieved a fit factor of 1500 or more
using the Portacount fit test instrument. One elastomeric half mask did
poorly (fit factor of less than 100), and it was identified clearly as
a failure by a user seal check and a subsequent fit test. He found that
it was difficult to achieve a minimum fit factor of 100 or greater with
filtering facepieces using the Portacount Companion fit test
instrument. However, two of the eight filtering facepiece models he
tested achieved fit factors of 100 or greater. He stated that he was
able to identify obvious leaks with the filtering facepieces he tested
by exhaling heavily and sensing the airflow, but that cupping his hands
over the facepiece was not an effective user seal check for him. He
stated further that these preliminary fit test results demonstrated a
significant difference in performance between elastomeric and filtering
facepiece half masks, and that OSHA should give filtering facepieces an
APF of 5 based on these results.
    The numerical differences in fit factors between filtering
facepieces and elastomeric half masks reported by Johnson may not be
significant. Achieving a fit factor of 170, as Johnson did with the 3M
9211 foldable filtering

facepiece using the Portacount Companion, is not necessarily worse than
achieving a fit factor of 2200 with a MSA Comfo elastomeric half mask
using the Portacount alone. In this regard, the fit test instruments
identified the elastomeric half masks and filtering facepieces that
provided adequate fits on Johnson (i.e., they met their required fit
factor of 100), and he was able to perform user seal checks with both
respirators. Therefore, OSHA finds that these fit test measurement
differences are not a convincing argument for an APF for filtering
facepiece respirators of 5. The Agency believes that Johnson's pilot
study proves only that some makes and models of filtering facepieces
are not suitable for his face size and shape. When he wore a filtering
facepiece or elastomeric respirator that fit him, an APF of at least 10
was achieved.
    In response to these concerns, the 3M Company (Ex. 17-9-2) and the
Aearo Company (Ex. 17-3-1) submitted to the record instructions for
conducting user seal checks on their filtering facepiece respirators.
The Aearo Company instructs users to cup their hands over the
respirator to test the seal, stating: ``If air flows around your nose,
tighten the nosepiece; if air leaks around the edges, reposition the
straps to fit better (Ex. 17-3-1).'' User seal check instructions for
3M filtering facepieces read, ``If air leaks between the face and
faceseal of the respirator, reposition it and readjust the nose clip
for a more secure seal'' (Ex. 17-9-2).
    In their post-hearing comments (Exs. 9-16, 17-9-1, 18-7, and 19-3),
3M responded to the comments raised at the public hearing regarding the
difficulty or impossibility of performing user seal checks on filtering
facepiece respirators. The 3M Company pointed out that no data were
offered to support this position, nor was recognition given to the
methods contained in both the 1980 and 1992 editions of the ANSI Z88.2
respirator standard for performing user seal checks. The 3M Company
also cited a study in the docket by Myers et al. (Ex. 9-16-1-13), which
concluded that no difference was found in the effectiveness of
performing user seal checks on filtering facepiece respirators or
elastomeric respirators. This study also referenced a comment by Daniel
K. Shipp of the ISEA (Ex. 9-22) that user seal checks can be performed
with filtering facepieces. A second evaluation of user seal checks
submitted by 3M (Ex. 17-9-10) involved the use of a 3M flat-fold
filtering facepiece by novice respirator users. It showed that novice
respirator users can be trained to effectively perform user seal
checks, and that the use of seal checks improved the overall quality of
respirator fit.
    The 3M Company also stated that the ease or difficulty in
performing user seal checks is based on many factors. These factors
include difficulty in performing a user seal check on some elastomeric
respirators when the exhalation valve cover must be removed without
disturbing the fit. Also, it can be difficult to perform a user seal
check on elastomerics by blocking off the filter when a respirator user
has small hands. In addition, 3M cited an analysis from its report at
the 2001 AIHCE (Ex. 4-10-7) that showed no significant differences in
WPF results for filtering facepieces measured in the morning and
afternoon, with repeated redonnings of the respirators performed during
each of these periods. These results indicate that the user seal check
conducted after each redonning was effective in ensuring proper
respirator fit.
    During the rulemaking, several commenters referred to the use of
fit check cups to perform user seal checks. These devices are designed
to assist the respirator user in performing a positive and negative
pressure seal check by covering the surface of a filtering facepiece
respirator. For example, Tim Roberts stated:

    One of the manufacturers did recognize that there was difficulty
in doing these types of fit checks, and they designed, and
constructed, and sold a fit-check cup that actually fit over the
facepiece of a respirator, a filtering facepiece respirator, so that
it would actually check the seal in a more conventional manner. We
think that that may be another alternative approach to assuring that
these respirators fit properly if there was a requirement to do
that. (Tr. at 216.)

    Another commenter who discussed the use of fit check cups was
Donald Faulkner of the United Steelworkers, who stated during his
questioning of Warren Myers:

    [W]e don't see a real good fit with the hands-over filtering
facepiece. That's why the cups were developed by many manufacturers,
but we don't see them being utilized, bought, or anything else. (Tr.
at 95.)

    He elaborated in his post-hearing comment: ``Filtering facepieces
do not allow seal checks to be performed without the assistance of
additional equipment [i.e., fit check cups] that is never provided by
the employers, as being cost prohibitive.'' (Ex. 19-2.)
    Bill Kojola of the AFL-CIO (Tr. at 132) and George Macaluso of the
Building Construction Trades Department of the AFL-CIO (Tr. at 654)
made similar statements regarding the infrequent use of fit check cups,
i.e., that they are generally not used in the workplaces their unions
represent. They asserted that user seal checks that involve cupping the
hands over the facepiece were not effective, and that the use of fit
check cups should be required by OSHA. They implied that fit check cups
are a generic device for doing user seal checks, and that one
manufacturer's fit check cup can be used with other types of filtering
facepieces. On the other hand, Ken Wilson of the Ohio Board of Water
Quality, Division of Safety and Hygiene (Ex. 10-3) stated that he has
not seen fit check cups used in the field, and doubted that their use
would allow a respirator user to achieve a successful fit check.
    OSHA has considered carefully the opinions presented about fit
check cups and user seal checks. The Agency recognizes that the use of
a fit check cup is one way of performing a user seal check. However,
these cups can be inconvenient when used in the workplace on a daily
basis. In this regard, each respirator user would need ready access to
a fit check cup, not only to perform the required user seal checks when
initially donning the respirator, but for any repeated respirator
donnings that occur throughout the workday. The fit check cup would be
another piece of equipment for respirator users to carry with them, and
it can be misplaced. However, most respirator manufacturers have not
adopted the use of fit check cups, and these manufacturers recommend
cupping the hands over the filtering facepiece to perform a user seal
check. As the 3M Company stated in describing the use of fit check
cups, ``Based on our experience, user seal checks without cups are
effective, more convenient, and easier to perform'' (Ex. 17-9-1, page
4).
    Since only a few respirator manufacturers have fit check cups, it
is not surprising that they are seldom used in the workplace. The fit
check cups that exist are designed by the respirator manufacturer to
work with a specific facepiece configuration and respirator model, and
the cups do not necessarily work with other models of respirators, even
models made by the same manufacturer. OSHA knows of only one series of
42 CFR part 84 filtering facepiece respirators that have fit check cups
available.
    OSHA does not find merit in the comments that fit check cups are
necessary to perform user seal checks with filtering facepieces. While
a fit check cup designed to work with a particular model of respirator
can be used to perform a user seal check, it is not the only way to
perform this function. Accordingly, the Agency believes that respirator
users can follow

a respirator manufacturer's instructions to perform a user seal check,
e.g., whether the seal check involves cupping the hands over the
facepiece or the use of a fit check cup.
    The OSHA Respiratory Protection Standard requires that an employee
perform a user seal check to use a respirator. The WPF database that
OSHA developed contains over 1,000 WPF data points for half mask
respirators collected from workers using respirators in programs that
included user seal checks. Analyses of these data showed that the
filtering facepiece respirators achieved an APF of 10. These data are
derived from WPF studies in which user seal checks were performed on
filtering facepiece respirators by 100s of workers. In addition, 3M's
analysis (Ex. 4-10-7) indicates that user seal checks performed on
filtering facepieces ensure proper redonning of these respirators. When
a respirator user cannot perform a user seal check with a particular
respirator model, then that respirator cannot be used by that employee,
and the employer must find another respirator model on which a user
seal check can be performed. This requirement applies to all tight-
fitting facepieces, including filtering facepieces and elastomeric half
masks. How easy or difficult it is for an employee to perform a user
seal check on a particular type of respirator is not an issue that
precludes other employees from using that respirator. Therefore, the
comments on user seal checks do not provide convincing evidence that
would support decreasing the APF for filtering facepieces to 5.
    OSHA argued previously in National Cottonseed Products Association
v. Brock, 825 F.2d 482 (D.C. Cir. 1987) that filtering facepieces used
to protect employees against exposure to cotton dust should have an APF
of 5 based on the difficulty of fit testing, particularly fit checking
on a daily basis. However, the Agency now believes that the record
evidence for this rulemaking shows that the industrial-hygiene research
community has developed and refined qualitative and quantitative fit
tests, as well as developed sophisticated techniques for determining
respirator leakage. Several commenters (Exs. 16-25-3 and 17-9-1)
provided evidence that filtering facepieces could be fit tested and
then used effectively. Seal-check techniques and procedures (e.g., fit-
test cups, manual testing) also have been developed to help ensure that
filtering facepieces maintain their fit while being worn in the
workplace. These new developments allowed the Agency to reassess
filtering facepieces and find that these respirators can be reliably
fit tested and fit checked.
    The WPF studies provide further support for this conclusion. In
fact, every WPF study of filtering facepieces in the OSHA APF database
involved fit testing the respirator, using the new and refined methods,
prior to the worker using the respirator in the study. Researchers used
the available fit testing and checking technologies and methodologies
in the studies to be assured that employees would be protected during
the study by the respirators when exposed to airborne contaminants up
to 10 times the PEL, and so that they could determine the results of
the study would be accurate.
    Non-compliance and economic incentive issues. Several commenters
asserted that filtering facepiece half masks should be given an APF
less than 10 because employers do not comply with the Respiratory
Protection Standard (e.g., by not performing fit testing) (e.g., Exs.
9-40-1, 10-33, and 10-52; Tr. at 663). In this regard, Donald Faulkner
of the United Steelworkers of America (USWA) stated:

    We observe in many worksites that the employers are issuing
filtering masks as if they were candies. They don't have respiratory
protection programs, requirements to be clean shaven, and no medical
or no idea of the MUC of the contaminant that the worker needs to be
protected from. (Ex. 9-40-1.)

    However, the 3M Company commented that non-compliance with the
Respiratory Protection Standard should not be a factor in determining
APFs, noting:

    OSHA has appropriately made the proposed APFs contingent upon
the existence of an effective and well-managed respiratory
protection program. This is the only circumstance under which APFs
can be used. Setting APFs on assumptions of poor fit and lack of
training is impossible because of the countless variables that exist
in the workplace and workforce. APFs can only apply under properly
managed respiratory protection programs. This is supported by
following the American Industrial Hygiene Association Respiratory
Protection Committee definition of APFs: An APF is the level of
respiratory protection that a properly functioning respirator or
class of respirators would be expected to provide to properly fitted
and trained users in the workplace. The APF takes into account all
expected sources of facepiece penetration (e.g., face seal
penetration, filter penetration, valve leakage). It is not intended
to take into account factors that degrade performance such as poor
maintenance, failure to follow manufacturers' instructions, and
failure to wear the respirator during the entire exposure period.
(Ex. 9-16.)

    Several commenters voiced concern that assigning a protection
factor of 10 to both elastomeric and filtering facepiece half masks
will result in an economic incentive for employers to provide filtering
facepiece respirators to employees rather than elastomeric half masks.
These commenters assumed that the less expensive filtering facepiece
respirators were less protective than the more expensive elastomerics
(e.g., Exs. 9-29, 10-38, and 10-54; Tr. at 212-213 and 659-660). The
USWA expressed this concern, stating, ``If OSHA gives the filtering
face piece type of respirator an APF of 10, employers would interpret
this as `let's take the cheap way out.' It will be a dis-incentive to
issue to workers the proven protection of the elastomeric face piece
respirator'' (Ex. 9-40-1). Responding to an OSHA question about this
issue, Thomas O'Connor of the National Grain and Feed Association
stated:

    Well, clearly, if [you] had two respirators that provided the
comfort and fit to the employee that's needed and one was half the
cost of the other one, obviously anybody would select the lower cost
respirator. But as I noted, that's not the primary motivation, cost.
The primary motivation is complying with the standard, making sure
that the employee[s] wear it and it fits properly and it's
comfortable. * * * If an employee's wearing a respirator that's not
comfortable, there's going to be an incentive for them possibly not
to wear that respirator * * * when they should be wearing it. So
from our perspective, comfort is one of the primary considerations
in selecting a respirator for an employee. (Tr. at 684-685.)

    OSHA considered these comments and concludes that neither cost nor
non-compliance with the Respiratory Protection Standard is an
appropriate basis for determining the final APF for half masks.
Employers are required to comply with all the provisions of the
Respiratory Protection Standard. Non-compliance is not an option for
employers. Thus, there is no compliance reason to reduce the APF for
half masks.
    As to whether assigning a protection factor of 10 to filtering
facepiece half masks will provide an economic incentive to use these
respirators, OSHA concludes that so long as a respirator achieves an
APF of 10, it doesn't matter what respirator an employer uses. Once
again, OSHA's data analyses, as well as consensus standards, show that
filtering facepieces can attain an APF of 10.
    ANSI's updated APF of 5. Several commenters noted that the recent
draft of the ANSI Z88.2 respirator standard gave filtering facepieces
an APF of 5 (e.g., Exs. 9-8, 10-51, and 10-54; Tr. at 124-125 and 197-
201). For example, Bill Kojola of the AFL-CIO testified:

    The AFL-CIO's position that filtering facepieces should be given
an APF of 5 is

also provided by other organizations with considerable expertise on
respiratory protection. Indeed, the ANSI Z88.2 Committee, charged
with the responsibility for the American standard for respiratory
protection, has recently proposed an APF of 5 for filtering
facepiece respirators. We believe that OSHA should give serious
consideration to this ANSI position as well when it issues its final
rule. (Tr. at 124-125.)

    OSHA considered the draft ANSI standard during this APF rulemaking.
However, this draft standard currently is under appeal, and has not
been designated by ANSI as a final standard (Ex. 17-9-10-2). Jill
Snyder, Standards Coordinator for the AIHA secretariat of the ANSI Z88
committee, addressed the status of the draft ANSI Z88.2 revised
respiratory protection standard in an e-mail sent to participants in
Roundtable 228 held at the 2004 AIHCE. This e-mail stated:

    Until a standard is approved by ANSI, it is not an ANSI
standard. Therefore, we should not say things like `ANSI completed
drafting * * *' etc. It is actually the Accredited Standards
Committee (ASC) Z88 or Z88.2 that put together what is still the
DRAFT standard. We also have to make sure we call it a draft
standard, not a standard at this point. (Ex. 17-9-10-2.)

    The method used by ANSI to determine the draft APFs also differs
from OSHA's approach, which used data analyses and expert opinion to
arrive at the final APF for half masks. James Johnson, representing the
ANSI Z88.2 subcommittee, stated that the subcommittee did not perform
an extensive quantitative analyses similar to OSHA's in determining the
draft APFs (Tr. at 357). In response to questions from Thomas Nelson,
ANSI subcommittee member George Macaluso confirmed that an overall
tabulation and review of available WPF data was not conducted by the
ANSI subcommittee in determining APFs (Tr. at 663-666).
    With regard to the decision of the ANSI subcommittee, James Johnson
agreed that a subcommittee composed of other members may have reached a
different conclusion regarding the APF for filtering facepiece half
masks (Tr. at 354-355). He also stated:

    There's nothing in the consensus process that says every part of
the standard has to have an absolute defendable, scientific,
technically traceable base. It doesn't exist. It's not there. We
have tremendous numbers of standards that are out there that the
professionals develop with the best knowledge and experience that
they have, and this is the process. (Tr. at 363.)

    Summary and conclusions. In this section, OSHA considered the issue
of the appropriate APF for filtering facepieces. OSHA's data analyses
in the record support an APF of 10 for filtering facepiece respirators.
Moreover, a number of commenters supported the APF of 10. Some
commenters recommended a lower APF for filtering facepieces than
proposed based on the poor structural integrity of the mask, the
availability of additional models of respirator protection, poor
compliance with the respirator program requirements, difficulty
performing user seal checks, increased breathing resistance among
filtering facepieces approved under 42 CFR part 84, and the recent ANSI
draft APF for filtering facepieces. As discussed in the previous
sections, the evidence in the record with regard to these issues
justifies retaining in this final rulemaking the proposed APF of 10 for
filtering facepieces.
3. APF for Full Facepiece Air-Purifying Respirators
    Introduction. In a 1976 report, Ed Hyatt of LANL developed an APF
table that included this respirator class (Ex. 2). In this report,
Hyatt used the results from quantitative fit testing to assess six
models of full facepiece negative pressure air-purifying respirators
equipped with HEPA filters. Five of these respirators achieved a
protection factor of at least 100 for 95% of the respirator users. The
sixth respirator attained this level of protection for 70% of the
users. Based on the results for the sixth respirator, Hyatt recommended
an APF of 50 for the respirator class as a whole.
    The 1980 ANSI respirator standard listed an APF of 100 for full
facepiece air-purifying respirators with DFM filters (Ex. 7-3). ANSI
increased the APF for this respirator class from 50 to 100 because the
poorly performing respirator in Hyatt's study was no longer in
production. Using the 1976 LANL quantitative fit testing results, the
1980 ANSI standard increased this APF to a maximum of 1,000 when the
respirator used HEPA filters and respirator users received quantitative
fit testing (Ex. 7-3).
    Based on Hyatt's 1976 data, the 1987 NIOSH RDL recommended that
this respirator class receive an APF of 50 when equipped with a HEPA
filter. However, the RDL gave these respirators an APF of 10 when using
DFM filters. NIOSH gave these respirators an APF of 10 when equipped
with DFM filters because testing that it conducted showed that the
filters had relatively low efficiency.
    The 1992 ANSI respirator standard retained the 1980 ANSI standard's
APF of 100 for full facepiece air-purifying respirators, but required
that respirator users perform quantitative fit testing and achieve a
minimum fit factor of 1,000 prior to using the respirators. QNFTs were
necessary because no QLFTs could achieve a fit factor of 1,000. The
ANSI standard kept this APF because the ANSI committee found, as it did
in 1980, that no WPF or SWPF studies had been performed for this
respirator class.
    The following table summarizes the previous APFs assigned to full
facepiece air-purifying respirators.

----------------------------------------------------------------------------------------------------------------
                                                                        APFs
  Fully facepiece air-purifying   ------------------------------------------------------------------------------
           respirators                                                                                1992 ANSI
                                        LANL (1976)       1980 ANSI standard     NIOSH RDL (1987)      standard
----------------------------------------------------------------------------------------------------------------
All respirators in the class.....  50 (with HEPA         10 (with QLFT)......  10 (with DFM filter)          100
                                    filter).
                                                         100 maximum (with     50 (with HEPA         ...........
                                                          QNFT).                filter).
----------------------------------------------------------------------------------------------------------------

    In the proposal, OSHA also discussed a WPF study that Colton,
Johnston, Mullins, and Rhoe (Ex. 1-64-14) conducted in a lead smelter.
The respirator used in this study was a 3M 7800 full facepiece air-
purifying respirator equipped with HEPA filters. The authors found a
5th percentile protection factor of 95 for the sample, but concluded
that the respirator only provided reliable protection at a protection
factor of 50. In addition, a LANL SWPF study by Skaggs, Loibl, Carter,
and Hyatt (Ex. 1-38-3) measured the protection afforded by the MSA
Ultra Twin respirator with HEPA filters. The authors reported fit
factors with geometric means ranging from 1,000 to 5,300. However, 23
of the 60 measurements reported were less than 1,000, seven were less
than 100, and three were less than 50. Based on a careful review of
these studies, OSHA proposed an APF of 50 for full facepiece air-
purifying respirators.
    OSHA requested comment in question 7 of the proposal on
whether it should

limit full facepiece negative pressure respirators to an APF of 20 when
N95 filters are used. The NIOSH certification tests for 42 CFR part 84
filters are conducted using monodisperse aerosols of the most
penetrating particle size (0.3 [mu]m) delivered at a high flow rate of
85 liters per minute. Also, the 42 CFR part 84 certification standards
allow up to 5% filter leakage with an N95 filter. If this level of
leakage were to occur in the workplace, an APF of 20 would be
appropriate for a full facepiece respirator using N95 filters. However,
as several commenters noted (Exs. 9-16, 9-22, 9-23, 9-37, 10-6, 10-17,
10-27, 10-59, and 10-60), workplace filter penetration is always much
less than filter penetration estimated from certification testing.
Kenneth Bobetich of MSA (Ex. 9-37) stated that while 5% leakage is the
worst case, such leakage does not occur in the workplace. Compared to
the aerosols used in certification testing, workplace aerosols are not
monodisperse, are many times larger, and are delivered through the
filters at a lower flow rate. In addition, the 3M Company (Ex. 9-16)
cited studies performed by Janssen (Exs. 9-16-1-3 and 9-16-1-4) that
compared the performance of N95 and P100 filters made by two
manufacturers and used during grinding operations in a steel plant.
Workplace performance of both filters was equivalent statistically, and
the study showed that N95 filter performance was adequate under these
conditions. Lisa Brosseau of the University of Minnesota (Ex. 10-59)
stated that it was entirely inappropriate for OSHA to consider a 5%
leakage effect for N95 filters because such leakage would only occur
when the aerosol is monodisperse and of a small size, conditions that
she said are unlikely to occur in most workplaces.
    Bill Kojola of the AFL-CIO (Ex. 9-27), Pete Stafford of the
Building Construction Trades Department of the AFL-CIO (Ex. 9-29), and
Michael Watson of the International Brotherhood of Teamsters (Ex. 9-7)
supported limiting the APF for full facepieces to 20 when N95 filters
are used. Watson stated that if OSHA gave these respirators an APF
higher than 20, employees would likely be exposed to hazardous levels
of workplace contaminants. Kojola stated further that OSHA should take
into account both sources of leakage (filter and faceseal), and lower
the APF accordingly. However, neither Watson nor Kojola provided any
evidence to support these misgivings about the performance of these
respirators.
    NIOSH (Ex. 9-13) recommended that OSHA consider the limitations of
the filter, but did not have any WPF or SWPF data on the performance of
full facepiece respirators certified under 42 CFR part 84 using N, R,
or P95 filters. NIOSH stated that because the filters are tested at the
most penetrating particle size, filter efficiency in the workplace
should exceed certification efficiency. However, NIOSH noted that some
workplace tasks, such as welding and grinding, may result in high
leakage rates through the N95 filter because the tasks produce fine or
ultra fine particles.
    Loraine Krupa-Greshman of the American Chemistry Council (Ex. 10-
25) stated that OSHA could not justify using a simplistic, generalized
treatment of N95 filter efficiency to limit the APF to 20. She noted
that using N95 or N100 filters is a matter of professional judgment,
based on the type and concentration of the contaminant. Frank White of
ORC Worldwide (Ex. 10-27) stated that reducing the APF to 20 was
unnecessary because protection factors and filter performance need to
be considered separately as part of the respirator selection process.
Ted Steichen of the American Petroleum Institute (API) (Ex. 9-23)
mentioned that API believes that OSHA should further evaluate the data
before assigning, based on worst-case assumptions, an APF of 20 to
these respirators. Thomas O'Connor of the National Grain & Feed
Association (Ex. 10-13) commented that he was not aware of any
scientific information that refuted assigning an APF of 50 to full
facepiece respirators or justified lowering the APF for N95 filters to
20. He supported retaining the proposed APF of 50 for this class of
respirators. Sheldon Coleman of the Hanford Site Respiratory Protection
Committee (Ex. 10-40) stated that, based on fit testing data, an APF of
50 for these respirators already is conservative.
    OSHA agrees with these commenters that full facepiece respirators
with N95 filters provide sufficient protection to maintain an APF of
50, and Table 1 of the final standard reflects this decision. Any
effect of filter penetration on respiratory protection is best
addressed during respirator selection, which also is the case for half
masks and other respirator classes using particulate filters. In rare
cases, when workplace exposures consist of a large percentage of
particles of the most penetrating size, this information must be taken
into account by the employer when selecting the appropriate class of
particulate filter for any respirator, not just for full facepieces.
    Summary and conclusions. In the proposal, OSHA asked for any
additional studies of full facepiece air-purifying respirators, but
none was submitted. After carefully evaluating the original studies
reviewed in the proposal, the Agency is setting an APF of 50 for full
facepiece air-purifying respirators. The final APF agrees with the
conclusion of Colton, Johnston, Mullins, and Rhoe (Ex. 1-64-14) cited
earlier in this discussion that this class of respirators provides
reliable protection at an APF of 50. Importantly, an APF of 50
corresponds with the APF previously assigned to full facepiece air-
purifying respirators by OSHA in its substance-specific standards, and
by NIOSH in its 1987 RDL. Therefore, OSHA is assigning an APF of 50 to
full facepiece air-purifying respirators based on: the results of WPF
and SWPF studies (which used N95 filters at moderate to high
contaminant levels); The APFs given previously to this respirator class
by NIOSH and ANSI; comments in the record indicating that N95 filters
function effectively under the workplace exposure conditions in which
they are used; and years of experience showing that these respirators,
when equipped with an N95 filter, are safe when used in the manner
prescribed by OSHA's respiratory protection standards. However, as with
any respirator, if a full facepiece air-purifying respirator is
unsuitable for the exposure conditions, paragraph (d)(1) of OSHA's
Respiratory Protection Standard requires that employers select a
respirator that will protect employees from the exposure hazards.
4. APF for Powered Air-Purifying Respirators (PAPRs)
    Half mask tight-fitting PAPRs. In the proposal, OSHA assigned an
APF of 50 to tight-fitting half mask PAPRs (68 FR 34098 and 34115)
based on the 1987 NIOSH RDL and the Z88.2-1992 ANSI respirator
standard. In arriving at a proposed APF of 50 for these respirators,
the Agency relied heavily on the WPF study conducted by Lenhart and
Campbell (Ex. 1-64-42), instead of the WPF study performed by Myers and
Peach (Ex. 1-64-46) and the SWPF studies of Skaggs et al. (Ex. 1-38-3)
and da Roza et al. (Ex. 1-64-94). In explaining its position, OSHA
stated:

    [The Lenhart and Campbell] study was well controlled and
collected data under actual workplace conditions; these conditions
ensure that the results are reliable and represent the protection
employees likely would receive under conditions of normal respirator
use. The Agency did not consider the Myers and Peach WPF study * * *
for this purpose because of problems involving filter assembly
leakage and poor facepiece fit reported by the authors;
consequently, the abnormally high levels of silica measured inside
the mask would most likely underestimate the true protection

afforded by the respirator. The two SWPF studies * * * reported much
higher geometric mean protection factors than did the WPF study
performed by Lenhart and Campbell. However, OSHA believes that the
higher protection factors reported for these SWPF studies are
consistent with the proposed APF of 50 based on data obtained for
this respirator class in the Lenhart and Campbell WPF study because
SWPF studies typically report significantly higher protection
factors than WPF studies of the same respirator. (68 FR 34098.)

    During this rulemaking, OSHA received no substantive comments or
other information regarding the proposed APF of 50 for these
respirators. Nevertheless, OSHA believes that the existing WPF and SWPF
studies on this class proved adequate support for OSHA's conclusion
that an APF of 50 is an appropriate level to predict the protection
capabilities of this class of respirators.
    Full facepiece PAPRs and PAPRs with hoods or helmets. In the
proposal, OSHA assigned an APF of 1,000 to tight-fitting full facepiece
PAPRs (68 FR 34099). In support of the proposed APF, OSHA cited a WPF
study by Colton and Mullins that found a corrected 5th percentile
protection factor of 1,335 for these respirators. OSHA received no
substantive comments or other information regarding the proposed APF of
1,000 for these respirators. However, the ANSI Z88.2-1992 respirator
standard and the 2004 draft revision to the ANSI standard both assign
an APF of 1,000 to this respirator class. Based on its review of these
consensus standards and the existing WPF research literature (see Exs.
1-64-12 and 1-64-40), and SWPF research studies (Ex. 3-4), OSHA
concludes that this respirator class warrants an APF of 1,000.
    In proposing an APF of 1,000 for PAPRs with helmets or hoods, the
Agency stated in footnote 4 of proposed Table 1 that ``only helmet/hood
respirators that ensure the maintenance of a positive pressure inside
the facepiece during use, consistent with performance at a level of
protection of 1,000 or greater, receive an APF of 1,000'' and that
``[a]ll other helmet/hood respirators are treated as loose-fitting
facepiece respirators and receive an APF of 25.'' (See 68 FR 34115.)
OSHA proposed this condition because available WPF and SWPF studies
found that some of these hood/helmet respirators achieved protection
factors well below 1,000 (Exs. 3-4 and 3-5). Under the proposed
condition, the burden of conducting any testing likely would fall on
respirator manufacturers, but the employer would be responsible for
selecting a properly tested respirator.
    According to James Johnson of LLNL, simple and effective equipment
and procedures are available for detecting leaks in these respirators.
In this regard, Johnson noted that LLNL developed equipment that
monitors and records positive pressure in these respirators using a
commercially available device. As he stated at the hearing:

    [T]his is the one we chose, a data logging micro manometer, the
TSI-DP Calc, with a range of -5 to +15 inches of water gauge, and
data recording intervals of one second and longer were chosen. * * *
We plan on using this technique periodically to monitor actual high-
contamination work activities to assure this PAPR maintains a
positive pressure. (Ex. 16-9-1.)

    A number of commenters provided additional support for using
positive pressure inside the facepiece as the criterion for protection.
For example, Rick Givens of the Atlanta, GA Utilities Department stated
that ``the maintenance of positive pressure is an appropriate method
for distinguishing high-performing hood/helmet respirators from
others'' (Ex. 10-2), while Sheldon Coleman of the Hanford, Washington
DOE site asserted:

    In the last three years, our program has used approximately
10,000 PAPR hoods. We have conducted some limited fit testing using
particulate fit testers (although the hood manufacturer does not
recommend using a particulate tester due to the extensive dead space
in the hood). All of our information suggests that an APF of 1,000
is appropriate for a PAPR hood that maintains positive pressure
inside of the hood. (Ex. 10-40.)

    Several commenters took exception to the positive pressure
criterion. Craig Colton of 3M stated that ``3M disagrees with OSHA's
proposed requirement that hoods and helmets demonstrate that they
maintain positive pressure at all times of use to receive an APF of
1,000'' (Tr. at 390). In this regard, Colton argued that the recent
study conducted on PAPRs with hoods/helmets by ORC and LLNL showed that
every respirator tested in the study ``had two or more brief negative
pressure spikes within the respiratory inlet covering. Under the
current proposal, all of these respirators, except the poorest
performing supplied-air respirator would have received an APF of 25,
even though the 5th percentile SWPFs found in the study ranged from
86,000 to 250,000'' (Tr. at 391). Colton then added, ``This study
indicates that pressure within the respiratory inlet covering is only
one of a complex set of factors that determine the protection provided
by PAPRs and supplied-air respirators, and should not be considered by
itself'' (Tr. at 391). John P. Farris of Safe Bridge Consultants echoed
this concern (Exs. 9-11 and 10-32).
    Other comments focused either on the need for a protocol to
determine if the respirators could perform at an APF level of 1,000, or
on design characteristics that would permit respirator users to select
appropriate respirators. In advocating the testing approach, Stephan
Graham of the U.S. Army Center for Health Promotion and Preventative
Medicine noted that respirators that have high APFs should receive
credit for their design and performance. Graham recommended that
manufacturers test their hooded and helmeted respirators, and set the
maximum APF (to a maximum of 1,000) based on the results (Ex. 9-42-1).
The 3M Company stated that if OSHA retains a testing requirement in the
final rule, it must specify the testing conditions. The 3M Company
recommended testing at a work rate of 40 liters per minute, ensuring
that pressure inside the hood or helmet is maintained at a minimum
level of one atmosphere at this work rate, measuring this pressure at
the flow rate recommended by the manufacturer, and maintaining the
maximum static pressure inside the hood or helmet at 38 mm of water
pressure (Ex. 18-7). Similarly, Jay Parker of the Bullard Co. stated
that ``without oversight and guidance, testing performed may not
achieve such goals. This may lead to the use of respirators and an APF
of 1,000 that actually should not be used at that level because the
testing performed was not really capable of ensuring that level of
performance'' (Tr. at 492).
    ORC Worldwide stated that ``the approach proposed by OSHA would
hold hood/helmet or loose-fitting facepiece PAPRs and SARs to a higher
standard than that required of other respirator classes, based simply
on the results of one model'' (Ex. 10-27), a point made as well by
Alice E. Till of the Pharmaceutical Research and Manufacturers
Association (PhRMA) (Ex. 9-24). Nevertheless, ORC concluded that,
``[s]hould OSHA retain this requirement, the final rule should clearly
specify acceptable testing criteria to which respirator manufacturers
must conform'' (Ex. 10-27). PhRMA believed that OSHA should consider
the proposed APF table to be an interim step in a transition toward the
development of a certification protocol by NIOSH that provides APFs for
each respirator model (Ex. 9-24). Thomas Nelson of NIHS, Inc. agreed,
stating, ``Specific test conditions and performance criteria must be
identified'' (Ex. 10-17).

    NIOSH provided the following information that addressed the
concerns of these commenters:

    Respirator models should not be assigned to the higher APF level
following promulgation of the proposed APF rule unless the
respirator manufacturer provides evidence that testing of that model
demonstrates performance at the higher APF level. A standard test
protocol is needed to assure reliable and reproducible results when
determining if a hood/helmet PAPR * * * can consistently achieve a
protection factor of 1000. NIOSH will assist in developing this
protocol. With implementation of new NIOSH certification criteria,
every respirator model could be evaluated using this protocol as a
condition of certification to assure overall performance consistent
with the established APF. Thus, NIOSH will assure that approved
respirators are capable of providing this assigned level of
protection so that employers have appropriate guidance and APF
values when selecting respirators for their workers. (Ex. 16-4.)

    Proponents of using design criteria, instead of testing, to assess
the protection afforded by these respirators recommended that poorer
performing respirators should be identifiable by either their
appearance or technical specifications. For example, John Ferris of
Safe Bridge Consultants, stated:

    In my experience, the most important factor in achieving
workplace protection factors of 1,000 or greater with these devices
is the ability to tuck the inner bib (or shroud) into the outer work
garment with the outer shroud placed over the shoulders on the
outside of the garment. I support the use of a 1000-fold APF for
helmet hood PAPRs without the footnote. (Ex. 9-11.)

    Robert Barr of Alcoa noted that design flaws need to be identified,