Federal Register: October 30, 2009 (Volume 74, Number 209)
DOCID: fr30oc09-24 FR Doc E9-26008
DEPARTMENT OF HEALTH AND HUMAN SERVICES
Health and Human Services Department
CFR Citation: 42 CFR Part 84
RIN ID: RIN 0920-AA33
NOTICE: PROPOSED RULES
DOCID: fr30oc09-24
DOCUMENT ACTION: Notice of proposed rulemaking.
SUBJECT CATEGORY:
Total Inward Leakage Requirements for Respirators
DATES: CDC invites comments on this proposed rule from interested parties. Comments must be received by December 29, 2009.
DOCUMENT SUMMARY:
The Centers for Disease Control and Prevention (``CDC'') proposes to establish total inward leakage (TIL) requirements for half mask airpurifying particulate respirators approved by the National Institute for Occupational Safety and Health (``NIOSH'') of CDC. The proposed new requirements specify TIL minimum performance requirements and testing to be conducted by NIOSH and respirator manufacturers to demonstrate that these respirators, when selected and used correctly, provide effective respiratory protection to intended users against toxic dusts, mists, fumes, fibers, and biological and infectious aerosols (e.g. influenza A(H5N1), severe acute respiratory syndrome (SARS) coronavirus, and Mycobacterium tuberculosis).
SUMMARY:
Total Inward Leakage Requirements for Respirators
SUPPLEMENTAL INFORMATION
[[Page 56142]]
I. Public Participation
Interested persons or organizations are invited to participate in this rulemaking by submitting written views, arguments,
recommendations, and data. Comments are invited on any topic related to this proposal.
Comments submitted by email or mail should be addressed to the
``NIOSH Docket Officer,'' titled ``NIOSH Docket
All comments submitted will be available for examination in the
rule docket (a publicly available repository of the documents
associated with the rulemaking) both before and after the closing date
for comments. A complete electronic docket containing all comments
submitted will be available at: http://www.cdc.gov/niosh/docket/
NIOSHdocket0137.html and comments will be available in writing by
request. NIOSH includes all comments received without change in the docket, including any personal information provided.
II. Background
A. Introduction
Under 42 CFR part 84, ``Approval of Respiratory Protective Devices'' (``Part 84'') NIOSH approves respirators used by workers in mines and other workplaces for protection against hazardous atmospheres. The Mine Safety and Health Administration (``MSHA'') and the Occupational Safety and Health Administration (``OSHA'') require U.S. employers to supply NIOSHapproved respirators to their employees whenever the employer requires the use of respirators. In addition, MSHA coapproves with NIOSH all respirators used in mine emergencies and mine rescue.
Testing, quality control, and other requirements under Part 84 are
intended to ensure that respirators supplied to U.S. workers provide
effective protection when properly employed within a complete
respiratory protection program, as specified under MSHA and OSHA
regulations. NIOSH requirements governing approval of the type of
respirators covered by this proposed rule are specified in 42 CFR part
84, principally under Subpart KNonPowered AirPurifying Particulate
Respirators. These were last updated in 1995 (60 FR 3033630404). At
that time, NIOSH proposed but ultimately omitted requirements for
testing the performance of these respirators with respect to TIL \1\ to
allow for further research on the effectiveness of TIL testing methods.\2\
\1\ TIL is the combination of contaminated air leaked through
various potential sources including the facepiecetoface seal, exhalation valves (if any), and gaskets (if any) and any
contaminants that have penetrated the filter.
\2\ The isoamyl acetate or American National Standards Institute (ANSI)/OSHA accepted fit tests.
The performance of the facepiecetoface seal and other potential sources of leakage for this type of respirator are important because these determine how much unfiltered contaminated air the worker might inhale. The facepiecetoface seal leakage can be substantial in the case of a poorly fitting respirator.
Effective fit testing technology and procedures now exist to assure that respirators approved by NIOSH under Subpart K of Part 84 have adequately performing facepiecetoface seals and sufficiently control TIL. The purpose of this rulemaking is to promulgate general requirements for such TIL testing and performance. The draft specific technical procedures to be applied under such requirements can be found at http://www.cdc.gov/niosh/docket/NIOSHdocket0137.html. When finalized, the procedure will be detailed with all other NIOSH respirator certification testing procedures on the NIOSH Web page at http://www.cdc.gov/niosh/npptl/stps/respirator_testing.htm. B. Background and Significance
Employers rely upon NIOSHapproved respirators to protect their employees from airborne toxic contaminants and oxygendeficient environments. More than 3.3 million private sector employees in the United States wear respirators for certain work tasks.
Workers depend on respirators to protect them from asphyxiation or airborne contaminants that are known or suspected to cause acute and chronic health effects, such as heavy metal poisoning, acid burns, chronic obstructive pulmonary disease, silicosis, neurological disorders, and cancer.
As the last line of protection for workers, respirators must be designed and manufactured to perform reliably and tested for compliance to a specified minimum level of performance. The worker might not be able to detect ineffective performance of the respirator prior to the toxic exposure, upon which it might be too late to avoid serious injury or death.
Respirator manufacturers and NIOSH have critical roles in assuring employers, other purchasers of respirators, and workers that their respirators will provide the protection that is implied by their NIOSH certification. This rulemaking, which has been identified as a priority among the policymaking needs of the NIOSH respirator certification program by respirator manufacturers, employers, and other stakeholders of the program, is intended to strengthen this assurance.
C. Need for Rulemaking
This rulemaking would establish TIL performance requirements and testing of halfmask, airpurifying particulate respirators currently approved under the requirements of Part 84 Subpart KNonPowered Air Purifying Particulate Respirators. These respirators are used by two million U.S. workers: For example, they are used in health care settings by caregivers and staff to patients with tuberculosis and other respiratory infections; in foundries, chemical manufacturing, and other production facilities with potentially hazardous aerosol exposures such as metals, coal, plastics, fibers, nano materials, and silica; and at construction and landscaping sites where workers are exposed to wood, silica, and other dusts from the grounds and building materials. These respirators are also stockpiled in large caches for deployment to public safety, health care, and other service personnel in the advent of an influenza pandemic.
NIOSH evaluation of the TIL performance of these respirators would
provide increased assurance to respirator purchasers and users that
NIOSHapproved respirators can be expected to effectively protect the
user against particulate contaminants, when properly donned and used.
NIOSH has conducted benchmark testing of 101 respirator models
currently on the market, using a testing regimen similar to that being
proposed in this rulemaking, to assess their TIL performance.
Approximately 30 percent of this class of respirators have facepiece
seals that did not perform adequately to achieve a fit factor of 100
(limiting total inward leakage to no more than 1 percent), as specified
by OSHA,\3\ for substantial numbers of the human subjects donning them for
[[Page 56143]]
benchmark testing. This finding is supported by published
research.4 5
\3\ See 29 CFR 1910.134 (f)(7).
\4\ Coffey C, Lawrence R, Campbell D, Zhuang Z, Calvert C,
Jensen P. Fitting Characteristics of Eighteen N95 Filtering Facepiece Respirators. JOEH. 2004;1: 262271.
\5\ Lawrence R, Duling M, Calvert C, and Coffey C. Comparison of
Performance of Three Different Types of Respiratory Protection Devices. JOEH. 2006;3:465474.
There are three implications of this finding from benchmark testing, which define the need for this rulemaking. One, when an employer purchases one of these respirator models with poor TIL performance for use within a complete respirator program, as specified by OSHA and MSHA, fittesting of the employees should reveal that a substantial proportion of the employees do not achieve an adequate fit. This presumably compels the employer to purchase other respirators and conduct additional fittesting on employees, continuing such purchases and fit testing until respirators are identified, through trial and error, that provide all employees with adequately fitting respirators.
This process of identifying respirators that provide an adequate fit to each employee would be streamlined through NIOSH evaluation of TIL performance as proposed in this rulemaking, using panels of test subjects representative of intended users of a particular respirator model and size. The employee is more likely to achieve a good fit from a respirator make that has been demonstrated through testing to achieve a specified minimum level of performance in this respect.
The second implication applies to situations in which these poorly performing respirators are being used by employees and other individuals without the benefit of a complete respirator program that includes fit testing. A recent NIOSH/Bureau of Labor Statistics (BLS) survey of respirator use among U.S. workers found that 40 percent of employers are not selecting respirators for their employees based on fit testing.\6\ Selfemployed workers in industries such as construction may be even less likely to perform fit testing. \6\ NIOSH/BLS [2003]. Respirator usage in private sector firms, 2001 (PDF only 1,118 KB (278 pages)). Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health.
For these employee and worker populations, the poor fit might not be recognized, increasing the likelihood that substantial numbers of these respirator users are not being adequately protected from their hazardous exposures. While the only way to ensure that a particular respirator make and size performs adequately for a user is through fit testing of that user, NIOSH testing and evaluation of TIL performance would increase the likelihood that these workers who lack fit testing will be protected, by obtaining respirators that are demonstrated to generally provide a good fit to intended users when worn properly.
The third implication applies to the stockpiling of respirators for use in case of an influenza pandemic. During a disease outbreak, such respirators might be deployed without a respirator program and without fit testing. Currently, the selection of NIOSH approved respirators provides no assurance that stockpiled respirators are likely to provide adequate protection to the health care, public safety, and other personnel who might use them without a respirator program and fit testing. The availability of NIOSH certification with respect to TIL performance would increase the likelihood that such users would obtain an adequate fit and protection, even though it could not provide the same level of assurance as is obtained from fit testing of each individual for the selection of respirators.
In summary, revising Part 84 to incorporate minimum performance requirements governing TIL is a necessary step to ensure that NIOSH approved halfmask air purifying particulate respirators have facepiecetoface and other seals that perform adequately to provide effective protection to most intended users. While this certification testing will not substitute for individual fit testing, respirator training, and other components of a complete respiratory protection program critical to worker protection, it will substantially improve the current circumstances by approving only respirators that demonstrate the ability to meet minimum specified performance requirements and are likely to provide adequate protection to most intended users when properly fitted and worn.
D. Public Meetings for Discussion and for Comment
NIOSH held public meetings to discuss underlying issues and
technical matters addressed in this proposed rule on August 25, 2004,
at the Key Bridge Marriott, Arlington, VA, and June 26, 2007, at The
Embassy Suites Pittsburgh International Airport, Coraopolis,
Pennsylvania.\7\ Official transcripts of the meetings, as well as
public comments submitted subsequently, are available in Docket
One issue of concern raised in response to NIOSH presentations was that the NIOSH rule would prevent respirator manufacturers from producing models targeted to specific demographic subpopulations, such as women, for example. The current proposal would not impose any such limitation. NIOSH will construct test subject panels for the certification testing that represent the population targeted by the manufacturer, as described in the manufacturer's user instructions.
Another concern raised by commenters is that this rulemaking would shift responsibility for the fit achieved by employees from the employer, who is required to conduct fit testing under OSHA and MSHA regulations, to the respirator manufacturer. No such substitution is intended or effected by the rulemaking. As discussed above, NIOSH would require that manufacturers produce respirators that have effective face seals, such that they can be expected generally to fit intended users and control TIL adequately when the respirators are properly fit tested, donned, and used. This general assurance does not replace individual fit testing to be conducted by employers, which ensures that each individual employee obtains an effective fit, as required by OSHA and MSHA.
NIOSH already requires adequate TIL performance for other types of respirators under Part 84. NIOSH omitted such requirements for the category of respirator covered in this rulemaking only because of testing limitations that existed in 1995 when Part 84 was established.
NIOSH received concerns regarding the use of various testing technology and methods to evaluate TIL. The technology is identical to that in common use for measuring respirator fit and is accepted by OSHA.\8\
\8\ 29 CFR 1910.134, Appendix A, Part I, C, 3.
Comments were received questioning the representativeness of the
test panel with respect to the population of respirator users. The test
panel was developed by NIOSH to replace a panel developed decades ago
by Los Alamos National Laboratory using military personnel. The new
panel has been the subject of publications and multiple reviews, including a review by the
[[Page 56144]]
Institute of Medicine.9 10 11 It is documented in testing
and agreed by reviewers that the proposed panel represents a
substantial improvement over its predecessor panel and should be implemented.
\9\ Zhuang Z, Bradtmiller B, and Shaffer R.E. New Respirator Fit
Test Panels Representing the Current U.S. Civilian Workforce.
Journal of Occupational and Environmental Hygiene 2007;4: 647659.
\10\ Zhuang Z, Groce D, Ahlers H, Iskander W, Landsittle D,
Guffey S, Benson S, Viscusi D, Shaffer R. Correlation between
Respirator Fit and Respirator Fit Test Panel Cells by Respirator
Size. Journal of Occupational and Environmental Hygiene. 2008;5: 617628.
\11\ Institute of Medicine. Assessment of the NIOSH Headand
Face Anthropometric Survey of U.S. Respirator Users. The National Academies Press, Washington, DC (2007).
Commenters also questioned the number of test subjects and the pass/fail criteria. NIOSH has changed the pass/fail criteria and the number of test subjects as a result of these comments. A full technical discussion of the statistical basis for the proposed standards described below is provided in a paper titled ``Statistical Basis for TIL Testing'' in the NIOSH Docket for this rulemaking posted at: http:/ /www.cdc.gov/niosh/docket/NIOSHdocket0137.html. The maximum allowable leakage is now equivalent to the fit test criteria required by OSHA for this type of respirator.\12\
\12\ 29 CFR 1910.134(f)(7).
These concerns have been given consideration in the design of this proposed rule and will be considered further in the development of testing procedures to be implemented under a final rule. NIOSH encourages interested parties to submit any technical concerns along these lines, as well as policy concerns, in response to this proposed rule.
NIOSH will convene a public meeting to provide stakeholders an opportunity to comment orally on this rulemaking during the comment period. The meeting will be in the vicinity of Washington DC and will be announced in a separate notice in the Federal Register. This meeting will also be available through remote access capabilities. Participants will be able to simultaneously listen and view presentations over the Internet, as well as comment.
III. Summary of Proposed Rule
This proposed rule would establish new TIL requirements for half
mask airpurifying particulate respirators approved by NIOSH, or NIOSH
and MSHA, under 42 CFR part 84Approval of Respiratory Protective
Devices. These provisions would be added to Subpart K. The following is
a sectionbysection summary which describes and explains the
provisions of the rule. The public is invited to provide comment on any
aspect of the proposed rule. The complete regulatory text for this
proposed rule is provided in the last section of this notice. For the
convenience of readers, the regulatory text presents the amended
sections in their entirety, including the proposed new and revised
paragraphs and those that would remain unrevised under the amended sections.
Subpart K
Section 84.175 HalfMask Facepieces, Full Facepieces, Hoods, Helmets,
and Mouthpieces; Fit and Total Inward Leakage (TIL); Minimum Requirements
This section includes a variety of general requirements governing the fit and functionality of the various designs of nonpowered air purifying particulate respirators. NIOSH proposes to amend this section to incorporate TIL standards and a general specification of testing requirements. Paragraphs in this section that are not discussed below are current provisions that NIOSH is not proposing to amend. A. HalfMask Respirators Designed for Specific Segments of the Population
Paragraph (a)(3) is new. It would allow applicants to seek approval for halfmask respirators designed to fit a specific segment of the population, such as ``women'' or persons within specific dimensional limits. Currently, respirators must be designed to fit the population broadly, either by providing one size that fits diverse facial shapes and sizes or by providing multiple sizes. It is advantageous to employers and other respirator purchasers to supply a respirator that fits the population broadly because it simplifies their selection and purchasing of such equipment. It also increases the likelihood that the majority of workers and other respirator users will obtain respirators that fit. However, in connection with public discussions regarding the concepts underlying TIL standards and testing, several respirator manufacturers have advocated that they have the option of producing respirators designed to fit particular subpopulations, presumably to more reliably achieve a fit for certain face shapes that might not obtain a good fit from generallytargeted designs. Furthermore, while NIOSH benchmark testing and other research have indicated that many respirators do not actually provide a good fit to substantial segments of the population, it is possible that some of these respirators are well designed to fit particular subpopulations.
NIOSH accepts the proposition that in some cases it might be effective to design respirators to fit specific subpopulations that share common facial characteristics, resulting in better TIL performance. Since this approach would rely on purchasers recognizing an appropriate match, NIOSH has specified that the membership of the subpopulation, as described, must be somehow identified. Thus, for example, sex is clear. However, it is unclear to NIOSH whether there are other demographic classifications or descriptors for subpopulations that could be both reliably interpreted by users and reliably determinative in terms of respirator fit. Users must be provided sufficient information to permit them to selfidentify. They might not effectively selfidentify to match a manufacturer's intentions if provided only vague general descriptions of intended facial shapes or characteristics.
A new paragraph (g) would require that any part of a respirator that would have to be removed to conduct a user seal check must be replaceable without disturbing the fit of the respirator. This is a current requirement for other types of respirators and is essential to assuring the validity of the seal check.
Paragraph (h) is also new. It would require the user instructions
of a halfmask respirator to specify the intended users of the
respirator, by facial size, if applicable, and by other descriptive
information as might be necessary for respirators designed for specific
subpopulations, as explained above. This information would be relied
upon by purchasers and users and by NIOSH in conducting TIL testing, as discussed below.
B. HalfMask Respirator TIL Testing Requirements
General Discussion
Subsection (i) is new. It proposes the general procedures,
requirements, and performance standards for TIL of nonpowered half
mask airpurifying particulate respirators. The standards have been
designed statistically to identify and pass with high accuracy (greater
than 90 percent probability) those respirators that provide adequate
TIL performance to the large majority of intended users (in the range
of 80 to 90 percent of intended users) while failing with near
certainty (greater than 99 percent probability) those respirators that
do not provide adequate TIL performance to a majority (50 percent or
more) of intended users. Adequate TIL performance is a TIL value of 1.0,
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equivalent to a fit factor of 100, which is the level of performance
for these respirators specified by OSHA.\13\ The number of test
subjects proposed for the testing has been limited to maintain
reasonably modest testing costs for NIOSH and respirator manufacturers
while achieving a representative crosssection of the intended user
population and providing sufficient ``statistical power'' to evaluate
TIL performance accurately. A full technical discussion of the
statistical basis for the proposed standards described below is
provided in a paper titled ``Statistical Basis for TIL Testing'' in the
NIOSH Docket for this rulemaking posted at: http://www.cdc.gov/niosh/
docket/NIOSHdocket0137.html. NIOSH requests public comment concerning
the judgments inherent to these proposed standards, as well as comment on the supporting statistical analysis referenced here.
\13\ See 29 CFR 1910.134(f)(7).
NIOSH invites public comment on the proposed standards specified in this subsection. There are several critical factors that the public should consider in providing such comments:
1. What percentage of the intended user population should be able to achieve adequate TIL performance for the respirator to be approved by NIOSH? NIOSH has proposed that 75 percent or higher should be able to achieve such performance. This performance level is based on the design and statistical considerations presented above in this General Discussion section; essentially, using this 75 percent testing parameter would provide strong assurance (90 percent probability) that testing identifies for approval respirators fitting the large majority80 to 90 percentof intended users, while rejecting with near certainty (99 percent probability) respirators that fit only a minorityless than 50 percentof intended users.
2. As the percentage of the intended user population capable of achieving adequate TIL performance from a respirator declines, at what point, if any, should NIOSH set the limit to be nearly certain (e.g., 99 percent or higher probability) that the respirator would not be approved? NIOSH has proposed that a respirator should be rejected with near certainty if it does not provide adequate TIL performance to at least a majority (50 percent or greater) of intended users. NIOSH believes this is a reasonable standard for defining the performance of a poorly fitting respirator that should not be approved.
3. How many test subjects should be included in the testing, considering the fact that testing accuracy increases with the number of test subjects, but that the cost of testing also increases with the number of test subjects? Do the numbers of subjects proposed by NIOSH (15 to 35 test subjects, as specified under Sec. 84.175(i)(4)) reflect an appropriate balance between limiting manufacturer testing costs and providing sufficiently accurate results? What level of testing cost is supportable, in the view of manufacturers? Would manufacturers prefer a higher numbers of test subjects and associated higher costs, to reduce further the likelihood that a respirator with adequate TIL performance is denied by chance?
Discussion of Specific Provisions
Paragraph (i)(1) specifies that NIOSH will apply solely the user instruction information describing the intended users of a respirator to select an appropriate panel of TIL test subjects. Thus, NIOSH will be interpreting the user instructions with the same limitations as a purchaser or intended user.
This provision would have no practical effect in the case of a respirator designed to fit the general population, either through one size that fits all users or a comprehensive set of differing sizes. In such a case, the respirator would be tested against the NIOSH testing panel, which respirator manufacturers can replicate in their pre application TIL testing to ensure that their respirator is designed and manufactured to achieve an adequate fit on the testing panel to meet the NIOSH TIL standard. On the other hand, this provision limiting NIOSH to the information provided in the user instructions could be important in the case of a respirator designed for use by a specific subpopulation. As a consequence, if the applicant were to have selected test subjects for preapplication TIL testing using additional criteria or distinguishing factors not specified in the user instructions, it is possible the applicant would obtain a panel of test subjects substantially different from that selected by NIOSH for its TIL testing. A substantial difference in test panels could produce different testing results and potentially result in the failure of the respirator to pass the TIL performance standard.
Paragraph (i)(1) also specifies the number or minimum number of representative test subjects to be used in TIL testing; 35 for a respirator intended to fit the general population and a minimum of 15 for a respirator intended to fit one or more specific subpopulations. These numbers are proposed in combination with the performance standards specified in paragraph (i)(4) to provide a sufficiently accurate measure of a respirator's TIL performance for at least 75 percent of intended users while minimizing the chance of either approving a respirator that did not achieve adequate TIL performance for at least 50 percent of intended users or of disapproving a respirator that only by chance failed to achieve the TIL performance standard for at least 75 percent of intended users. A full technical discussion of the statistical bases of these standards is provided in a paper titled ``Statistical Basis for TIL Testing'' posted at: http:// www.cdc.gov/niosh/docket/NIOSHdocket0137.html.
Paragraph (i)(2) specifies that test subjects will conduct a user seal check or other donning procedure prior to each test. This is appropriate practice for a worker donning this type of respirator, to ensure that it is positioned correctly on the face to provide an optimal facepiecetoface seal.
Paragraph (i)(3) specifies that the TIL test will be administered to each test subject up to three times, terminating testing either when a test has produced a TIL value of 1.0 percent or less or after the third test, whichever occurs first. The TIL value of 1.0 percent is equivalent to a fit factor of 100, which is the minimum acceptable fit factor for halfmask respirators specified by OSHA under 29 CFR 1910.134 (f)(7). The limit of administering the test up to three times to achieve this performance standard is integral to the statistical basis establishing the accuracy of the TIL testing, as discussed above and in technical detail in the paper ``Statistical Basis for TIL Testing'' posted at: http://www.cdc.gov/niosh/docket/ NIOSHdocket0137.html.
Paragraph (i)(4) provides the TIL performance standards for
approval of these respirators, differing under clauses (i) and (ii) to
account for the lower minimum number of test subjects (a minimum of 15
versus 35) that would be used to test a respirator intended to fit one
or more specific subpopulations under clause (ii). Given the lower
number of test subjects, a higher proportion of the test subjects (80
percent versus approximately 75%) would be required to achieve a TIL
value of 1.0 percent or less for the respirator to be approved. This
difference is statistically based in the decreasing reliability of an
individual test as the total number of test subjects declines. It is
discussed and illustrated in the paper ``Statistical Basis for TIL
Testing'' posted at: http://www.cdc.gov/niosh/docket/
NIOSHdocket0137.html. The proposed use of a minimum of 15 test subjects for respirators intended to
[[Page 56146]]
fit one or more subpopulations of users allows for the use of a larger
number of test subjects for subpopulations that are more diverse and
hence, require a more diverse panel of test subjects to provide
sufficiently comprehensive representation of facial dimensions.
Paragraph (i)(5) specifies that the probe would be located halfway between the wearer's nose and mouth for TIL testing of the respirator. This specification is consistent with the technology used for such testing and is necessary to ensure a reproducible determination of TIL.
Paragraph (i)(6) specifies the use of sodium chloride (table salt) as the challenge aerosol for TIL testing and specifies a particle size range of 0.02 to 0.06 micrometers within a concentration range of 1,500 to 3,000 particles/cm\3\. Sodium chloride is used because it is safe for the test subjects and has appropriate physical properties for the test. The particle size range represents the most penetrating particle sizes, producing an atmosphere that challenges the limits of the respirator's TIL performance. The concentration range allows for accurate measurement using the current technology available for TIL testing.
Paragraph (i)(7) specifies the sequence of exercises that comprise the TIL test. These are the standard, OSHArequired set of exercises to be used in fittesting these respirators. They provide for realistic respirator use conditions that challenge the respirator's TIL performance through typical work movements, postures, grimaces that can disturb the facepiecetoface seal, talking, and deep breathing to increase the negative pressure inside the facepiece.
Paragraph (i)(8) specifies that the test exercises will be performed using the OSHA protocol provisions specified at 29 CFR 1910.134 Appendix A, Part I.A.14(b). This protocol paragraph specifies the duration of each test exercise used in fit testing. Currently, OSHA requires each exercise be performed for one minute except for the grimace, which is performed for 15 seconds. By specifying this element of the OSHA protocol, NIOSH would ensure that NIOSH TIL testing remains consistent with OSHA fit testing requirements in this regard.
Paragraph (i)(9) specifies that the test subject will not adjust the facepiece position once the TIL test exercises begin, and that any such adjustment would void the test, requiring that it be repeated. This is current fittesting practice and is required by OSHA under 29 CFR 1910.134 Appendix A, Part I.A.14(b). The intent of this requirement is to realistically reflect the practices and conditions of workers when wearing respirators. A worker typically would adjust the facepiece if he sensed a poor facepiecetoface seal. However, a worker might not adjust the facepiece for many reasons, such as not sensing a poor facepiecetoface seal, or being engaged in a task that occupies both hands. Moreover, the need to adjust the facepiece periodically after donning the respirator indicates an undesirable TIL performance characteristic. For example, the need to make such adjustments during a work task would constitute a hazard if safe work practice requires that the worker's hands and/or attention be fully engaged in the work task.
Paragraph (i)(10) specifies how TIL is determined. TIL results are expressed as the percentage quantity of the ambient concentration of sodium chloride measured inside the respirator. For example, if the ambient concentration were 1000 particles/cm\3\ and the respirator reduced this concentration to 10 particles/cm\3\, then the TIL would be expressed as 1.0 percent, because the concentration inside the respirator facepiece was reduced to 1.0 percent of the ambient level. This is equivalent to a fit factor of 100, which is the inverse of the TIL and is calculated as the ratio of the ambient concentration over the concentration inside the respirator facepiece.
Paragraph (i)(11) specifies design and performance attributes of the instrumentation to be used to take measurements of TIL. These include the use of a condensation nuclei counter, the ability to measure sodium chloride challenge aerosol in the specified size range of 0.02 to 0.06 micrometers, and during measurement, responding linearly to changes in the aerosol concentration, within plus or minus five percent, over the ambient concentration range of 70 to 3,000 particles/cm\3\ and TIL <= 5.0 percent. These attributes are sufficient to meet the needs of TIL testing as proposed and to ensure that NIOSH and manufacturers use equivalent instrumentation.
Section 84.205 Facepiece Test; Minimum Requirements
This section specifies facepiece test requirements for chemical
cartridge respirators. Some of these respirators are designed as half
mask, combination chemical cartridge/particulate filtering (i.e., air
purifying) respirators. For such combination respirators, NIOSH
proposes applying the identical TIL test requirements as proposed under
Sec. 84.175 in this rulemaking for all halfmask airpurifying
particulate respirators. These TIL test requirements would be in
addition to the current facepiece test requirements already covered
under this section for chemical cartridge respirators. Paragraphs in
this section that are not discussed below are current provisions that NIOSH is not proposing to amend.
A. NonGermane Technical Revisions to General Provisions of Sec. 84.205
Paragraphs (c) and (d) would be revised, substituting the term ``user seal check'' for ``fit test'' to be consistent with current terminology in use.
Paragraph (d)(1) would be revised to reduce the specified ambient
concentration of isoamyl acetate vapor in the testing chamber from
1,000 to 500 parts per million (ppm) for testing full facepieces,
mouthpieces, hoods, and helmets. This represents current practice,
which the NIOSH respirator certification program instituted when NIOSH lowered the IDLH (Immediately Dangerous to Life or Health
concentration) for isoamyl acetate to 1,000 ppm.
B. Coverage of Combination HalfMask Chemical Cartridge/Particulate
Filtering Respirators by TIL Testing Requirements of Sec. 84.175
A new paragraph (e) would be added to require TIL testing under the
proposed provisions of Sec. 84.175(i) for all combination halfmask
chemical cartridge/particulate filtering respirators. The NIOSH
respirator certification program currently conducts qualitative testing
using isoamyl acetate vapor to evaluate the fit of chemical cartridge
respirators under Sec. 84.205, including these combination
respirators. The proposed TIL testing would ensure that the particulate
filtering protective capacity of these combination respirators is as
effective as the singlepurpose airpurifying respirators addressed by this rulemaking.
IV. Regulatory Assessment Requirements
A. Executive Order 12866
Under Executive Order 12866 (58 FR 51735, October 4, 1993), the
Agency must determine whether a regulatory action is ``significant''
and therefore subject to review by the Office of Management and Budget
(OMB) and the requirements of the executive order. Under section 3(f),
the order defines a ``significant regulatory action'' as an action that
is likely to result in a rule (1) Having an annual effect on the
economy of $100 million or more, or adversely and materially affecting a sector of the economy, productivity,
[[Page 56147]]
competition, jobs, the environment, public health or safety, or state,
local, or tribal governments or communities (also referred to as
``economically significant''); (2) creating serious inconsistency or
otherwise interfering with an action taken or planned by another
agency; (3) materially altering the budgetary impacts of entitlements,
grants, user fees, or loan programs or the rights and obligations of
recipients thereof; or (4) raising novel legal or policy issues arising
out of legal mandates, the President's priorities, or the principles set forth in this executive order.
This proposed rule is not considered economically significant, as defined in section 3(f)(1) of the executive order. However, this proposed rule is a ``significant regulatory action'' within the meaning of the executive order and has been reviewed by OMB.
For the leading U.S. respirator manufacturers who obtain approvals from NIOSH, likely to represent a majority share of the current market supply of NIOSHapproved products covered by this rulemaking, NIOSH benchmark testing indicates that the new TIL requirements can be met by current products without additional development or manufacturing costs. For those manufacturers whose products do not meet the proposed TIL testing standards, NIOSH has estimated design and retooling costs ranging from $55,000 to $200,000 per model or models of respirator with a unique facepiece, depending on the unit volume of production, the type of facepiece seal, and the degree of automation of the manufacturing operation. NIOSH invites comment from manufacturers on these estimates, all of which are based on expert opinion.
It is not possible to estimate the number of current approval holders whose products would not meet the proposed TIL requirements and who would redesign their products to seek new NIOSH approvals, incurring design and retooling costs. However, to the extent that some manufacturers may decide not to redesign products and seek new approvals, the proposed implementation schedule for the new requirements (see Section IV.J of this preamble) would provide other manufacturers sufficient time to increase production capacity and replace products exiting the NIOSHapproved respirator market. NIOSH invites comment from approval holders on their intent to seek new approvals under the proposed requirements.
All manufacturers intending to continue to hold NIOSH approvals for
respirators covered by this rulemaking would incur additional costs for
TIL testing. NIOSH estimates these costs would range from $8,500 to
$12,000 per respirator approval, which would cover a respirator
produced in multiple sizes and may also cover multiple respirator
models employing the same respirator facepiece. The testing costs would
vary based on the number of test subjects required. NIOSH anticipates
applications for up to 500 approvals during the first two years of
implementation of TIL requirements, when NIOSH expects the majority of
requests for approval would be received. NIOSH estimates total testing
and certification costs to manufacturers of up to $3.1 million annually
for these two initial implementation years.\14\ NIOSH anticipates TIL
testing associated with routine submissions for new product approvals
in subsequent years will be required for less than 15 percent of the
NIOSHapproved product market annually, for estimated costs of $825,000 annually.\15\
\14\ This estimate assumes testing and certification of 250
units annually for two years at an average annual cost of $11,000 per unit for a panel of test subjects and $1,250 in other
certification costs. About 30 percent of these other certification
costs will be borne by the manufacturers irrespective of this
proposed rulemaking as a result these products having a typical product life cycle of 5 to 10 years (see note 10 below).
\15\ The product life cycle of these respirators is typically 5
to 10 years; meaning between 10 and 20 percent of 500 NIOSH
certified respirators could be expected to be redesigned annually on
average. However, product redesigns would not necessarily involve
redesign of the facepiece in such a way that would require TIL retesting.
NIOSH does not anticipate additional costs to consumers (e.g., employers, selfemployed workers) as a result of the proposed TIL requirements. The current NIOSHapproved products that NIOSH expects to pass the proposed requirements do not differ substantially in price from comparable products that are not expected to pass without modification.
NIOSH anticipates the TIL requirements will also result in
substantial benefits, although NIOSH lacks information to estimate them
quantitatively. Of greatest importance, substantial numbers of workers
are more likely to derive the expected respiratory protection from
hazardous particulate exposures as a result of using respirators with
adequate TIL performance. As discussed in Section II.C. of this
preamble, NIOSH benchmark testing and other research indicate that many
respirators covered by this rulemaking do not perform well in
preventing substantial inward leakage when tested against diverse
facial types and sizes. Over 50 percent of workers and other respirator
users do not have the benefit of individual fit testing, let alone a
complete respiratory protection program. This suggests that substantial
numbers of workers may receive improved protection as a result of
instituting TIL testing for the certification of these respirators,
increasing the likelihood that a worker without fittesting or training
might obtain adequate TIL performance. Such improved protection will
result in reduced workrelated disease and disability among the
workforce, including such conditions as workrelated silicosis, chronic
obstructive pulmonary disease (COPD), asthma, and cancer, and
biological and infectious diseases such as avian influenza, SARS,\16\
and tuberculosis.17 18 Workrelated COPD and asthma alone
are estimated to cost $6.6 billion annually.\19\ The costs of this
rulemaking would be covered by the prevention of a small fraction of a
percent of the occupational disease burden associated with workplace respiratory hazards.
\16\ Eninger R, Honda T, Adhikari A, HeinonenTanski H, Reponen
T, and Grinshpun S. Filter Performance of N99 and N95 Facepiece
Respirators Against Viruses and Ultrafine Particles. Ann. Occup. Hyg. 2008;52(5):385396.
\17\ Willeke K, Qian Y, Donnelly J, Grinshpun S, Ulevicius V.
Penetration of Airborne Microorganisms Through a Surgical Mask and a
Dust/Mist Respirator. American Industrial Hygiene Association Journal. 1996;57(4):348355.
\18\ Qian Y, Willeke K, Grinshpun S, Donnelly J and Coffey C.
Performance of N95 Respirators: Filtration Efficiency for Airborne
Microbial and Inert Particles. American Industrial Hygiene Association Journal. 1998;59(2):128132.
\19\ Leigh JP, Romano P, Schenker MB, and Kreiss K. Costs of Occupational COPD and Asthma. Chest. 2002;121:264272.
In addition, as discussed in Section II.C. of this preamble, respirators that do not perform adequately in TIL testing would be expected to fail fit testing for employees among employers who conduct fit testing as required by OSHA. This is presumably causing the employers to purchase additional respirator models until all employees have respirators that fit adequately, incurring costs for the non fitting respirators, for repeated respirator fit testing, and for lost employee work time consumed by the repetitive fit testing. NIOSH invites comments from employers regarding the current extent of such costs.
In summary, while NIOSH cannot estimate the total costs associated
with this rulemaking, available information indicates these costs are
modest and also suggests that they are likely to be considerably
outweighed by economic benefits reaped by improved worker protection
and the promotion of increased efficiency among employer respiratory protection programs.
[[Page 56148]]
Through this rulemaking, NIOSH is inviting public comment from
respirator manufacturers, employers, and others to provide greater
specificity for NIOSH estimates of economic costs and benefits
anticipated in association with the implementation of the proposed TIL requirements.
The proposed rule would not interfere with state, local, and tribal governments in the exercise of their governmental functions. B. Regulatory Flexibility Act
The Regulatory Flexibility Act (RFA), 5 U.S.C. 601 et seq., requires each agency to consider the potential impact of its regulations on small entities, including small businesses, small governmental units, and small notforprofit organizations. The Department of Health and Human Services (``HHS'') certifies that this proposed rule would not have a significant economic impact on a substantial number of small entities within the meaning of the RFA.
The majority of respirator manufacturers producing halfmask air purifying particulate respirators approved by NIOSH and covered by this rule are small businesses as defined under the Small Business Act (Pub. L. 85536) for this industry sector (NAICS 339112Medical Instruments and Equipment Manufacturers), employing fewer than 500 employees. For these manufacturers, the proposed rule would establish new TIL requirements applicable to respirators approved by NIOSH for use in potentially hazardous work atmospheres involving toxic, obstructive, and carcinogenic dusts, nanoparticles, and biological and potentially infectious aerosols. Workers don these respirators for protection in a wide variety of industrial sectors, such as mining, manufacturing, construction, and agriculture, and service sectors, such as health care, where medical, nursing, and custodial staff are exposed to biological and potentially infectious aerosols. These respirators are also being stockpiled and would be employed extensively by health care, public health, safety, and other first responders who would be engaged in the case of a pandemic influenza outbreak.
This rulemaking will result in additional costs for TIL testing and certification by NIOSH, for all respirator manufacturers intending to continue to hold NIOSH approvals for respirators covered by this rulemaking. As explained in Section IV.A of this preamble, NIOSH estimates the testing costs would range from $8,500 to $12,000 per respirator approval, which would include a respirator produced in multiple sizes and may also cover multiple respirator models employing the same respirator facepiece. The cost would vary depending on the number of test subjects required. NIOSH anticipates applications for up to 500 approvals during the first 2 years of implementation of TIL requirements, when the majority of requests for approval would be received. NIOSH estimates total testing and certificationrelated costs to manufacturers of $3.1 million annually for these 2 implementation years. NIOSH anticipates TIL testing associated with routine submissions for new product approvals in subsequent years will be required for less than 15 percent of the NIOSHapproved product market annually, for estimated costs of $825,000 annually.
These total testing and certification costs, from the initial 2 year implementation period, when annualized over an average 7.5year product lifecycle, amount to less than $1.01 million annually. This is a small fraction of one percent of the annual revenues of respirator manufacturers, which totaled $1.7 billion in 2001 for all products and have grown extensively since.\20\ Although respirator manufacturers produce a wide range of products beyond those covered by this rulemaking, halfmask airpurifying particulate respirators, including chemical gas mask/filtering respirators, represent the highest volume respirator sales and comprise a large component of total revenues. \20\ Frost and Sullivan Research Service; http://www.frost.com/ prod/servlet/reportbrochure published 30 March 2005.
After implementation, the routine annualized costs to manufacturers
resulting from TIL testing associated with the redesign of products would be less than $141,000.\21\
\21\ This assumes new products would be introduced for 15
percent of the product market annually, resulting in $865,000 of
annual TIL testing costs. These are annualized over a 7.5 year period (the average lifecycle of these products.
As discussed in Section IV.A of this preamble, this rulemaking is not anticipated to result in any additional costs to small employers or selfemployed workers and may result in lower costs. Based on NIOSH benchmark testing, respirators likely to represent a majority share of the current market supply are expected to pass the proposed TIL standards without modification, and these respirators are priced comparably to respirators that are not expected to pass as currently designed. Furthermore, the costs incurred by employers and by self employed workers in selecting adequately fitting respirators through trialanderror processes should be reduced as the implementation of this proposed rule curtails the supply of NIOSHapproved respirators with poor TIL performance.
NIOSH invites the public to provide more specific and current revenue data on the respirator market covered by this rulemaking.
For the reasons provided, a regulatory flexibility analysis, as provided for under RFA, is not required.
C. What Are the Paperwork and Other Information Collection Requirements
(Subject to the Paperwork Reduction Act) Imposed Under This Rule?
The Paperwork Reduction Act is applicable to the data collection aspects of this rule. Under the Paperwork Reduction Act of 1995, a federal agency shall not conduct or sponsor a collection of information from ten or more persons other than Federal employees unless the agency has submitted a Standard Form 83, Clearance Request, and Notice of Action, to the Director of OMB, and the Director has approved the proposed collection of information. A person is not required to respond to a collection of information unless it displays a currently valid OMB control number.
NIOSH has obtained approval from OMB to collect information from respirator manufacturers under OMB Control No 0920109 (Respiratory Protective Devices), which covers all information collection under 42 CFR part 84. This rulemaking would require NIOSH to collect new TIL testing information from manufacturers applying for approval of half mask airpurifying particulate respirators covered by this rulemaking.
NIOSH estimates that the proposed TIL requirements will result in a
minor increase in reporting burden to manufacturers. TIL testing would
require the submission in the application package of one additional
page of data describing the test results. These test results would
already have been recorded by the applicant within the testing process
so the only additional burden to the applicant would be any
reformatting that might be necessary and the transfer of the results
electronically to NIOSH. NIOSH anticipates this reporting, as part of
the standard application package transmitted to NIOSH, would take no
longer than 1 hour for completion; the current information collection
approval pursuant to OMB Control No 0920109 (Respiratory Protective
Devices) estimates 86 hours per submission for each complete application under 42
[[Page 56149]]
CFR 84.11. Accordingly, in conjunction with this rulemaking, NIOSH will
submit a request to OMB to amend its approval under OMB control No 0920109 to collect this additional information.
D. Small Business Regulatory Enforcement Fairness Act
As required by Congress under the Small Business Regulatory Enforcement Fairness Act of 1996 (5 U.S.C. 801 et seq.), HHS would report to Congress the promulgation of a final rule, once it is developed, prior to its taking effect. The report would state that HHS has concluded that the rule is not a ``major rule'' because it is not likely to result in an annual effect on the economy of $100 million or more.
E. Unfunded Mandates Reform Act of 1995
Title II of the Unfunded Mandates Reform Act of 1995 (2 U.S.C. 1531 et seq.) directs agencies to assess the effects of federal regulatory actions on State, local, and tribal governments, and the private sector ``other than to the extent that such regulations incorporate requirements specifically set forth in law.'' For purposes of the Unfunded Mandates Reform Act, this proposed rule does not include any federal mandate that may result in increased annual expenditures in excess of $100 million by state, local or tribal governments in the aggregate, or by the private sector.
F. Executive Order 12988 (Civil Justice)
This proposed rule has been drafted and reviewed in accordance with Executive Order 12988, Civil Justice Reform and will not unduly burden the federal court system. NIOSH has provided TIL requirements it would apply uniformly to all applications from manufacturers of halfmask airpurifying particulate respirators. This proposed rule has been reviewed carefully to eliminate drafting errors and ambiguities. G. Executive Order 13132 (Federalism)
HHS has reviewed this proposed rule in accordance with Executive Order 13132 regarding federalism, and has determined that it does not have ``federalism implications.'' The proposed rule does not ``have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.'' H. Executive Order 13045 (Protection of Children From Environmental Health Risks and Safety Risks)
In accordance with Executive Order 13045, HHS has evaluated the
environmental health and safety effects of this proposed rule on
children. HHS has determined that the proposed rule would have no effect on children.
I. Executive Order 13211 (Actions Concerning Regulations That Significantly Affect Energy Supply, Distribution, or Use)
In accordance with Executive Order 13211, HHS has evaluated the effects of this proposed rule on energy supply, distribution, or use because it applies to the underground coal mining sector since coal mine operators are consumers of respirators. The proposed rule is unlikely to affect the cost of respirators used in coal mines and hence is not likely to have ``a significant adverse effect on the supply, distribution, or use of energy.'' Accordingly, this proposed rule does not constitute a ``significant energy action'' Under E.O. 13211 and requires no further Agency action or analysis.
J. Effective Date
NIOSH proposes that the final rule would take effect 30 days from publication in the Federal Register for all new respirator approval applications for halfmask airpurifying particulate respirators. Approval holders could continue to sell and ship respirators certified under current provisions subpart K as NIOSH/MSHA certified respirators throughout a transition period of three years from the effective date of the final rule and NIOSH would continue to consider modifications to such approvals for two years from the effective date. Continued use of distributed respirators is under the jurisdiction of OSHA and MSHA and would not be affected by this rule. NIOSH anticipates that OSHA and MSHA would permit continued use of those respirators since certifications will not be revoked for respirators sold and shipped by the approval holder during the threeyear transition period. The authority for an approval holder to sell and distribute under a NIOSH certification any halfmask airpurifying particulate respirator certified under the current provisions of subpart K would expire at the end of the threeyear period.
This 3year transition period is proposed to ensure the timely replacement of respirators that demonstrate poor TIL performance while allowing an ample supply of respirators to remain available for use, since even a respirator with poor TIL performance may provide degrees of protection to different users. This timeframe would provide sufficient time for manufacturers to have respirators approved and manufactured in quantities to meet demand. According to NIOSH benchmark testing and other research, significant numbers of currently approved respirators of manufacturers with significant production capacity are likely to pass the proposed TIL testing and performance standards without modifications. On the other hand, NIOSH also seeks to ensure that total quantity of product supply remains sufficient during the transition period for current and potentially higher levels of demand. Such a demand spike could be anticipated if an influenza pandemic were to develop or increase in threat, instigating expanded stockpiling of respirators by health care, public health authorities, employers, workers, and the general public.
NIOSH encourages the public to comment on this proposed implementation schedule and any related issues. Some specific issues for comment include the following:
1. Do manufacturers believe they can meet the proposed TIL performance standards and testing requirements and provide adequate product supply to meet anticipated market demand within the proposed 3 year deadline?
2. Would any parties affected by this proposed rule incur an exceptional and unsupportable financial or other burden as a consequence of the proposed 3year limit on the sale and distribution by approval holders of respirators certified under the current requirements (which omit TIL standards and testing)?
3. Would a different implementation schedule be better justified in terms of balancing the public health, practical, and economic benefits of removing from the market NIOSHapproved respirators with inadequate TIL performance against the public health, practical, and economic benefits of ensuring that an adequate supply of NIOSHapproved respirators remains constantly available? Please describe the advantages and disadvantages of extending or contracting the implementation schedule.
4. Are other factors that have not been identified by NIOSH important to deciding an appropriate implementation schedule? List of Subjects in 42 CFR Part 84
Mine safety and health, Occupational safety and health, Personal protective equipment, Respirators.
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Text of the Proposed Rule
For the reasons discussed in the preamble, NIOSH proposes to amend 42 CFR part 84 as follows:
PART 84APPROVAL OF RESPIRATORY PROTECTIVE DEVICES
1. The authority citation for Part 84 continues to read as follows:
Authority: 29 U.S.C. 651 et seq., and 657(g); 30 U.S.C. 3, 5, 7, 811, 842(h), 844.
Subpart KNonPowered AirPurifying Particulate Respirators
2. Amend Sec. 84.175 by revising the heading and adding new paragraphs (a)(3), and (g) through (i) to read as follows:
Sec. 84.175 Halfmask facepieces, full facepieces, hoods, helmets,
and mouthpieces; fit and total inward leakage (TIL); minimum requirements.
(a) * * *
(3) Halfmask facepieces may be designed and constructed to fit
only one or more defined subpopulations of the general population of
respirator users, such as ``women'' or persons with faces within
specific dimensional limits, provided that the membership of the
subpopulation is readily discernable by the intended users. * * * * *
(g) Any respirator part that must be removed by the respirator user
to perform a user seal check shall be replaceable without special tools and without disturbing the facepiece seal.
(h) User instructions for halfmask respirators shall specify
information necessary to identify the intended population of users:
(1) The applicant shall specify in the user instructions the face
size or sizes that the respirator is intended to fit; pursuant to this
requirement, one respirator may be intended to fit all face sizes; and
(2) If appropriate pursuant to paragraph (a)(3) of this section,
then the applicant shall also specify in the user instructions any
additional descriptions necessary to indicate the subpopulation(s) the
respirator is intended to fit, such as sex, general facial characteristics, and/or precise facial measurements.
(i) Halfmask respirator TIL\1\ testing requirements:
\1\ TIL is the combination of contaminated air leaked through
various potential sources including the facepiecetoface seal, exhalation valves (if any), and gaskets (if any) and any
contaminants that have penetrated the filter.
(1) NIOSH will employ specifications provided in user instructions,
pursuant to paragraphs (h)(1) and (h)(2) of this section, to select
representative test subjects for TIL testing, without further guidance
from the manufacturer. NIOSH will conduct testing on 35 test subjects
for a respirator of a single size or multiple sizes intended to fit the
general population of respirator users, or on 15 or more test subjects
for a respirator of a single size or multiple sizes designed to fit one or more specific subpopulations of respirator users.
(2) Immediately before each test, test subjects will conduct the
user seal check or other donning procedures as specified in the user instructions.
(3) The TIL test shall be administered to each test subject up to
three times, terminating testing either when a test has produced a TIL
value of 1.0 percent or less or after the third test administered to the test subject, whichever occurs first.
(4) A TIL value of 1.0 percent or less shall be achieved by at least:
(i) 26 out of 35 test subjects for a respirator of a single size or
of multiple sizes, designed to fit the general population of respirator users; or
(ii) 12 out of 15 test subjects (or 80 percent of test subjects if
there are more than 15) for a respirator of a single size or multiple
sizes designed to fit one or more specific subpopulations of respirator users.
(5) Each respirator used for testing will be probed approximately halfway between the wearer's nose and mouth.
FOR FURTHER INFORMATION CONTACT
William Newcomb, NIOSH National Personal Protective Technology Laboratory (``NPPTL''), Pittsburgh, PA, (412) 3864034 (this is not a tollfree number). Information requests can also be submitted by email to niocindocket@cdc.gov.