Request for Comments and Scientific Information

The National Institute for Occupational Safety and Health (NIOSH) is working to develop appropriate standards and test procedures for Powered Air-Purifying Respirators (PAPR) used to protect workers in hazardous environments. The eventual PAPR standard will identify minimum performance requirements. Future manufacturers may exceed these requirements through innovative design and application of new technology to achieve competitive market differentiation. In developing a standard it is important to be both protective and allow for new technology. As such, new standards should allow for (and in some cases require) advanced technologies, but should not eliminate existing technologies that continue to meet the needs and protection required for many users. The topics identified in this document will be discussed at an upcoming public meeting to be held in Pittsburgh, PA on December 2, 2008, which was announced in the Federal Register on November 5, 2008. http://edocket.access.gpo.gov/2008/pdf/E8-26359.pdf (48 KB; 2 pages)

NIOSH is considering a redefinition of PAPR performance into categories of devices that are breath assisted and those that maintain positive pressure. These categories would be differentiated based upon work rates for which manufacturers may seek approval in the certification process. PAPRs in the breath assisted category would be tested per the manufacturer’s request at work rates of 11 Liters per minute (Lpm), 25 Lpm, or 40 Lpm. PAPRs in the positive pressure category would be tested per the manufacturer’s request at 40 Lpm, 57 Lpm, 78 Lpm, or 99 Lpm.

This approach would expand the list of work rates for which PAPR approval may be sought beyond those described in the December 21, 2007 draft of the proposed PAPR Concept Paper. The work rates identified in the December 21, 2007 draft corresponding to the minute volume breathing rates of 25, 40 and 57Lpm would be retained. Although these work rates should cover the majority of sustainable user activities, NIOSH is seeking stakeholder opinion on addition of a sedentary rate and up to two work rates beyond the currently defined high work rate of 57 Lpm. The 11, 78 and 99 Lpm rates currently being considered are based on the Draft International Standard ISO/TS 16976-1:2005, Classes 1, 7 and 8 for the ISO standard man (body surface of 1.8m2).

NIOSH intends to retain the complete definitions of the 25, 40 and 57 Lpm work rates as presented in Table 1 of the December 21, 2007 draft. This includes the defined tidal volumes and respiration rates as well as a sinusoidal ventilation profile. The proposed sedentary rate of 11 Lpm would have a sinusoidal profile as well. An appropriate ventilation profile has not yet been defined to represent the proposed high work rates of 78 and 99 Lpm.

NIOSH is also considering linking the work rate performance of the breath assisted and positive pressure categories to performance criteria in the laboratory respiratory protection level (LRPL) testing. Devices in the breath assisted category would need to meet an LRPL value of 250. Devices in the positive pressure category would need to meet an LRPL value of 10,000.

Additionally, NIOSH is considering an alternate approach for gas and vapor testing that uses the Wheeler relationship to address assessment of capacity and efficiency at multiple flow rates. Three canisters or cartridges would be tested as received (no preconditioning) at two challenge levels, 25% and 80% relative humidity. Each of the three canisters could be performed at a different flow and conducted until the maximum allowed test penetration. Regression analysis of the resulting service life versus reciprocal test flow rate gives a linear relationship applicable to all flow rates pertinent to the approvals sought.

NIOSH is also considering the establishment of a performance requirement for an End of Service Life Indicator (ESLI) for PAPRs submitted for approval against Organic Vapors and Acid Gases for PAPRs in the positive pressure category. These ESLI would be evaluated using the criteria that are defined in the December 21, 2007 concept paper.

Official comments provided to Docket Number 008-A relating to this document shall be evaluated and be considered in developing the proposed regulation.

Supporting Materials
NIOSH Docket 008 Powered Air-Purifying Respirators	NIOSHdocket0008.html
Proposed Concept, Powered Air-Purifying Respirator Standard, Subpart P, December 21, 2007	0008-122107-proposed_concept.pdf (5.98 MB; 26 pages)
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Input Sought from Stakeholders and Manufacturers

• Opinions on the concept of categorizing PAPRs as breath assisted or positive pressure devices.
• Opinions on the expansion of the number of work rates where PAPRs can be submitted for approval.
• Opinions on the linkage of breath assisted PAPRs and positive pressure PAPRs with LRPL testing.
• Opinions on the consideration of an alternate approach to gas and vapor testing.
• Opinions on the establishment of positive pressure PAPR ESLI for organic vapors and acid gases.

Public Comment Period

Comments will be accepted until 5:00 p.m. ET on January 16, 2009 in accordance with the instructions below. All material submitted to NIOSH should reference Docket Number NIOSH-008-A. All electronic comments should be formatted as Microsoft Word and make reference to docket number NIOSH-008-A.

Comments will be accepted until 5:00 p.m. ET on January 16, 2009

To submit comments regarding this draft publication, please use one of these options:

• Send comments by email.
  
  
• Fax comments to the NIOSH Docket Office: 513-533-8285
  
  
• Send by Mail to:
  NIOSH Docket Office
  NIOSH Mailstop: C-34
  Robert A. Taft Lab.
  4676 Columbia Parkway
  Cincinnati, Ohio 45226

Contact Person for Technical Information

Richard Vojtko at 412-386-5248 or email: dwk5@cdc.gov

NIOSH Draft Documents for Public Review