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Development of Inward Leakage Standards for Half-Mask Air-Purifying Particulate Respirators

August 2013
NIOSH Docket Number 250, CDC-2013-0017

The National Institute for Occupational Safety and Health (NIOSH) of the Centers for Disease Control and Prevention (CDC) is seeking stakeholder participation and comment regarding conceptual development of inward leakage standards for half-mask, air-purifying particulate respirators, currently certified under the provisions of 42 CFR Part 84 Subpart K. This includes both elastomeric facepiece and filtering facepiece type respirators.

NIOSH published a proposed rule on total inward leakage requirements for the same respirators on October 30, 2009 and while the proposed rule was not formally withdrawn, NIOSH does not intend to finalize the 2009 proposed rule. Archived information related to that proposed rule is available at Docket 36 and Docket 137.

Since 2009, NIOSH has continued to build on the science relating to inward leakage requirements for half-mask air-purifying respirators and the practical considerations involved in the implementation of a new concept. NIOSH completed research, a panel variability study, to begin to address some stakeholder comments received following publication of the 2009 proposed rule. Two scientific webinars were held on July 23, 2013 and August 20, 2013, to facilitate dissemination of the panel variability study results and to seek stakeholder feedback concerning the analysis of the data collected during the study.

NIOSH intends to further engage stakeholders by conducting a public meeting on September 17, 2013. The Federal Register Notice announcing the public meeting is available at this link. The Federal Register Notice includes questions where NIOSH is seeking stakeholder input.

NIOSH encourages stakeholders to submit comments regarding the webinar materials or information discussed at the public meeting.

Federal Register Notice:
Notice of draft publication available for public comment; 11/19/13 - Comment Period Extended

Federal Register Notice:
Notice of draft publication available for public comment

Related Materials:

Links to the slides from the presentations included in the webinars and the vocal recordings:

Public Comment Period

Comments will be accepted until 5:00 p.m. EST on December 31, 2013.

Written comments, identified by CDC-2013-0017 and docket number NIOSH-250, may be submitted by any of the following methods:

  • Federal rulemaking portal: Follow the instructions for submitting comments.

    Instructions: All submissions received must include the agency name and docket number (CDC-2013-0017; NIOSH-250). All relevant comments, including any personal information provided, will be posted without change to All electronic comments should be formatted as Microsoft Word.

  • Mail: NIOSH Docket Office
    Robert A. Taft Laboratories
    4676 Columbia Parkway
    Cincinnati, OH 45226