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


January 2014
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) sought 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 included 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inward leakage requirements for the same respirators on October 30, 2009 and while the proposed rule was not formally withdrawn, NIOSH does not intend to finalize the 2009 proposed rule.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 intended 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 included questions where NIOSH is seeking stakeholder input.

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

The Notice of Proposed Rulemaking and Background Information are provided below. To view comments submitted on the proposed rule visit, enter CDC-2013-0017 in the search field, then click “Search”.

Background Information

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