Bituminous Insurance Companies

OSHA's Publishes New Guidance on Mandatory Respirator Selection

Release Date: April 7, 2009

A new guidance document, Assigned Protection Factors for the Revised Respiratory Protection Standard OSHA 3352-02 2009, published by the Occupational Safety and Health Administration (OSHA), provides employers with vital information for selecting respirators for employees exposed to contaminants in the air. OSHA revised its existing Respiratory Protection Standard 29 CFR 1910.134 in 2006.

This new guide can be used by any employer who needs to implement a respirator protection program. It provides employers with vital information for selecting respirators for employees exposed to contaminants in the air. This guide provides information that answers the following questions:

  1. What are Assigned Protection Factors (APFs)?
  2. What are Maximum Use Concentrations (MUCs)?; and
  3. How to Use APFs and MUCs?

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.

Maximum Use Concentration (MUC) means the maximum atmospheric concentration of a hazardous substance from which an employee can be expected to be protected when wearing a respirator, and is determined by the assigned protection factor of the respirator or class of respirators and the exposure limit of the hazardous substance. The MUC usually can be determined mathematically by multiplying the assigned protection factor specified for a respirator by the permissible exposure limit (PEL), short-term exposure limit, ceiling limit, peak limit, or any other exposure limit used for the hazardous substance. The MUC for respirators is calculated by multiplying the APF for the respirator by the PEL.

The MUC is the upper limit at which the class of respirator is expected to provide protection. Whenever the exposures approach the MUC, then the employer should select the next higher class of respirators for the employees. Employers must not apply MUCs to conditions that are immediately dangerous to life or health (IDLH); instead, they must use respirators listed for IDLH conditions. When the calculated MUC exceeds the IDLH level for a hazardous substance, or the performance limits of the cartridge or canister, then employers must set the maximum MUC at that lower limit.

Within the guide are two attachments: Attachment A is the glossary of the final APF rule; and, Attachment B is the complete final Respiratory Protection standard.

COPYRIGHT ©2009, ISO Services Properties, Inc.

The information contained in this publication was obtained from sources believed to be reliable. ISO Services Properties, Inc., its companies and employees make no guarantee of results and assume no liability in connection with either the information herein contained or the safety suggestions herein made. Moreover, it cannot be assumed that every acceptable safety procedure is contained herein or that abnormal or unusual circumstances may not warrant or require further or additional procedure.


COPYRIGHT ©2009, ISO Services Properties, Inc.
EngineeringAndSafety@ISO.COM