OSHA requirements are set by statute, standards and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at https://www.osha.gov.

April 24, 2018

Mr. Kevin Cochran
1760 Western Drive
West Chicago, Illinois 60185

Dear Mr. Cochran:

Thank you for your letter to the Occupational Safety and Health Administration (OSHA). Your email letter has been referred to the Directorate of Enforcement Programs for a response. Your letter requested clarification of OSHA's Respiratory Protection standard, 29 CFR 1910.134, which addresses filtering facepiece respirators and medical evaluations, among other requirements. This letter constitutes OSHA's interpretation only of the requirements discussed herein, and may not be applicable to any questions not delineated within your original correspondence. Your paraphrased question and our response are below.

Question 1: Does a respirator meeting OSHA's definition of a filtering facepiece respirator (regardless if it's elastomeric) need to be included in the medical evaluation of the respiratory program when used voluntarily?

Response: First, we would like to clarify that a filtering facepiece respirator (or dust mask) and an elastomeric respirator are both air-purifying respirators, but they are not equivalent respirators. OSHA defines at 29 CFR 1910.134(b) a filtering facepiece respirator (dust mask) as a negative pressure particulate respirator with a filter as an integral part of the facepiece or with the entire facepiece composed of the filtering medium (as mentioned in your incoming letter) (see 63 Fed. Reg. 1152, 1183 (January 8, 1998)). On the other hand, the elastomeric respirator is a tight-fitting, air-purifying respirator with replaceable filters, cartridges, or canisters. The design of elastomeric respirators is such that the filtering medium is not the only fundamental part needed to make the facepiece functional. The elastomeric (e.g., rubber, silicone, neoprene, plastic) material allows the respirator to be cleaned, and reused. Elastomeric respirators can be used for many gases and vapors if equipped with the proper cartridges.

As OSHA explained in the respiratory protection compliance directive, Inspection Procedures for the Respiratory Protection Standard, CPL 02-00-158, the requirements for voluntary use of respirators can be divided into two categories: requirements for filtering facepieces (i.e., dust masks) and for all other respirators, including elastomeric facepieces and powered air-purifying respirators. If an employer only allows voluntary use of filtering facepiece respirators after determining that such use will not itself create a hazard, the employer's only further obligation under the Respiratory Protection standard is to provide a copy of Appendix D of the standard to each voluntary user of a filtering facepiece. See 29 CFR 1910.134(c)(2). If employers allow the voluntary use of elastomeric facepiece and powered air-purifying respirators (again, after determining that such use will not itself create a hazard), the employer must implement the elements of a written respiratory protection program necessary to ensure that employees voluntarily using such respirators are medically fit to do so, and that the respirator is cleaned, stored, and maintained so that its use does not present a health hazard to the user. See 29 CFR 1910.134(c)(2)(ii). The preamble to the standard explains that medical evaluation is necessary even for voluntary use of negative pressure (tight-fitting) respirators because they impose a significant physiologic burden on the respirator user, and it is crucial to determine that the user can withstand that burden without suffering adverse health consequences (63 Fed. Reg. at 1190).

Thank you for your interest in occupational safety and health. We hope you find this information helpful. OSHA's requirements are set by statute, standards, and regulations. Our letters of interpretation do not create new or additional requirements but rather explain these requirements and how they apply to particular circumstances. This letter constitutes OSHA's interpretation of the requirements discussed. From time to time, letters are affected when the agency updates a standard, a legal decision impacts a standard, or changes in technology affect the interpretation. To assure that you are using the correct information and guidance, please consult OSHA's website at http://www.osha.gov. If you have further questions, please feel free to contact the Office of Health Enforcement at (202) 693-2190.



Thomas Galassi, Director
Directorate of Enforcement Programs