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.

February 26, 1988

Mr. Earle Ganzenmuller
Product Manager
Air-Purifying Products
Scott Aviation
225 Erie Street
Lancaster, New York 14086

Dear Mr. Ganzenmuller:

This is in response to your recent letter concerning respirator canisters for protection against formaldehyde.

You indicated in your letter that the Occupational Safety and Health Administration (OSHA) standard on formaldehyde, 29CFR 1910.1048, does not permit the use of chin style canisters in the respirator selection table, and the test data which accompanied you letter demonstrated that these canisters are at least as effective as the larger size canisters permitted in the OSHA formaldehyde standard.

After reviewing the data you sent to us and after consulting with Health Standards Programs of OSHA, and the Testing and Certification Branch (TCB) of the National Institute for Occupational Safety and Health (NIOSH), we found that the approved Scott "formaldehyde" chin-style canisters would be acceptable for protection against formaldehyde at concentrations up to 100 parts per million (ppm) for up to 2 hours and at concentrations up to 10 ppm for up to 4 hours as well as for emergency escape.

The NIOSH approval label was based on the former formaldehyde standard of 3 ppm. since the Standard has been lowered to 1 ppm, we will contact NIOSH to change the approval label.

Please contact us if you need additional assistance.


Edward Baier
Directorate of Technical Support