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.

October 11, 1995

Bill Bremer, Director
Loss Control, Safety and Health
Tiber Products Manufacturers
951 East Third Avenue
Spokane, Washington 99202

Dear Mr. Bremer:

Your letter dated July 24, requesting clarification of the Hazard Communication Standard (HCS) (29 CFR 1910.1200) with regards to the carcinogenicity of wood dust has been forwarded to my office for response.

Paragraph (g)(2)(vii) of the Hazard Communication Standard requires that the carcinogenicity of hazardous chemicals be identified or reflected on the material safety data sheet (MSDS) for that product. Under paragraph (g)(2)(vii), if a chemicals has been identified on either the National Toxicology Program (NTP) - Annual Report on Carcinogens (latest edition), the International Agency for Research on Cancer (IARC) Monographs (latest editions) or by the Occupational Safety and Health Administration (OSHA), as a carcinogen it must be identified on the MSDS within three (3) months.

The IARC Monograph on Wood Dust (Volume 25, 1995; pages 35-215) has identified hardwood dust as a Group 1 carcinogen. The 1995 Monograph found a clear association between adenocarcinoma of the nasal cavities and paranasal sinuses and occupational exposure to hardwood dust. The report also indicated that there were two few studies to sufficiently evaluate the cancer risk attributable to the workplace exposure to softwood species. In the few studies that have been completed, the risk of cancer from exposure to soft woods appears to be elevated, however there is not enough evidence to make a final determination.

Consequently, the MSDS for hardwood species and those sheets for mixed species of hardwoods and soft woods must be identified as a carcinogen as required under 29 CFR 1910.1200(g)(2)(vii). MSDSs for softwood species (not mixed with hardwoods) do not have to be identified as being carcinogenic.

We hope that this information will be of assistance to you. If you have any further questions please feel free to contact Richard Fairfax of OSHA's Office of Health Compliance Assistance on (202) 219-8036.


John B. Miles, Jr., Director
Directorate of Compliance Programs