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.

August 18, 1986

Paul W. Willard, Ph.D.
Manager, Product Regulatory
3M Center
St. Paul, Minnesota 55144

Dear Dr. Willard:

This is in response to your letter of June 25 concerning the requirements for listing multiple exposure limits on material safety data sheets under the Occupational Safety and Health Administration's (OSHA) Hazard Communication Standard (HCS).

It is the intent of the standard that employees and manufacturing users have a fundamental right to know the existing exposure limits of the substances with which they work. OSHA therefore encourages chemical manufacturers and importers to disclose all known exposure limits on the material safety data sheets.

From a compliance standpoint the material safety data sheet must contain the OSHA permissible exposure limit (PEL), and any more protective exposure limit, if one or more exists. Failure to include a less protective exposure limit, other than the OSHA PEL, will be considered a de minimis violation and will not result in the issuance of a citation.

Please feel free to contact us again if further assistance is needed.


John B. Miles, Jr., Director
Directorate of Field Operations

June 25, 1986

Mr. John Miles
U.S. Department of Labor
Occupational Safety and Health
200 Constitution Avenue, N.W.
Washington, DC 20210

Re: MSDS - Exposure Limits

Dear Mr. Miles:

At 3M we have established a policy of placing the most conservative exposure limit and the source, i.e. ACGIH, OSHA, on the Material Safety Data Sheet. We do not customarily list all TLVs, PELs, etc. We believe this practice is prudent, since it is not confusing to those reading the MSDS and does not cloud the primary objective of clear, effective hazard communication and well-founded precautionary information. In addition, this is good practice for averting liability claims.

I understand from Mr. Gibbs that OSHA Region 5 has already adopted this policy. We would like to see acceptance of this policy in all OSHA regions. We are requesting concurrence from Federal OSHA that we are required to designate only one exposure limit which will be the most conservative.


Paul W. Willard, Ph.D.
Manager, Product Regulatory Toxicology
Diplomat of the American Board of Toxicology