Archive Notice - OSHA Archive

NOTICE: This is an OSHA Archive Document, and may no longer represent OSHA Policy. It is presented here as historical content, for research and review purposes only.

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

December 22, 1988

Mr. Allen R. Schaeffer
Environmental Specialist
Engineering Department
American Trucking Associations
2200 Mill Road
Alexandria, Virginia 22314

Mr. Allen Schaeffer:

This is in response to your letter of November 4, regarding diesel exhaust emissions and the Hazard Communication Standard (HCS) 29 CFR 1910.1200.

Our responses to your questions are numbered in the sequence in which they were posed.

Question 1:

Are diesel exhaust emissions covered under the HCS? If so, please cite specifically the mechanisms which trigger coverage under the HCS.


No, diesel exhaust emissions per se are not covered by the HCS. Diesel fuel however is covered by the HCS and any known hazards associated with this fuel must be reported on the material safety data sheet, including the hazards associated with the combustion of the fuel.

Question 2:

If the answer to (1) is yes, what obligations do motor carriers have with regards to training, labeling, and other provisions of the standard, specifically for diesel exhaust emissions?


All employees are required to develop and implement employee training programs regarding hazards of chemicals and protective measures for all employees exposed to hazardous chemicals in their work areas under normal operating conditions or in foreseeable emergencies. Employees in terminal operations exposed to hazardous chemicals would fall under these provisions. If employees in terminal operations are exposed to diesel fuel in their work areas, the hazards of diesel fuel must be incorporated in the training program. Trucks or other vehicles are not considered work areas for the purposes of the standard. Vehicle operators would not be covered while operating a motor vehicle, however operators would be covered while performing terminal operations.

The chemical manufacturer, importer, or distributor is responsible for labeling containers or diesel fuel. Employers are required to ensure that all containers of hazardous chemicals in the workplace are labeled. Engines, fuel tanks or other operating systems in a vehicle are not considered to be containers for purpose of the HCS and would require labeling.

Question 3:

If the answer to (1) is yes, who or which party is responsible for providing health hazard information on diesel exhaust emissions, such as material safety data sheets?


Manufacturers and importers of diesel fuel are responsible for performing the hazard determination and transmitting the hazard information of diesel fuel to their downstream customers. Employers are not required to evaluate chemicals unless they choose not to rely on the evaluation performed by the chemical manufacturer or importer for the chemical.

Question 4:

If the MSDS are are required, but not available for the chemical manufacturer, what alternatives do motor carriers have for acquiring the MSDS?


Chemical manufacturers and importers are required to provide appropriate MSDS with their initial shipment and with the first shipment after a sheet has been updated. If the MSDS is not provided prior to or with the shipment, it is recommended that the employer write to both the supplier and the product manufacturer to request MSDS as soon as possible. Should the employer fail to receive the requested information, the nearest OSHA Area Office should be contacted for assistance in this matter.

We hope this information is helpful to you. If we can be of further assistance to you, please contact us again.


Thomas J. Shepich, Director
Directorate of Compliance Programs