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.

September 23, 1980

Mr. John P. Murray
Project Safety Manager
Parsons Brinckerhoff/Tudor
P. O. Box 469
Atlanta, Georgia 30301

Dear Mr. Murray:

This is in response to your letter, concerning cut and cover construction in the Atlanta subway project.

We have contacted the Regional and Area offices in Regions III and IV regarding cut and cover tunnel construction and the enforcement of OSHA Instruction STD 3.1. Our review of this matter indicates that the Regions are uniformly enforcing the cut-and-cover instruction which became effective on December 1, 1979. However, it is true as you indicated in your letter that Area Directors do not always apply tunnel safety standards to underground subway stations. Underground subway stations are not always tunnels. The tunnel standards are enforced when a cover, temporary or permanent, extends over the top of the subway station excavation to the extent, that hazards such as those existing in tunnel operations, may be present.

If you still are of the opinion employees are exposed to preventable hazards in underground areas, please provide us with additional details or the employee work exposure, location, etc., and this office will review the situation and provide a determination in accord with our guidelines. I have enclosed for your information a copy of OSHA Instruction STD 3-17.1, formerly OSHA Program Directive 100-55, which permits gas welding and cutting underground under carefully prescribed conditions.

It is noted that the construction standards are minimum safety and health requirements. Employers may enforce more stringent controls for the protection of their employees on their job sites.

I hope this information will we helpful. If we may be of further assistance, please feel free to call or write.


Bruce Hillenbrand
Acting Director,
Federal Compliance and State Programs