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.

July 19, 1976

MEMORANDUM FOR: Alfred Barden Regional Administrator
Subject: Specific Standards Applicable to Cut-and- Cover Operations in the Construction of Tunnels

This is in reply to your letter of June 10, 1976, regarding cut-and-cover construction of a tunnel. In addition, it confirms a phone conversation Mr. Carvey had with a number of my staff.

When a cut-and-cover operation is must an open cut, the regulations of 29 CFR 1926, Subpart P, Excavation, Trenching, and Shoring, would specifically apply.

When a cover, temporary or permanent, extends over the top of the cut sufficiently to limit access or egress of employees, the movement of air, the amount of natural daylight illumination, or create other problems germane to tunnel operations, the regulations of 29 CFR 1926.800, Tunnels and Shafts, would specifically apply.

When different stages of cut-and-cover operations are concerned, careful evaluation of the employee's exposure would govern which standards are applicable.

Barry J. White
Associate Assistant Secretary
for Regional Programs