Trench shield must extend 18" above excavation walls when below grade.

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 10, 2000 [Reviewed May 31, 2018]

Mr. Michael W. West
Director of Engineering and Materials Management
Efficiency Production, Inc.
685 Hull Road
Mason, Michigan 48854

Dear Mr. West:

This is in response to your letter of December 7, 1999, in which you request that we provide an interpretation of the Occupational Safety and Health Administration's (OSHA) standards for excavations. We apologize for the delay in providing this response.