Trench shields must be installed to prevent lateral movement in a collapse.
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.
October 20, 1999
Mr. John Randall
Water Utility Safety Coordinator
Water Pollution Control Facilities
7525 Bertram Road SE
Cedar Rapids, Iowa 52403-7111
Re: 1926.652(g)(1)(ii); trench boxes/shield systems for trenches
Dear Mr. Randall: