Standard Interpretations
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. Each 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.
- 1926.650 - Manufacturer's Tabulated Data in the design and application of trench safety systems. - 10/01/1991
- 1926.650 - Stacking trench boxes in trenches. - 10/29/1991
- 1926.650 - Testing of type C soil is not necessary if employees are adequately protected. - 06/05/1991
- 1926.650 - Trench shield must extend 18" above excavation walls when below grade. - 08/10/2000