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 http://www.osha.gov.

May 21, 1992 [Reviewed November 8, 2018]

Mr. Curtis P. Parrish
Vice President of Finance
Wm. G. Knowles Construction Company
P.O. Box 385 - Route 3
North Chester, Illinois 62233

Dear Mr. Parrish:

This is in response to your April 16 letter requesting an interpretation of an Occupational Safety and Health Administration standard addressing the design of protective systems used in trenches.

You are correct that 29 CFR 1926.652(c), Option (2) allows support systems, shield systems and other protective systems to be designed using manufacturer's tabulated data without additional certification from a registered professional engineer (RPE). Tabulated Data by definition (ยง1926.650(b)) is required to be certified by a RPE and additional certification is not necessary.

Thank you for your interest in occupational safety and health. We hope you find this information helpful. OSHA requirements are set by statute, standards, and regulations. Our letters of interpretation do not create new or additional requirements but rather explain these requirements and how they apply to particular circumstances. This letter constitutes OSHA's interpretation of the requirements discussed. From time to time, letters are affected when the Agency updates a standard, a legal decision impacts a standard, or changes in technology affect the interpretation. To assure that you are using the correct information and guidance, please consult OSHA's website at https://www.osha.gov. If you have further questions, please feel free to contact the Directorate of Construction at (202) 693-2020.*

Sincerely,



Patricia K. Clark, Director
Directorate of Compliance Programs

*[This letter has been modified (non-substantive changes) on November 8, 2018, and reflects current OSHA regulations and policies.]