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 27, 1992

Mr. Bob Richards
Project Engineer
Duff-Norton Company, Inc.
P.O. Box 7010
Charlotte, NC 28241-7010

Dear Mr. Richards:

This is in response to your September 24 letter requesting the Occupational Safety and Health Administration (OSHA) to clarify the requirements of 29 CFR 1926, Subpart P -- Excavations.

Your specific question concerns whether or not OSHA requires manufacturer's tabulated data (MTD) to identify a registered professional engineer. The OSHA regulations at 1926.652(c) Design of Support Systems, Shield Systems, and Other Protective Systems, set forth four options for the design of protective trench systems. Option (3) - Designs using other tabulated data, and Option (4) - Design by a registered profession engineer, respectively require the registered professional engineer who develops the tabulated data or approves the design of the protective system to be identified in writing and such information must be maintained at the jobsite. However, the other options, including Option (2) - Designs Using Manufacturer's Tabulated Data, do not specifically require the registered engineer to be identified in writing. The confusion among your customers may stem from these differences.

Please note, however, that although Option (2) does not specifically require the engineer who prepared the MTD to be identified, MTD by definition means tables and charts approved by a registered professional engineer. Without proof of this approval, such as an engineers stamp, it will be difficult for a contractor using an MTD based system to establish compliance with the requirements of Subpart P. Therefore, it may be to your benefit to provide this information although it is not required.

If you have further questions, please do not hesitate to contact me or Mr. Dale Cavanaugh of my staff at (202) 219-8136.


Roy F. Gurnham, Esq., P.E.
Office of Construction and Maritime
Compliance Assistance