When trench soil classification tests are required

March 10, 1992

Mr. Mark Monson
Manager of Projects
Chicagoland Construction
Safety Council
[Recipient address omitted]
Dear Mr. Monson:

This is in response to your letter, postmarked January 16, requesting an interpretation of Occupational Safety and Health Administration regulations addressing the classification of soils for purposes of providing protective systems in excavations.

In regard to when soil classification tests are required, please be advised that if excavations are 20 feet or less in depth and sloped in accordance with the requirements of 1926.652(b)(1)(i) (i.e. the slope is not greater than 34 degrees measured from the horizontal), then soil classification tests are not required. Consequently, if an employer assumes type C soil is present, and provides protection (sloping, shoring or shielding) as required for type C soil, the intent of the requirement for soil classification tests would be met and a citation should not be issued. However, soil classification tests are required if the employer elects to use any other option.

If we can be of any further assistance, please contact Mr. Roy F. Gurnham or Mr. Dale R. Cavanaugh of my staff in the Office of Construction and Maritime Compliance Assistance at (202) 523-8136.

Sincerely,
Patricia K. Clark, Director
Directorate of Compliance Programs