Standard Interpretations - Table of Contents
• Standard Number: 1910.178; 1910.178(k)(3)


This letter constitutes OSHA's interpretation only of the requirements discussed and may not be applicable to any situation not delineated within the original correspondence.


April 14, 2008

Mr. Milton Pleasant
Alcoa Inc.
Reynolds Wrap Center
3041 Wilson Ave.
Louisville, KY 40211

Dear Mr. Pleasant:

Thank you for your letter of September 13, 2007, to the Occupational Safety and Health Administration's (OSHA's) regional office in Atlanta, Georgia. Your letter has been forwarded to OSHA's Directorate of Enforcement Programs (DEP). You had a question concerning OSHA's Powered industrial trucks standard, 29 CFR 1910.178, and the use of jack stands in the stabilization of semi-trailers. Your paraphrased question and our response follow.

Question: Are two jack stands, placed one on each side of the uncoupled end of a semi-trailer, sufficient to support the trailer and prevent it from upending during loading and unloading using powered industrial trucks? Is one jack stand placed in the middle of the uncoupled trailer sufficient?

Response: OSHA's Powered industrial trucks standard, at 29 CFR 1910.178(k)(3), states that "[f]ixed jacks may be necessary to support a semi-trailer and prevent upending during loading or unloading when the trailer is not coupled to a tractor." OSHA's standard does not specify a particular type of jack, nor the number and placement of such jacks. As noted in the March 19, 1991, letter to Mr. Thomas Wheeler (enclosed), the language in this paragraph is advisory rather than mandatory. However, when using portable jacks to support semi-trailers, OSHA strongly