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.

April 17, 1996

Mr. T. W. Elmy
Aluminum Company of America
2300 N. Wright Road
Alcoa, Tennessee 37701

Dear Mr. Elmy:

This is in response to your letter of March 28, 1996 requesting an interpretation regarding the standards applicable to a barge-mounted stiffleg derrick engaged in the repair and maintenance of a dam site.

In your letter you advised us that this barge-mounted stiffleg derrick performs functions such as lifting structures (e.g., inlet screens, gate rollers) for repair and maintenance upkeep, and lifting accumulated debris. Further, it was specified that this derrick does not perform any longshoring activities such as cargo transfer between shore-vessel, vessel-vessel, etc.

The operations associated with the use of this barge-mounted stiffleg derrick fall under "marine construction" and, as a consequence, the applicable standards for this barge-mounted derrick application are 29 CFR §1926.550 and §1926.605.

You advised us that the company is contemplating replacing the current derrick with a barge-mounted land-based crane. The same regulations would apply to a land-based crane temporarily mounted on a barge and performing the same duties at this dam site.

For your information, we have enclosed a copy of OSHA Instruction STD 3-13.2, "29 CFR 1926.605(a)(1) As Applied to Marine Construction", to provide further clarification with respect to the transfer of materials and equipment.

Should you have any further question or require additional assistance please contact us at (202) 219-8131.


Joe Nolan
Division of Maritime
Compliance Assistance