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.

November 25, 1991

Mr. Chris A. Geckler
Texstar Construction Corp.
1334 N. W. White Road
San Antonio, Texas 78219

Dear Mr. Geckler:

This is in response to your letter of August 23 requesting information on the Occupational Safety and Health Administration's (OSHA) requirements addressing lift-slab bridge construction. We apologize for the delay in responding to your inquiry.

In regard to what OSHA standards apply to bridge construction similar to the example discussed in your letter, please be advised that all the safety and health standards contained in 29 CFR 1926 apply to lift-slab bridge construction, as well as to all other construction sites. In addition, many general industry standards are applicable to construction activities and they are listed in OSHA publication 2207. In regard to specific standards, it appears that three primary concrete construction methods were utilized in the Jamestown-Verrazano bridge project, each having specific concrete construction standards. Section 29 CFR 1926.703 "Requirements for cast-in-place concrete", applies to all cast-in-place portions of the bridge, including the main spans, some pier segments and the closure pours. Section 1926.704 "Requirements for precast concrete", applies to precast sections when lifting inserts are used and when handling and transporting the span sections. Section 1926.705 "Requirement for lift-slab operations", applies while lifting the spans from water level and until the final pour and connections are made. In response to your specific question, please note that a safety factor of 2.5 is required for all jacking components including the jack, cables and lifting attachments during lift-slab operations.

In regard to whether any ANSI standards are included in the OSHA safety standards, please be advised that OSHA regulations incorporate by reference many standards issued by ANSI as well as by other consensus standards organizations. These standards have the same force and effect as other OSHA requirements. In addition, other consensus standards not referenced by OSHA may be used by OSHA for evaluating the safety and health conditions of activities not addressed by existing OSHA standards.

If we can be of further assistance please contact Roy Gurnham or Dale Cavanaugh of my staff in the Office of Construction and Maritime Compliance Assistance at (202) 523-8124.


Patricia K. Clark, Director
Directorate of Compliance Programs