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.

February 18, 1999

Mr. Steven D. Claypool
15516 Budge St.
San Leandro, CA 94579

RE: 1926.451(g), 1926.453, 1926.502(d);

Dear Mr. Claypool:

This is in response to your letter dated July 31, 1998 to the Occupational Safety and Health Administration (OSHA), in which you express concern over the use of personal fall arrest systems to protect employees when working from aerial lifts. Your specific concern is that aerial lifts may tip over from the arresting forces generated when a worker falls while wearing a personal fall arrest system.

A provision in OSHA's aerial lift standard for construction, §1926.453(b)(2)(v), requires fall protection for employees in aerial lifts. An employer can comply with that requirement by using either a restraint system or a personal fall arrest system. A restraint system consists of a body belt or harness, lanyard and anchor. The system is arranged so that the worker is prevented from falling any distance.

A system that exposes a worker to a fall, but stops the fall within specified parameters, is a personal fall arrest system. The criteria for fall arrest systems are in 29 C.F.R. §1926, subpart M. Section 1926.502(d)(15) provides that "anchorages used for attachment of personal fall arrest equipment shall be . . . capable of supporting at least 5,000 pounds per employee attached, or shall be designed, installed and used as follows: (i) as part of a complete personal fall arrest system which maintains a safety factor of at least two . . . ."

When using a personal fall arrest system, that system must not be anchored to an aerial lift unless the aerial lift is capable of withstanding the loads imposed by an arrested fall. Under §1926.502(d)(16)(iii), the maximum distance a worker is allowed to fall is 6 feet. Some aerial lifts may not be designed to withstand the impact of a 6 foot arrested fall. However, if the fall arrest system is set up to limit the fall to less than 6 feet, the impact forces will be lessened (the strength requirements for the anchorage are met as long as it has a safety factor of two). That may bring the arresting forces within the capabilities of some of those aerial lifts. If this cannot be achieved, then a restraint system must be used. Note that if a restraint system is used, there is no need to provide for prompt rescue under §1926.502(d)(20), since there would not be an arrested fall.

You ask if we are aware of any studies where the capability of aerial equipment to withstand the forces of arrested falls were tested; we are not aware of any such tests. You also ask if there is a procedure for petitioning for an amendment to the standard to address this problem. You may send a request to us asking that a particular change in a standard be placed on OSHA's Regulatory Agenda. We are currently preparing an Advance Notice of Proposed Rulemaking on a variety of fall protection issues.

If you require any further assistance, please do not hesitate to contact us again by writing to: USDOL-OSHA, Directorate of Construction, Office of Construction Standards, Room N3621, 200 Constitution Ave., NW, Washington, D.C. 20210.


Russell B. Swanson, Director
Directorate of Construction