Cable jib stops and prohibited belly slings

NOTICE: This is an OSHA Archive Document, and may no longer represent OSHA Policy. It is presented here as historical content, for research and review purposes only.

April 29, 1980

MEMORANDUM FOR: ROBERT WENDELL
REGIONAL ADMINISTRATOR

ATTENTION: G. L. Wyatt, ARA for Technical Support

THRU: ROGER CLARK
Field Coordinator

FROM: GROVER C. WRENN
Director, Federal Compliance and State Programs

SUBJECT: Cable Type Jib Stops

This office concurs with the interpretation dated January 25, 1972, (copy enclosed) written by Gerald F. Scannell to Mr H. H. Damman, Manitowoc Engineering Company, concerning cable type belly slings.

Cable type belly slings are prohibited by reason of their point of attachment and sag. If a sudden thrust were imposed on the jib, such as loss of load or high wind, an additional stress would be added to the load imposed by the overtopping action of the jib.

The cable stop shown in the diagram, Figure 680, would not be considered a belly sling since it is attached to an off-set lug on the jib parallel to the hinge pin of the boom and jib and at right angles to the jib. The configuration of this device makes it a "positive" type jib stop. The cable in the design is below the hinge point and does not come within the meaning of "cable type belly sling," as mentioned in our standard. Cable type belly sling(s) mentioned in 29 CFR 1926.550(b)(1) would be a sling or set of slings suspended from jury rigged, temporary attachment points on the boom and jib with the mid-span of the suspended cable hanging loosely below the boom-jib connection pin location.

Engineered cable stays or pendants attached to suitable lugs, torque arms, or guide struts extending from the boom-jib attachment points which will prevent overtopping of the jib as described in the subject standard are acceptable.

However, problems such as those raised in your memorandum should be checked by the compliance officer, and any alleged violations of Section 5(a)(1) of the act shall be cited accordingly. Cables are used as a positive boom stop satisfactorily, by at least one manufacturer, and are addressed by ANSI B30.5 - 1968.