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Subchapter 7. General Industry Safety Orders
Group 13. Cranes and Other Hoisting Equipment
Article 99. Testing

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§5022. Proof Load Test and Examination of Cranes and Their Accessory Gear.

(a) Proof load tests of cranes shall be carried out at the following intervals:

(1) In the case of new cranes, before being taken into initial use and every 4 years thereafter.

(2) In the case of uncertificated cranes which have been in use, at the time of initial certification and every 4 years thereafter.

(3) In the case of major modifications or repairs to important structural components, before they are returned to service.

(4) When certificated equipment is out of service for 6 months or more beyond the due date of a certification inspection, an examination equivalent to an initial certification, including proof load test, shall be performed before the equipment re-enters service.

Note: Disassembly and reassembly of equipment does not require recertification of the equipment provided that the equipment is reassembled and used in a manner consistent with its certification.

(b) Proof load tests of cranes shall be carried out with the boom in the least stable direction relative to the mounting.

(c) Proof load tests shall be based on the manufacturer's load ratings for the conditions of use and shall consist of the application of a proof load as close as possible, but not exceeding 110 percent of the load ratings for the boom on the crane. Proof loads shall be applied at the designed maximum and minimum boom angles or radii or as close to these as practicable and at such intermediate radii as the certifying agency may deem necessary. Trolley equipped monorail cranes and overhead cranes shall be tested to a proof load as close as possible, but not exceeding 125 percent of the manufacturer's load rating. Monorail cranes and overhead cranes shall be tested by traversing the proof load weight the full length of the track, bridge/runway(s) and cross-overs, in all directions capable of operation, where practicable. In cases of foreign manufacture, the manufacturer's specifications shall be subject to approval by the certified agent as being equivalent to U.S. practice. The weight of all auxiliary handling devices such as, but not limited to, magnets, hooks, slings, and clamshell buckets shall be considered part of the load, except lifting devices which are designed as an integral part of the crane. Other methods of proof load testing may be substituted for the above where acceptable to the Division.

Note: The manufacturer's load ratings are usually based upon percentage of tipping loads under some conditions and upon limitations of structural competence under others, as well as on other criteria such as type of crane mounting, whether or not outriggers are used, etc. Some cranes utilizing a trolley may have only one load rating assigned and applicable at any outreach. It is important that the manufacturer's ratings be used.

(d) An examination shall be carried out in conjunction with each proof load test. The certificating agency shall make a determination as to requirements for the correction of deficiencies found. The examination shall cover the following points as applicable:

(1) All functional operating mechanisms for improper function, maladjustment, and excessive component wear, with particular attention to sheaves, pins, and drums. This shall include operation with partial load, in which all functions and movements, including, where applicable, maximum possible rotation in both directions, are performed.

(2) All safety devices for malfunction.

(3) Deterioration or leakage in lines, tanks, valves, drains, pumps, and other parts of air or hydraulic systems.

(4) Loose gear components (i.e. hooks, etc.), including wire rope and wire rope terminals and connections, with particular attention to sections of wire rope exposed to abnormal wear and sections not normally exposed for examination. Cracked or deformed hooks shall be discarded.

(5) Rope reeving for compliance with certified agent's recommendations.

(6) Deformed, cracked, or excessively corroded members in crane structure and boom.

(7) Loose bolts, rivets, or other connections.

(8) Worn, cracked, or distorted parts affecting safe operation.

(9) Excessive wear on and free operation of brake and clutch system parts, linings, pawls, and ratchets.

(10) Load, boom angle, or other indicators shall be checked for any inaccuracy.

(11) It shall be ascertained that there is a durable rating chart visible to the operator, covering the complete range of the certified agent's capacity ratings at all operating radii, for all permissible boom lengths and jib length, with alternate ratings for optional equipment affecting such ratings. Necessary precautions or warnings shall be included and operating controls marked or an explanation of controls shall be posted at the operator's position to indicate function.

(12) Careful examination of the junction areas of removable boom sections, particularly for proper seating, cracks, deformities, or other defects in securing bolts and in the vicinity of such bolts.

(13) It shall be ascertained that no counterweights in excess of the certified agent's specifications are fitted.

(14) Such other examinations deemed necessary under the circumstances.


Authority and reference cited: Section 142.3, Labor Code.


1. Amendment of subsections (b), (c) and (d)(5) filed 2-13-75; effective thirtieth day thereafter (Register 75, No. 7).

2. Amendment of subsection (c) filed 4-27-79; effective thirtieth day thereafter (Register 79, No. 17).

3. Amendment of subsection (d) filed 7-6-79; effective thirtieth day thereafter (Register 79, No. 27).

4. Repealer of subsection (d)(12) and renumbering of subsections (d)(13) and (d)(14) filed 1-17-80; effective thirtieth day thereafter (Register 80, No. 3).

5. New subsection (a)(4) filed 12-12-84; effective thirtieth day thereafter (Register 84, No. 50).

6. Amendment filed 8-29-86; effective thirtieth day thereafter (Register 86, No. 39).

7. Editorial correction of printing error in subsection (c) NOTE (Register 94, No. 18).

8. Editorial correction of History 7 (Register 97, No. 23).

9. Amendment of subsection (c) filed 8-25-2003; operative 9-24-2003 (Register 2003, No. 35)

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