19.3 Below-the-Hook Device Inspection and Testing

Inspect the complete lifting device

ASME B30.20 covers below-the-hook lifting devices. Inspection must suit the type of device: a lifting beam needs structural examination, while a vacuum lifter also needs sealing-system and indication checks. A magnet, clamp or grapple requires attention to its own load-retaining and release mechanisms. Do not treat every device as a steel bar with an annual weld test.

The CCO reference manual reproduces B30.20-2018 material for structural and mechanical devices. It describes every-lift and frequent observations and assigns assessment of hazardous damage to a qualified person. The inspection program also includes periodic examination under the applicable complete standard and manufacturer instructions. The source's edition and device chapter matter when selecting intervals and records.

Every-lift observations identify debris on the load surface, condition and operation of controls, and condition and operation of indicators or meters where installed. Frequent inspection considers structural deformation, cracks or excessive wear; loose or missing guards, fasteners, covers, stops and nameplates; hold-and-release mechanisms; and missing or illegible operating-control markings.

Identification supports safe selection

For the new structural/mechanical devices described in CCO's excerpt, required identification includes manufacturer name and contact information, unique serial number, rated load, ASME BTH-1 design category and service class, plus applicable electrical information. The excerpt requires lifter weight marking if over 100 lb. Do not convert that condition into an identical marking requirement for every device chapter or every lighter accessory.

The rated load must be legible on the structure or an attached tag where visible. Detachable lifters forming part of a group also need their individual rated loads as specified. Missing information must be resolved through traceable manufacturer/design records; capacity cannot be guessed from beam size, paint color or the capacity of the crane carrying it.

A design category and service class describe design and duty considerations, not extra payload capacity. A high-duty device still must remain within its rated load, geometry and operating limits. Repeated cycling can make fatigue and inspection history particularly important even if individual loads are below capacity.

Device-specific examination

A device may pass a structural visual check while failing a functional one. For example, an intact plate clamp with a failed locking mechanism cannot be used merely because its body has no crack. Likewise, a vacuum frame with a readable plate is not ready if its required alarm or retention test fails.

Use safe unloaded testing procedures and protected access. Never inspect a closing jaw with fingers inside it or diagnose a leaking hydraulic system beneath a suspended load. Where disassembly or specialized examination is required, the authorized person must perform it under an isolated, supported condition.

Frequent and periodic inspection

Choose intervals according to service severity, frequency, environment, manufacturer directions and the applicable standard. Abrasion, corrosion, heat, repeated load cycles and unusual events can require additional examination. A shock load or collision must be reported and assessed even when the next periodic inspection is months away.

Periodic examinations may require measurements and access beyond a routine visual pass. Record identity, date, findings, corrective actions and the responsible person as required by the inspection program. Keep prior dimensions and repair history available. Do not assume nondestructive testing of every weld is universally mandatory at an annual interval; the applicable procedure and qualified assessment determine its use.

Proof testing is application-specific

A proof test applies a specified load to verify an assembly under controlled conditions. It is not a rigger's informal attempt to lift more than WLL and is not a substitute for inspection. Testing may require a defined load, hold, configuration, examination and documented result. A passed test does not approve an unauthorized alteration made afterward.

OSHA 1926.251(a)(4) specifically requires custom-designed grabs, hooks, clamps and other lifting accessories for units such as modular panels and prefabricated structures to be marked and proof tested before use to 125% of rated load. That provision does not mean all commercially manufactured below-the-hook devices receive the same test at every jobsite. Personnel-platform testing under 1926.1431 is another distinct requirement.

Specific test example

A custom accessory within 1926.251(a)(4) is rated 4,000 lb. Its specified proof load is 1.25 × 4,000 = 5,000 lb. Successful completion does not raise its WLL to 5,000 lb. The accessory remains rated 4,000 lb and must be used in its approved arrangement, with compatible connections and an adequate crane load inventory.

Removal and return to service

Stop use for damage, malfunction or missing required identification. Isolate and report the device. Do not weld an extension to a spreader, add a new lifting hole, bypass a release interlock or retag a device using an unverified field estimate. These actions can change strength, stability or retention.

Repairs or modifications need the authorized design/manufacturer or qualified-person process, inspection and applicable testing before return. Confirm corrected markings and instructions match the final assembly. Preserve records with the equipment so future users can distinguish an approved repair from an unexplained alteration.

Sources: CCO reference manual, B30.20-2018 excerpts, OSHA custom-accessory requirement, manufacturer equipment guidance.