Hooks and Below-the-Hook Device Inspection

Hooks and Below-the-Hook Device Inspection

Hook inspection

Confirm the hook's required identification and rated load. Inspect the entire hook: attachment or shank, body, bowl or saddle, throat, tip, latch, fasteners, swivel, nut, and retaining devices. Look for cracks, nicks, gouges, wear, corrosion, heat damage, weld spatter, bending, twist, throat spread, and unauthorized repair.

Use gauge marks and original or manufacturer dimensions where provided. A crack is a removal condition. A bent, twisted, opened, or worn hook is not made safe by adding a latch or reducing the planned load.

The OSHA sling rule and B30.10 material must not be blended into one invented threshold:

• OSHA 1910.184 removes a sling hook that is cracked, opened more than 15% beyond normal throat opening at the narrowest point, or twisted more than 10° from the plane of the unbent hook.
• CCO hook reference material illustrates a 5% throat-opening increase, up to a maximum 1/4 inch or manufacturer recommendation, and 10% wear or reduction from original section dimensions for the relevant gauge.
• Current B30.10 and the hook manufacturer may provide the controlling, more restrictive criteria for the exact hook.

On an exam question, identify which source or gauge is stated. In the field, follow every applicable rule and the most restrictive controlling limit. Do not answer “10°” for every kind of deformation or “5%” for every OSHA hook question without reading the source.

Latches and loading

The latch closes the throat to retain slings or accessories when rigging is slack. It is not load bearing. Inspect spring action, alignment, fasteners, and complete closure. A missing or malfunctioning latch must be handled under the hook, job, and applicable OSHA requirements.

Seat rigging in the bowl. Do not point load the tip or force a sling or shackle against the latch. Avoid crowding multiple eyes so they cannot lie freely. If the connection does not fit, use the specified rated collector hardware.

Personnel-hoisting hooks and detachable devices must be capable of closing and locking as OSHA 1926.1431 requires. A self-closing material hook is not necessarily the required positive retention for people.

Below-the-hook device identity

Below-the-hook devices attach between the hoist hook and load. Level I execution specifically includes structural lifting beams, plate clamps, and beam or girder clamps. B30.20 also covers other structural, mechanical, vacuum, and magnetic lifters.

Confirm the nameplate or marking and rated load, device weight where required, model or serial identity, and allowed configuration. Match the device to load material, size, thickness, hardness, surface condition, temperature, and orientation. Do not infer capacity from beam dimensions or clamp jaw size.

The Level I candidate selects and applies a supplied rated device; engineering a BTH-1 design category, service class, or structural factor is not a published Level I outline duty.

Structural lifting beams

Inspect the main member, bails, lugs, pins, shackles, end attachments, welds, and adjustable points. Look for cracks, permanent bending or twist, damaged welds, elongation, wear, corrosion, loose or missing fasteners, and altered hole positions. Confirm movable attachment points lock in the intended positions and the load does not exceed the marked rating for that span or configuration.

A lifting beam generally carries bending; a spreader arrangement generally separates lower pick points and may place its member largely in compression. Actual devices can use more complex load paths. Select by nameplate and engineered configuration, not a slogan about “pure” force.

OSHA 1926.251 requires a custom accessory such as a lifting beam to be marked with safe working load and proof-tested to 125% before use. That proof load is not its operating capacity.

Plate clamps and beam or girder clamps

Inspect plate-clamp body, bail, pins, cam or jaw, teeth, springs, locking lever, and markings. Reject cracks, deformation, worn or contaminated gripping surfaces, damaged locks, missing parts, or failure to move freely. Confirm plate thickness, hardness, surface condition, loading direction, minimum load if specified, and whether one or multiple clamps are allowed by the manufacturer.

A vertical plate clamp is not automatically suitable for horizontal handling, stainless steel, stacked plate, painted surfaces, or side pulling. Never defeat its lock or stand in the fall zone.

For beam or girder clamps, inspect the frame, jaw or screw, spindle, threads, pin, suspension eye, and locking method. Confirm flange size, beam orientation, capacity, and allowed loading direction. Do not side pull a clamp or suspend from a structural member whose capacity has not been approved.

Vacuum and magnetic devices

Where used, inspect pads or magnet faces, seals, hoses, controls, indicators, alarms, power supply, backup systems, and release prevention according to B30.20 and manufacturer instructions. Surface scale, gaps, coatings, thickness, temperature, and material type affect holding force. A magnetic rating on ideal clean plate cannot be transferred blindly to another surface.

Inspection and proof-test outcome

Frequent inspection occurs before or during use as required; periodic inspection is more detailed and documented under the applicable program. A device involved in overload, impact, repair, or suspected damage needs authorized evaluation before return.

Proof testing requirements depend on device type, standard, modification, and jurisdiction. Do not state that every new B30.20 device in every context uses one universal proof-test rule. Apply OSHA's explicit 125% custom-accessory requirement where 1926.251 controls and use B30.20 and manufacturer instructions for the exact device.

The Level I decision remains practical: verify the marking, inspect the load path through the device, confirm permitted application, test function without exposure, and remove or stop for any unresolved defect.