CHST Crane and Rigging Safety 3

Question 1

What does the term 'Working Load Limit' (WLL) mean for rigging hardware?

Accepted Answer

The manufacturer-rated maximum load that rigging hardware is designed to handle in regular service

Answer

The ultimate breaking strength of the rigging component

Answer

The load at which rigging hardware will permanently deform

Answer

The load at which proof testing is conducted

Question 2

Under OSHA 1926.251(c)(3), what is the required design factor for wire rope slings used in rigging operations?

Accepted Answer

5:1 (the minimum breaking force must be at least 5 times the rated capacity)

Answer

3:1

Answer

4:1

Answer

2:1

Question 3

As the angle between two sling legs increases (the legs spread farther apart), what happens to the tension in each sling leg for the same load?

Accepted Answer

Tension in each leg increases as the angle between the legs increases

Answer

Tension in each leg decreases as the angle increases

Answer

Tension stays constant regardless of angle

Answer

Tension only changes when the angle exceeds 90 degrees

Question 4

Under OSHA 1926.251, which condition requires a wire rope sling to be removed from service immediately?

Accepted Answer

Ten randomly distributed broken wires in one rope lay or five broken wires in one strand in one rope lay

Answer

Any visible surface rust

Answer

Abrasion reducing wire diameter by less than 1/64 inch

Answer

A single kinked section less than 1 inch in diameter

Question 5

What is a 'critical lift plan,' and for which types of lifts is it required?

Accepted Answer

A documented analysis and plan required for lifts exceeding 75% of rated capacity, tandem lifts, or lifts over energized power lines or occupied areas

Answer

A mandatory OSHA form required for all crane lifts regardless of load

Answer

A permit only required when the load exceeds the crane's rated capacity

Answer

A plan prepared only for tower crane assembly and disassembly

Question 6

Under OSHA 1926.1402, what must be done when a crane is set up on a surface where ground bearing capacity is uncertain?

Accepted Answer

A qualified person must determine the bearing capacity and, if inadequate, use mats, cribbing, or other support to distribute the crane's load safely

Answer

The lift must be cancelled until a structural engineer inspects the site in person

Answer

Only the crane manufacturer may approve an alternative setup

Answer

The operator may proceed with reduced load if the soil appears firm