NWSA Rigging and Hoisting Operations 2

Question 1

What is the purpose of a tag line during a tower hoisting operation?

Accepted Answer

To control the load's rotation and lateral movement during lifting and lowering

Answer

Tag lines allow ground personnel to guide and stabilize loads during hoisting, preventing spinning, swinging, and contact with the tower structure.

Question 2

What must be done before using a synthetic sling for hoisting on a tower?

Accepted Answer

Inspect for cuts, abrasion, UV degradation, knots, acid damage, and verify the sling is rated for the intended load

Answer

Synthetic slings degrade from UV exposure, chemicals, heat, and physical damage. Pre-use inspection prevents sling failure.

Question 3

What is the significance of the D/d ratio in rigging operations?

Accepted Answer

It is the ratio of the diameter of the object the wire rope bends around to the diameter of the rope itself, affecting rope strength and lifespan

Answer

When wire rope bends around small-diameter objects, internal stresses increase dramatically, reducing strength and accelerating fatigue failure.

Question 4

What determines the safe working load limit for a shackle used in tower rigging?

Accepted Answer

The working load limit stamped on the shackle body by the manufacturer, which must never be exceeded

Answer

Every rated shackle has a working load limit permanently marked on its body. Exceeding this limit risks catastrophic failure.

Question 5

Why is a load calculation required before every hoisting operation on a tower?

Accepted Answer

To verify that all rigging components and anchor points can safely support the load with appropriate safety factors

Answer

Without accurate load calculations, rigging components could be overloaded, causing equipment failure and potentially fatal injuries.

NWSA - National Wireless Safety Alliance Practice Test