NEBOSH CC Working at Height in Construction 2

Question 1

What is the maximum recommended height for a free-standing mobile tower scaffold used outdoors?

Accepted Answer

The height should not exceed a base-to-height ratio of 1:3 outdoors (or 1:3.5 indoors)

Answer

For stability, mobile tower scaffolds should not exceed a base-to-height ratio of 1:3 outdoors and 1:3.5 indoors. PASMA guidance provides specific recommendations. Outriggers and stabilisers can increase the effective base dimension. The scaffold must never be moved with persons or loose materials on the platform.

Question 2

A construction worker falls 4 metres from a scaffold and is suspended in their safety harness. What is the main risk from prolonged suspension in a harness?

Accepted Answer

Suspension trauma (orthostatic intolerance) which can be fatal within 30 minutes

Answer

Suspension trauma (also called harness hang syndrome) occurs when blood pools in the legs during prolonged vertical suspension, reducing venous return and cardiac output. It can cause unconsciousness within minutes and death within 30 minutes. A rescue plan must be in place before any work at height involving harnesses.

Question 3

Under the Work at Height Regulations 2005, what must be in place before any work at height is carried out?

Accepted Answer

A suitable and sufficient risk assessment with a rescue plan for foreseeable emergencies

Answer

Regulation 4 requires proper planning, including risk assessment, selection of appropriate work equipment, and emergency rescue procedures. No work at height should commence without considering how a fallen or stranded worker would be rescued promptly to prevent suspension trauma.

Question 4

What is the primary advantage of using safety nets as collective fall protection compared to personal fall arrest systems?

Accepted Answer

They protect all workers in the area passively without requiring individual training, fitting, or action

Answer

Safety nets provide passive collective protection — they protect everyone in the work area without requiring individual action, training in use, or correct fitting. This makes them more reliable than personal fall arrest systems which depend on each worker correctly wearing and attaching their equipment.

Question 5

A worker needs to use a ladder to access a scaffold platform 5 metres above ground. What angle should the ladder be set at?

Accepted Answer

75 degrees (1 out for every 4 up)

Answer

Ladders should be placed at an angle of 75 degrees to the horizontal, which equates to a ratio of 1 unit out for every 4 units up (the 1:4 rule or 4-to-1 rule). The ladder must extend at least 1 metre above the landing point, be secured to prevent slipping, and rest on a firm, level surface.

NEBOSH Construction Certificate Practice Test

NEBOSH Construction Certificate Practice Test

NEBOSH CC Working at Height in Construction 2