CITB Specialists Temporary Works and Scaffolding 2

Question 1

What are the requirements for edge protection on a scaffold working platform used by specialist trades at height?

Accepted Answer

A top guardrail at minimum 950mm, a mid-rail, and a toe board at least 150mm high at every open edge

Answer

The Work at Height Regulations 2005 and NASC guidance require scaffold platforms to have a top guardrail at a minimum height of 950mm above the platform, a mid-rail to prevent anyone falling through the gap, and a toe board at least 150mm high to prevent materials being kicked off the edge. All three elements are mandatory at every unprotected edge.

Question 2

A specialist contractor needs to erect a scaffold over a public footpath. What additional measures are required under UK regulations?

Accepted Answer

A gantry or protected walkway with overhead protection, lighting, and a licence from the local authority

Answer

Scaffolds over public footpaths require a pedestrian gantry providing a minimum headroom (typically 2.4m), overhead protection (fans or boards) to prevent falling objects, adequate lighting, and a scaffold licence from the local authority. The gantry must be designed to carry imposed loads and be regularly inspected.

Question 3

When specialist scaffolding is erected in a location exposed to high winds, what additional design consideration must be applied?

Accepted Answer

A wind loading assessment must be carried out, and the scaffold designed to resist the calculated wind forces, with additional ties and bracing as required

Answer

Wind loading is often the most significant force acting on a scaffold. A wind loading assessment (per TG20 or bespoke design) must calculate the forces based on location, height, topography, and whether the scaffold is sheeted or netted. Additional ties, bracing, and foundation loads are specified to resist these forces. Sheeted scaffolds attract significantly greater wind loads.

Question 4

What is a 'design check category' in relation to specialist temporary works under BS 5975?

Accepted Answer

A classification (1, 2, or 3) that determines the level of independent design checking required based on the complexity and risk of the temporary works

Answer

BS 5975 categorises temporary works into three design check categories based on risk and complexity. Category 1 requires a self-check by the designer, Category 2 requires an independent check by another competent person, and Category 3 (highest risk, such as large falsework or complex temporary structures) requires checking by an independent checking organisation.

Question 5

A specialist scaffolder discovers that a scaffold standard (vertical tube) is resting on soft ground that is beginning to sink. What is the correct action?

Accepted Answer

Stop work, evacuate the scaffold, report to the scaffold supervisor and TWC for an engineered solution such as sole boards or foundations

Answer

Settlement of scaffold foundations is a serious structural issue that can lead to progressive collapse. The scaffold must be evacuated and tagged as unsafe. The TWC and scaffold supervisor must assess the situation and implement an engineered solution — typically sole boards of adequate size to distribute the load, or concrete pads for heavy-duty scaffolds.

CITB HS&E Specialists Practice Test

CITB HS&E Specialists Practice Test

CITB Specialists Temporary Works and Scaffolding 2