CITB Excavation and Groundworks 2

Question 1

What is 'benching' in the context of excavation safety?

Accepted Answer

Cutting stepped horizontal platforms into the excavation sides

Answer

Benching involves cutting steps or terraces into the sides of an excavation to reduce the height of unsupported face and improve stability, particularly in cohesive soils.

Question 2

What should be done if groundwater begins to seep into an excavation at a significant rate?

Accepted Answer

Immediately stop work and reassess stability

Answer

Groundwater ingress significantly increases the risk of collapse by reducing soil stability; work must stop immediately and a competent person must reassess the excavation before any re-entry.

Question 3

Which regulation primarily governs the safety of excavation operations on UK construction sites?

Accepted Answer

Construction (Design and Management) Regulations 2015

Answer

The Construction (Design and Management) Regulations 2015 (CDM 2015) set out duties for managing health and safety on construction projects, including requirements for safe excavation work.

Question 4

What is the purpose of a 'toe board' at the edge of an excavation?

Accepted Answer

To prevent tools and materials from falling into the excavation

Answer

Toe boards (or kick boards) are fixed at ground level at the edge of excavations to stop loose materials, tools, or equipment from rolling or being kicked into the trench.

Question 5

How should workers access and egress a deep excavation safely?

Accepted Answer

Via a secured ladder or purpose-built access stairway

Answer

Workers must use a secured ladder or purpose-built stairway for safe access and egress, ensuring the access point does not compromise the shoring system.

(CITB) Construction Industry Training Board Practice Test

(CITB) Construction Industry Training Board Practice Test

CITB Excavation and Groundworks 2