Excavation and Earthwork Safety Flashcards
6 cards from real CSOC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Excavation and Earthwork Safety flashcards as text
What is the main danger of excavation work on Singapore construction sites?
Answer: Collapse of excavation walls (cave-in), which can trap and kill workers
Cave-ins are the most serious hazard in excavation work. The weight of collapsing soil can crush and suffocate workers in seconds. Singapore's WSH regulations require specific protective measures.
At what depth must shoring or other protective measures be used for excavations in Singapore?
Answer: Excavations deeper than 1.5 metres require earth retaining or stabilising structures unless the sides are sloped to a safe angle
Under the WSH (Construction) Regulations, excavations exceeding 1.5 metres in depth must have adequate support systems (shoring, sheet piling) unless the sides are battered back to a safe angle.
What must be done before starting any excavation work on a Singapore construction site?
Answer: Locate underground services (utilities), conduct soil assessment, prepare a safe work plan, and obtain necessary permits
Before excavation, the contractor must locate all underground utilities (water, gas, electricity, telecommunications), assess soil conditions, prepare excavation plans, and obtain permits from relevant authorities.
What access and egress requirements apply to excavations on Singapore construction sites?
Answer: Safe means of entry and exit (ladders, ramps, steps) must be provided within 7.5 metres of any worker in the excavation
Adequate access and egress must be provided so that no worker is more than 7.5 metres from a means of escape. Ladders must extend at least 1 metre above the edge of the excavation.
How should spoil (excavated earth) be stored on Singapore construction sites?
Answer: At least 1 metre away from the edge of the excavation to prevent surcharge loading and material falling back in
Excavated material must be stored at least 1 metre from the excavation edge to prevent additional pressure on the walls (surcharge loading) and to stop material from falling on workers below.
What inspection requirements apply to excavations on Singapore construction sites?
Answer: A competent person must inspect the excavation daily, after rain, and after any event that could affect stability
Excavations must be inspected daily by a competent person, especially after rainfall (which weakens soil), vibrations from nearby work, or any changes in ground conditions that could affect stability.