#1
Which of the following is a safety measure to prevent cave-ins during trenching and excavation?
Inspecting trenches before starting work
ExplanationRegular inspection of trenches before work helps identify potential hazards and ensures a safer working environment.
#2
What is the recommended angle for sloping sides of trenches to prevent collapses?
45 degrees
ExplanationA 45-degree slope is recommended to prevent collapses and maintain stability in trench walls.
#3
Which of the following is NOT a potential hazard associated with trenching and excavation?
Excessive noise
ExplanationExcessive noise is not a direct hazard associated with trenching and excavation work.
#4
Which agency sets safety standards for trenching and excavation?
OSHA (Occupational Safety and Health Administration)
ExplanationOSHA sets and enforces safety standards to ensure a secure working environment for trenching and excavation activities.
#5
What is the recommended maximum depth for trenching without additional protective systems?
4 feet
ExplanationTrenching without protective systems is generally recommended up to a maximum depth of 4 feet for safety.
#6
Which of the following soil types is considered the most stable for trenching and excavation?
Clay
ExplanationClay is considered the most stable soil type for trenching due to its cohesive nature.
#7
What does the term 'benching' refer to in trenching and excavation?
Creating a stair-like configuration in the trench walls
ExplanationBenching involves creating steps or a stair-like configuration in trench walls to enhance stability.
#8
What is the primary purpose of trench boxes or shields in excavation work?
To provide support to the trench walls
ExplanationTrench boxes or shields offer support to trench walls, preventing collapses and ensuring a safer working environment.
#9
What is the minimum distance at which heavy equipment should be kept from the edge of a trench?
5 feet
ExplanationKeeping heavy equipment at least 5 feet away from trench edges helps prevent accidental collapses or damage.
#10
What is the purpose of conducting soil tests before trenching and excavation?
To assess soil stability and identify potential hazards
ExplanationSoil tests help evaluate stability and identify potential hazards, guiding appropriate safety measures.
#11
Which of the following is NOT a proper safety practice when working in a trench or excavation?
Ignoring warning signs of potential cave-ins
ExplanationIgnoring warning signs increases the risk of accidents; proper attention to signs is crucial for safety.
#12
What should workers do if they notice signs of a potential trench collapse while working?
Quickly exit the trench and report the hazard
ExplanationPromptly exiting the trench and reporting the hazard is crucial in preventing accidents related to trench collapses.
#13
What is the maximum allowable depth for a trench when protective systems are used?
15 feet
ExplanationWith proper protective systems in place, the maximum allowable depth for a trench is 15 feet for enhanced safety.