CSCS General Safety 4 — Questions and Answers
Question 1: What is the correct hierarchy of control measures when managing risks on a construction site?
- PPE, substitution, elimination, engineering controls
- Elimination, substitution, engineering controls, administrative controls, PPE (Correct answer)
- Administrative controls, PPE, elimination, substitution
- PPE, engineering controls, elimination, substitution, administrative controls
Correct answer: Elimination, substitution, engineering controls, administrative controls, PPE
The hierarchy of controls starts with elimination as the most effective measure and ends with PPE as the least effective.
Question 2: What action should you take before starting work in an area where overhead power lines are present?
- Work quickly to minimize time near the lines
- Check if lines are live and follow a safe system of work including exclusion zones (Correct answer)
- Cover the lines with a tarpaulin
- Only work near them after 6pm when power demand is lower
Correct answer: Check if lines are live and follow a safe system of work including exclusion zones
You must establish whether lines are live and implement exclusion zones, goal posts, or diversion before any work begins.
Question 3: How should an accident book entry be stored to comply with data protection law?
- Pinned to the site notice board for transparency
- Kept securely to ensure personal details are not accessible to unauthorized people (Correct answer)
- Emailed to all supervisors for awareness
- Filed alphabetically by worker surname in an open folder
Correct answer: Kept securely to ensure personal details are not accessible to unauthorized people
Accident book records contain personal data and must be stored securely in compliance with GDPR and data protection legislation.
Question 4: What is the significance of the O2 level dropping below 19.5% in an enclosed space?
- It is acceptable and within normal working range
- It indicates an oxygen-deficient atmosphere requiring immediate evacuation (Correct answer)
- It signals that CO2 scrubbers need replacing
- It means additional ventilation fans should be switched on
Correct answer: It indicates an oxygen-deficient atmosphere requiring immediate evacuation
Oxygen levels below 19.5% are considered oxygen-deficient and create a life-threatening environment in confined spaces.
Question 5: Which of the following best describes an 'imminent danger' situation on a construction site?
- A task that could become hazardous next week if not addressed
- A situation presenting a risk of serious injury or death requiring immediate action (Correct answer)
- Any breach of a site rule regardless of severity
- A near-miss that was avoided without any action needed
Correct answer: A situation presenting a risk of serious injury or death requiring immediate action
Imminent danger refers to conditions where serious harm is likely to occur immediately, requiring work to stop and the area to be cleared.
Question 6: What is the purpose of edge protection on working platforms and excavations?
- To mark the boundary of the work area for planning purposes
- To prevent people, materials, and equipment from falling (Correct answer)
- To support the weight of scaffolding boards
- To act as a visual guide for crane operators
Correct answer: To prevent people, materials, and equipment from falling
Edge protection including guard rails and toe boards prevents falls of people and materials from open edges.
Question 7: If a chemical safety data sheet (SDS) states a substance has an occupational exposure limit (OEL), what does this mean?
- The substance can be used without any protective measures below this level
- Exposure must be controlled to keep concentrations at or below this level to protect health (Correct answer)
- Workers should take a break every time this level is reached
- The substance is banned above this concentration
Correct answer: Exposure must be controlled to keep concentrations at or below this level to protect health
An OEL sets the maximum acceptable airborne concentration of a substance that workers should be exposed to over a specified time period.
CSCS General Safety 4
What is the correct hierarchy of control measures when managing risks on a construction site?