CDS Risk Management & Site Safety 3 — Questions and Answers
Question 1: What is the minimum safe approach distance for unqualified workers from energized overhead power lines rated up to 50 kV?
- 3 feet
- 6 feet
- 10 feet (Correct answer)
- 15 feet
Correct answer: 10 feet
OSHA 29 CFR 1926.1408 requires unqualified workers to maintain at least 10 feet of clearance from overhead power lines rated up to 50 kV.
Question 2: During selective demolition of a multi-story building, floors should generally be removed in what order?
- Bottom to top to maintain structural stability
- Top to bottom to prevent overloading lower floors (Correct answer)
- Simultaneously on all floors for efficiency
- Randomly based on equipment availability
Correct answer: Top to bottom to prevent overloading lower floors
Demolition proceeds top to bottom to prevent overloading lower structural members and to maintain control over debris accumulation and structural stability.
Question 3: What is a leading indicator in demolition safety management?
- The number of recordable injuries in the past year
- A trend in near-miss incident reports filed this quarter (Correct answer)
- The total OSHA citations received last inspection
- Workers' compensation costs for the previous project
Correct answer: A trend in near-miss incident reports filed this quarter
Leading indicators like near-miss reports measure proactive safety performance and predict future incidents before injuries occur, unlike lagging indicators.
Question 4: When using a wrecking ball for demolition, the ball weight should generally not exceed what percentage of the crane's rated capacity?
- 25%
- 50% (Correct answer)
- 75%
- 100%
Correct answer: 50%
Industry practice limits the wrecking ball to 50% of the crane's rated capacity to account for dynamic loading forces during swinging operations.
Question 5: A risk matrix in demolition safety is used to:
- Calculate the exact cost of a workplace accident
- Prioritize hazards based on likelihood and severity (Correct answer)
- Assign blame after an incident occurs
- Track worker attendance and productivity
Correct answer: Prioritize hazards based on likelihood and severity
A risk matrix plots hazard likelihood against consequence severity to help prioritize which risks require immediate corrective action.
Question 6: What is the purpose of a competent person designation under OSHA demolition standards?
- To reduce the need for engineering inspections
- To have someone capable of identifying hazards and with authority to take corrective action (Correct answer)
- To serve as the primary safety equipment custodian
- To complete all OSHA recordkeeping forms
Correct answer: To have someone capable of identifying hazards and with authority to take corrective action
OSHA defines a competent person as one with training and experience to identify hazardous conditions and the authority to immediately correct them.
Question 7: Confined space entry during demolition requires which of the following before a worker enters?
- A verbal clearance from the site supervisor
- Atmospheric testing and a written permit (Correct answer)
- Only a safety harness and radio
- Completion of the daily toolbox talk
Correct answer: Atmospheric testing and a written permit
Permit-required confined spaces mandate atmospheric testing for oxygen, flammable gases, and toxic contaminants, plus a written entry permit before workers enter.
CDS Risk Management & Site Safety 3
What is the minimum safe approach distance for unqualified workers from energized overhead power lines rated up to 50 kV?