CHST CHST - Construction Health and Safety Technician Emergency and Fire Preparedness Questions and Answers 5 — Questions and Answers
Question 1: What is the recommended minimum clear width of an egress path on an active construction site to accommodate emergency evacuation?
- 18 inches
- 24 inches
- 28 inches
- 36 inches (Correct answer)
Correct answer: 36 inches
A minimum 28-inch clear width is specified in many codes, but OSHA and NFPA guidance for construction sites typically recommend at least 36 inches for safe egress.
Question 2: Which chemical agent is prohibited for use in fighting fires involving reactive metals such as magnesium or titanium found on some construction sites?
- Class D dry powder agent
- Water (Correct answer)
- Carbon dioxide (CO2)
- Foam
Correct answer: Water
Water reacts violently with burning reactive metals, potentially causing explosions or spreading the fire; only Class D agents are appropriate.
Question 3: When multiple contractors share a construction site, who bears the primary responsibility for coordinating the site-wide Emergency Action Plan?
- Each subcontractor independently for their own crew
- The general contractor or controlling employer (Correct answer)
- The local fire authority having jurisdiction
- OSHA's area office upon request
Correct answer: The general contractor or controlling employer
The general contractor, as the controlling employer, is responsible for coordinating a unified EAP across all subcontractors on a multi-employer site.
Question 4: A propane torch used for roofing ignites a structural member. This fire is BEST classified as which type?
- Class A only
- Class B only
- Class A and Class B combined (Correct answer)
- Class C
Correct answer: Class A and Class B combined
If both the structural wood (Class A) and propane fuel (Class B) are burning, the fire involves two classes simultaneously.
Question 5: What is the purpose of a 'Knox Box' installed at the entrance to a major construction project?
- To store worker emergency contact cards
- To provide fire departments keyed access without forced entry (Correct answer)
- To house the project's MSDS/SDS binder
- To contain emergency medical supplies
Correct answer: To provide fire departments keyed access without forced entry
A Knox Box is a secure key storage system that allows fire departments to access buildings or sites quickly without damaging doors or gates.
Question 6: Under OSHA 29 CFR 1926.151, temporary heating equipment on a construction site must be positioned at a minimum distance from combustible materials of:
- 12 inches
- 24 inches
- 36 inches
- As specified by the manufacturer's instructions (Correct answer)
Correct answer: As specified by the manufacturer's instructions
OSHA 1926.151 requires temporary heating equipment to be used per the manufacturer's instructions, which specify the minimum clearance from combustibles.
Question 7: During a confined space rescue emergency on a construction site, a non-entry rescue method is preferred primarily because:
- It is faster than sending rescuers inside
- It prevents additional casualties by keeping rescuers out of the hazardous atmosphere (Correct answer)
- It requires less equipment to execute
- OSHA mandates non-entry rescue for all confined space incidents
Correct answer: It prevents additional casualties by keeping rescuers out of the hazardous atmosphere
Non-entry rescue (using retrieval systems) protects would-be rescuers from the same atmospheric or physical hazards that may have incapacitated the victim.
CHST CHST - Construction Health and Safety Technician Emergency and Fire Preparedness Questions and Answers 5
What is the recommended minimum clear width of an egress path on an active construction site to accommodate emergency evacuation?