HVAC Safety Practices 2 — Questions and Answers
Question 1: When working with refrigerants, which type of gloves should HVAC technicians wear to prevent frostbite?
- Leather work gloves
- Cryogenic or chemical-resistant gloves (Correct answer)
- Latex disposable gloves
- Cotton canvas gloves
Correct answer: Cryogenic or chemical-resistant gloves
Cryogenic or chemical-resistant gloves protect against refrigerant contact, which can cause severe frostbite at extremely low temperatures.
Question 2: What is the minimum safe distance a technician should maintain from an electrical panel before beginning work on an HVAC system connected to it?
- No specific distance is required if breakers are off
- At least 1 foot with insulated tools only
- Follow NFPA 70E arc flash boundary requirements based on voltage (Correct answer)
- At least 6 feet at all times
Correct answer: Follow NFPA 70E arc flash boundary requirements based on voltage
NFPA 70E establishes arc flash protection boundaries that vary based on system voltage and available fault current.
Question 3: Which color label on a refrigerant cylinder indicates it contains a blend/mixed refrigerant?
- A solid color assigned to that specific blend (Correct answer)
- Always red
- Yellow and orange stripes
- Always gray
Correct answer: A solid color assigned to that specific blend
ARI/AHRI assigns specific colors to individual refrigerants and blends, so each refrigerant type has its own designated cylinder color.
Question 4: A technician is about to braze copper refrigerant lines in a confined mechanical room. What is the MOST critical safety precaution?
- Ensure the system is fully charged with refrigerant
- Provide adequate ventilation and have a fire extinguisher ready (Correct answer)
- Wear only a dust mask for fume protection
- Work quickly to minimize heat exposure time
Correct answer: Provide adequate ventilation and have a fire extinguisher ready
Brazing produces toxic fumes and open flame, requiring adequate ventilation and a fire extinguisher immediately accessible.
Question 5: What does OSHA require when an HVAC technician must work on a rooftop unit within 6 feet of an unguarded roof edge?
- A warning line system alone is sufficient
- Fall protection such as guardrails, safety nets, or personal fall arrest systems (Correct answer)
- A spotter on the ground watching the technician
- Written acknowledgment of the risk before starting work
Correct answer: Fall protection such as guardrails, safety nets, or personal fall arrest systems
OSHA 29 CFR 1926.502 requires fall protection (guardrails, safety nets, or personal fall arrest) when within 6 feet of an unprotected edge.
Question 6: When recovering refrigerant from a system suspected to contain moisture contamination, what additional hazard must the technician consider?
- The refrigerant may ignite during recovery
- Acid formation that can damage the recovery machine and harm the technician (Correct answer)
- The refrigerant will expand to dangerous pressures
- Moisture makes refrigerant heavier and harder to recover
Correct answer: Acid formation that can damage the recovery machine and harm the technician
Moisture reacts with refrigerant to form hydrofluoric or hydrochloric acid, which can damage equipment and pose a chemical burn hazard.
Question 7: An HVAC technician smells a strong odor of rotten eggs near a gas furnace. What is the FIRST action to take?
- Light a match to identify the source of the leak
- Evacuate and call the gas utility — do not operate any electrical switches (Correct answer)
- Check the heat exchanger for cracks before leaving
- Turn off the furnace using its power switch
Correct answer: Evacuate and call the gas utility — do not operate any electrical switches
The rotten egg smell indicates a gas leak; evacuating immediately and calling the gas utility prevents ignition — electrical switches can spark and trigger an explosion.
HVAC Safety Practices 2
When working with refrigerants, which type of gloves should HVAC technicians wear to prevent frostbite?