CRST Safety Procedures & Environmental Regulations 3 — Questions and Answers
Question 1: What is the purpose of a refrigerant recovery machine's high-pressure cutout switch?
- To shut down the compressor when discharge pressure becomes dangerously high (Correct answer)
- To signal when the recovery cylinder is full
- To prevent refrigerant from flowing backward
- To regulate suction pressure during recovery
Correct answer: To shut down the compressor when discharge pressure becomes dangerously high
The high-pressure cutout protects the recovery machine's compressor from damage caused by excessively high discharge pressures.
Question 2: Under ASHRAE Standard 15, which refrigerant safety classification indicates the lowest toxicity and flammability?
- A1 (Correct answer)
- B2L
- A2
- B1
Correct answer: A1
Class A1 refrigerants have the lowest acute toxicity (Class A) and are non-flammable (Class 1), making them the safest classification.
Question 3: A technician is working in a confined space with a suspected refrigerant leak. What is the first action to take?
- Put on a respirator and begin identifying the leak
- Evacuate the space and ventilate before re-entry (Correct answer)
- Turn off all electrical equipment in the space
- Check the refrigerant type using a detector
Correct answer: Evacuate the space and ventilate before re-entry
Immediate evacuation and ventilation of the confined space is required before re-entry to prevent oxygen displacement or toxic exposure.
Question 4: Which EPA program requires technicians who purchase refrigerants in containers larger than 2 pounds to hold a valid certification?
- EPA Section 602
- EPA Section 605
- EPA Section 608 (Correct answer)
- EPA Section 612
Correct answer: EPA Section 608
EPA Section 608 requires technicians to be certified before purchasing or handling refrigerants in containers larger than 2 pounds.
Question 5: What is the primary hazard associated with using nitrogen to pressure-test a refrigeration system?
- Nitrogen reacts with refrigerant oil
- Overpressurization if pressure is not controlled (Correct answer)
- Nitrogen causes copper tubing to corrode
- Moisture introduction from nitrogen cylinders
Correct answer: Overpressurization if pressure is not controlled
Nitrogen is used at high pressures, and without a pressure regulator and relief valve, systems can be overpressurized, leading to catastrophic failure.
Question 6: What label information is required on a recovered refrigerant cylinder before it can be sent to a reclaimer?
- Only the technician's EPA certification number
- Refrigerant type, whether it contains oil, and whether it is mixed with other refrigerants (Correct answer)
- Only the customer's name and service date
- System operating pressure and temperature only
Correct answer: Refrigerant type, whether it contains oil, and whether it is mixed with other refrigerants
Recovered refrigerant cylinders must be labeled with the refrigerant type, oil contamination status, and whether the refrigerant is a mixture.
Question 7: Which condition makes it legal under EPA Section 608 to vent a small amount of refrigerant during service?
- When the amount is less than 1 pound
- When the refrigerant is R-410A
- De minimis releases that occur during good-faith repair attempts (Correct answer)
- When the system charge is under 5 pounds
Correct answer: De minimis releases that occur during good-faith repair attempts
EPA allows de minimis refrigerant releases that unavoidably occur during good-faith attempts to recover, recycle, or reclaim refrigerants.
CRST Safety Procedures & Environmental Regulations 3
What is the purpose of a refrigerant recovery machine's high-pressure cutout switch?