CFC Refrigerant Cylinder & Storage Safety 2 — Questions and Answers
Question 1: What is the maximum allowable filling density (percent of water capacity by weight) for a DOT-39 non-refillable refrigerant cylinder?
- 60%
- 80%
- The percentage listed on the cylinder label (Correct answer)
- 125%
Correct answer: The percentage listed on the cylinder label
DOT-39 cylinders must not be filled beyond the filling density specified on the cylinder's label, which varies by refrigerant type.
Question 2: Which color is used to identify cylinders containing R-410A refrigerant under the ARI color-coding standard?
- Light blue (sky)
- Rose/pink (Correct answer)
- Orange
- Green
Correct answer: Rose/pink
R-410A cylinders are color-coded rose/pink under the ARI (now AHRI) standard to help technicians identify the refrigerant.
Question 3: A technician finds a refrigerant cylinder with no label. What is the correct action?
- Smell the cylinder valve to identify the refrigerant
- Use the cylinder if the color matches a known refrigerant
- Treat the cylinder as unknown and take it out of service (Correct answer)
- Weigh the cylinder to determine contents
Correct answer: Treat the cylinder as unknown and take it out of service
An unlabeled cylinder must be removed from service because the contents cannot be positively identified, posing safety and regulatory risks.
Question 4: What type of valve is required on all DOT cylinders used to transport refrigerant to prevent accidental release during transport?
- Ball valve
- Needle valve
- Protective cap or collar over the valve (Correct answer)
- Pressure-relief valve only
Correct answer: Protective cap or collar over the valve
DOT regulations require that cylinder valves be protected by a cap or collar to prevent accidental opening or damage during transportation.
Question 5: When storing refrigerant cylinders outdoors, which precaution is MOST important to prevent pressure buildup?
- Store cylinders valve-side down
- Keep cylinders in direct sunlight to monitor for leaks
- Shade cylinders from direct sunlight and heat sources (Correct answer)
- Chain cylinders horizontally to a wall
Correct answer: Shade cylinders from direct sunlight and heat sources
Shading cylinders prevents solar heat gain, which can raise internal pressure and risk cylinder failure or pressure-relief discharge.
Question 6: Which federal agency regulates the design, manufacture, and transportation of refrigerant cylinders?
- EPA
- OSHA
- DOT (Department of Transportation) (Correct answer)
- NFPA
Correct answer: DOT (Department of Transportation)
The U.S. Department of Transportation (DOT) sets standards for cylinder construction, testing, and labeling under 49 CFR.
Question 7: A recovery cylinder's pressure gauge reads higher than expected at room temperature. What should the technician do FIRST?
- Open the valve slightly to bleed pressure
- Check the cylinder for contamination or mixed refrigerants (Correct answer)
- Immediately dispose of the cylinder in a dumpster
- Weld the valve shut to prevent leaks
Correct answer: Check the cylinder for contamination or mixed refrigerants
Abnormally high pressure can indicate mixed refrigerants or non-condensable gas contamination, which must be investigated before further use.
CFC Refrigerant Cylinder & Storage Safety 2
What is the maximum allowable filling density (percent of water capacity by weight) for a DOT-39 non-refillable refrigerant cylinder?