EPA 608 Type II · Safety · Medium
Why must you never pressurize a refrigeration system with oxygen or compressed air?
Answer: D. It can cause an explosion when mixed with compressor oil.
- AIt will freeze the moisture inside the system.
- BIt will cause a false reading on the micron gauge.
- CIt will instantly degrade the copper piping.
- DIt can cause an explosion when mixed with compressor oil.✓ Correct
Why D is right
Oxygen or compressed air mixed with compressor oil under pressure becomes highly explosive. Always use dry nitrogen for pressurizing or leak testing.
More Type II questions
- Can you pipe two pressure relief valves in series?
- Why must you never start a hermetic compressor while it is in a deep vacuum?
- What service pressure rating must a recovery cylinder have to hold R-410A?
- Recovering R-454B, an A2L refrigerant, requires what kind of recovery machine?
- What gas is strictly used with a trace amount of refrigerant to leak test a system?
Go deeper with the study guide A2L Refrigerants and the R-410A Transition: A Tech’s Guide, try the free 10-question test or browse all EPA 608 practice questions.
A practice question written for study, checked against 40 CFR Part 82, Subpart F. It is not an official EPA exam question, and this site is not affiliated with the U.S. EPA.