Why can a large R-134a leak in an enclosed equipment room be dangerous even though R-134a has low toxicity?
Safety · EPA 608 Type II. The correct answer, and the reasoning behind it.
Hermetic compressors under vacuum and other high-pressure hazards.
The question
Why can a large R-134a leak in an enclosed equipment room be dangerous even though R-134a has low toxicity?
- R-134a burns easily in air
- R-134a turns into carbon monoxide
- Its heavy vapor can displace the oxygen in the roomCorrect answer
- R-134a reacts with oxygen in the room to form ozone
Why “Its heavy vapor can displace the oxygen in the room” is correct
Most refrigerant vapors are heavier than air. A major leak can collect in an enclosed room and push out the oxygen, which can cause suffocation without warning. That is the hazard behind EPA's oxygen-deprivation topic; current ASHRAE Standard 15 guards against it with a refrigerant detector set no higher than the refrigerant's exposure limit (1,000 ppm for R-134a).
Source: EPA: Test Topics; ASHRAE 15-2016 Addendum c (detector set point at OEL)
Why the other answers are wrong
- R-134a burns easily in air — R-134a is not classed as a flammable refrigerant.
- R-134a turns into carbon monoxide — R-134a does not turn into carbon monoxide.
- R-134a reacts with oxygen in the room to form ozone — Refrigerants do not create ozone by reacting with oxygen.
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