New York City Refrigeration License Exam I Practice

Refrigerant safety classifications use two factors: health hazard and fire risk. The first letter indicates toxicity, with A meaning lower toxicity and B meaning higher toxicity. The number (or second indicator) shows flammability, where 1 means non-flammable and higher values indicate some level of flammability. The label that marks a refrigerant as having no flammability and lower toxicity is the safest category in this system, since it communicates both minimal health risk and no fire hazard. That’s why it’s the best fit for the question. Other categories imply some flammability or higher toxicity, so they don’t meet both conditions.