EPA Section 608 Universal Certification ExamCoreMedium
Which of the following refrigerants has the lowest Ozone Depletion Potential (ODP)?
- AR-502
- BR-22
- CR-12
- DR-134a
Show answer & explanationAnswer & explanation
Correct answer: D. R-134a
R-134a is a Hydrofluorocarbon (HFC), which contains no chlorine. Therefore, it has an Ozone Depletion Potential (ODP) of zero. R-12 (CFC), R-22 (HCFC), and R-502 (CFC/HCFC blend) all contain chlorine and thus have non-zero ODPs.
Why the other options are wrong
- A. R-502 is a blend containing CFC and HCFC, thus it has a high ODP.
- B. R-22 is an HCFC with a significant ODP (0.05).
- C. R-12 is a CFC with a very high ODP (1.0).
Refrigerant ODP
Ozone Depletion Potential (ODP) is a measure of how much a given chemical contributes to ozone layer depletion. CFCs have the highest ODP, followed by HCFCs, while HFCs and HFOs have an ODP of zero.
- CFCs: High ODP (e.g., R-12 = 1.0).
- HCFCs: Lower ODP than CFCs (e.g., R-22 = 0.05).
- HFCs: ODP of zero (e.g., R-134a, R-410A).
- HFOs & Natural: ODP of zero.
Memory trick: No Chlorine, No Ozone Destruction.