EPA 609 Cheat Sheet 2026

The 30 highest-yield EPA 609 facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. What is the primary function of the compressor in an MVAC system? → To pressurize refrigerant vapor and circulate it through the system
2. Which method is recommended for detecting refrigerant leaks? → Using an electronic leak detector, UV dye, or soapy water solution
3. A sight glass showing bubbles in an R-134a system indicates: → The system may be low on refrigerant
4. What is a typical low-side pressure reading for a properly charged R-134a MVAC system at idle? → 25–45 psi
5. To purchase refrigerant in containers larger than 2 pounds, a technician must show proof of: → EPA Section 609 technician certification
6. What class of refrigerant is R-134a? → HFC
7. What does MSDS (now called SDS) provide for refrigerants? → Safety data including hazards, first aid, storage, and disposal information
8. What is 'reclaimed' refrigerant? → Refrigerant sent to a certified facility and processed to meet AHRI 700 purity standards
9. According to EPA Section 609, recovery equipment must remove what percentage of refrigerant from an MVAC system? → At least 90%
10. What is a typical high-side pressure reading for a properly charged R-134a MVAC system? → 150–250 psi
11. What is the ozone depletion potential (ODP) of R-134a? → 0.0
12. The high-pressure side of an MVAC system runs between which components? → Compressor outlet to evaporator inlet (through condenser)
13. What type of oil was used in R-12 MVAC systems? → Mineral oil
14. What does a 'decay test' after evacuation check for? → Whether the system holds vacuum, indicating it is leak-free before recharging
15. What color are R-12 refrigerant cylinders? → White
16. What is the boiling point of R-134a at atmospheric pressure? → -26.3°F (-32.4°C)
17. Which refrigerant replaced R-12 as the standard for MVAC systems in vehicles manufactured after 1994? → R-134a
18. What must technicians do if they discover that a vehicle's A/C system contains a refrigerant other than what is labeled? → Recover it into a separate cylinder for contaminated refrigerant
19. What hazardous gas can form when refrigerant contacts an open flame or very hot surface? → Phosgene or hydrofluoric acid gas
20. What does 'refrigerant venting' mean in the context of EPA regulations? → Intentionally or knowingly releasing refrigerant into the atmosphere
21. Abnormally LOW high-side pressure combined with abnormally LOW low-side pressure most likely indicates: → Insufficient refrigerant due to a system leak
22. What symptom indicates possible refrigerant overexposure? → Dizziness, headache, or irregular heartbeat
23. What is the purpose of low-loss fittings on service hoses? → To minimize refrigerant release when connecting and disconnecting hoses
24. How long is an EPA Section 609 certification valid? → Indefinitely — it does not expire
25. Recovered refrigerant that is contaminated with moisture or other refrigerants should be: → Sent to a certified reclaimer for processing
26. Equipment certified to SAE J2788 for R-134a may be used for R-1234yf service: → No — R-1234yf requires separate dedicated equipment certified for that refrigerant
27. Before performing a leak check on an MVAC system, the technician should first: → Run the A/C for several minutes to pressurize all components
28. Which term describes the process where a refrigerant blend separates into its component gases during a leak? → Fractionation
29. What type of container must recovered refrigerant be stored in? → DOT-approved recovery cylinders that are clearly labeled
30. What causes abnormally HIGH low-side pressure and HIGH high-side pressure in an MVAC system? → Overcharge or condenser cooling failure