Automobile Air-conditioning: REFRIGERANT SAFETY PRECAUTIONS

Air-conditioning (A/C) service, in many ways, is different from service to other parts of the vehicle. Although there are few parts in the system, each component has a specific purpose and service procedure.

R-12 should be stored and sold in white containers, whereas R-134a should be stored in light blue containers.

That by itself is not a big deal. The challenge with the A/C is how it operates. The system operates on changes of refrigerant pressure. There are many things that can cause the pressure to change; some are part of the system, some are part of the environment, and some of them are faults or bad components in the system.

There are some precautions when you work with refrigerants.

1. Always work in a well-ventilated and clean area. Refrigerants are colorless and invisible. Refrigerant is heavier than oxygen and will displace it in a confined area. Avoid breathing the refrigerant vapors. Exposure to refrigerant may irritate your eyes, nose, and throat.
2. Refrigerant evaporates quickly when it is exposed to the atmosphere. It will freeze anything it contacts. If liquid refrigerant gets in your eyes or on your skin, it can cause frostbite. Never rub your eyes or skin if refrigerant has contacted these areas. Immediately flush the exposed areas with cool water for 15 minutes and seek medical help. Also check the MSDS for the refrigerant to identify other safety-related procedures.
3. An A/C system’s high pressure can cause severe injury to your eyes and/or skin if a hose were to burst. Always wear eye protection when working around the A/C system and refrigerant. It is also advisable to wear protective gloves and clothing.
4. Never use R-134a in combination with compressed air for leak testing. Pressurized R-134a in the presence of oxygen may form a combustible mixture. Never introduce compressed air into R-134a containers (empty or full ones), A/C systems, or A/C service equipment.
5. Be careful when handling refrigerant containers. Never drop, strike, puncture, or burn the containers. Always use DOT-approved refrigerant containers.
6. Never expose A/C system components to high temperatures. Heat will cause the refrigerant’s pressure to increase. Never expose refrigerant to an open flame.
7. Never overfill refrigerant containers. The filling level of the container should never exceed 60 percent of the container’s gross weight rating. Always store refrigerant containers in temperatures below 125 ° F ( 52 ° C ) and keep them out of direct sunlight.
8. Refrigerant comes in 30 - and 50 - pound cylinders. Keep the drums in an upright position. Make sure that valves are protected by safety caps when the drums are not in use. Avoid dropping the drums. Handle them carefully.
9. R -12 should be stored and sold in white containers, whereas R-134a should be stored in light blue containers. R-12 and R-134a should never be mixed. If the two refrigerants are mixed, contamination will occur and may result in A/C system failure. Separate service equipment should be used for the different refrigerants.
10. To prevent cross-contamination, identify whether the A/C system being worked on uses R-12 or R-134a. Check the fittings in the system; all R-134a-based systems use 1 /2 -inch 16 ACME threaded fittings and quickdisconnect service couplings. Most R-134a systems can be identified by underhood labels clearly stating that R-134a is used. Most manufacturers identify the type of refrigerant used by labeling the compressor. Also look for a label with the words, “CAUTION—SYSTEM TO BE SERVICED BY QUALIFIED PERSONNEL.” This label or plate can be found under the hood near a component of the system. This label also indicates what kind refrigerant is used the required quantity to fill the system, and the type of refrigerant oil.
11. Before storing refrigerant in a tank, evacuate the tank before filling it. Tank pressure should never exceed the maximum allowable pressure as indicated on the tank.