Handling Contaminated and Unfamiliar Automotive Refrigerants
It's clear to most automotive service technicians by now that buying and handling A/C refrigerants is a lot more complicated than it used to be. Even when R-12 was the only refrigerant in town, many A/C techs discovered systems that had been contaminated with air, R-22 or hydrocarbons such as propane and butane. Today, with new vehicles using R-134a refrigerant, and with an abundance of other R-12 substitutes reaching the market, the variety of refrigerants that techs may handle on the job is making A/C service more complicated than ever.
This document is designed to assist techs in determining how to identify, recover, and dispose of any contaminated refrigerants they may encounter. This document will also discuss what a tech should do with a substitute refrigerant that he has chosen not to work with or is unfamiliar to him. EPA intends to update this document whenever the Agency receives new information about potential solutions to the problems relating to contaminated or unfamiliar refrigerants.
A. Identifying refrigerants
EPA requires that when any vehicle is retrofitted from R-12, a label identifying the new refrigerant in the system must be placed under the hood, and new fittings that are unique to that refrigerant must be attached to the high- and low-side service ports of the A/C system. (For a complete discussion of these and other requirements, see the EPA fact sheet "Choosing and Using Alternative Refrigerants.") These EPA requirements obviously don't solve the entire refrigerant identification problem. Your shop could encounter a vehicle that has been retrofitted to another refrigerant but has not been properly relabeled, or a vehicle that has the right label, but highly contaminated refrigerant.
Checking refrigerant pressures does not guarantee that you will recognize that refrigerant is contaminated or is a brand that is unfamiliar to you. Unusual head pressures may tip you off that a system labeled to indicate that it has pure R-12 or R-134a in it actually is highly contaminated or contains another refrigerant altogether. However, you may also encounter a contaminated system, or a system that contains a blend refrigerant, that indicates pressures similar to those of pure R-12 or R-134a.
Purchasing a refrigerant identifier unit can help pinpoint many refrigerant identification problems, and EPA strongly recommends (but does not require) that techs obtain this equipment. You can use the identifier to confirm that the refrigerant your supplier is sending you is exactly what he says it is -- pure and uncontaminated. The equipment you choose will depend on what you plan to do once you discover that refrigerant in a vehicle is not pure R-12 or R-134a. If, for example, you decide to turn the customer with a contaminated system away, then a less-expensive identifier that simply tells you whether refrigerant is pure R-12 or R-134a ("go/no-go") may be sufficient for you.
However, a unit that can help you identify the chemical composition of the refrigerant more specifically can be an important diagnostic tool, so that the extra cost may be well worth it. Some models can identify flammable substances, which require special care and safe handling (see section B below). Some models can tell you how much air is in recycled refrigerant, so that you can use these models to determine whether the air purge cycle feature on your R-12 or R-134a recycling equipment is functioning properly. Excess air in an A/C system can lead to false readings in electronic low charge indicators in some vehicles; rapid clutch cycling and potential clutch failures; and noisy compressor operation. Finally, using this tool may build your customers' confidence in your diagnostic abilities.
Keep in mind that even the most sophisticated diagnostic units on the market today cannot properly identify all combinations of chemicals used in blend refrigerants. Diagnostic identifiers being sold today may be able to identify potential R-12 and R-134a contaminants such as air, R-22, and hydrocarbons, but many were not designed to identify R-124 and R-142b (chemicals that are components in many of the new substitutes), or to recognize particular chemical combinations as specific patented, marketed blend refrigerants. In the future, equipment manufacturers may develop equipment designed to identify all of the substitute refrigerants that are being marketed today.
Whether you are interested in purchasing a "go/no-go" unit or a diagnostic unit, check that the unit meets the SAE J1771 standard, which is an indication that the unit accurately identifies refrigerants. When claiming to meet this standard, manufacturers of identifier equipment are required to label the unit stating its level of accuracy.
If you are reluctant to invest in another piece of equipment, consider making an arrangement to borrow an identifier from a nearby service facility that has purchased one. That facility may agree to make its identifier available to you for a reasonable fee.
You may not wish to turn away a good customer who comes to the shop with contaminated R-12 or R-134a, or with a substitute refrigerant for which you have no dedicated recovery or recycling equipment. What do you do?
As a first step, the contaminated or unfamiliar refrigerant must be recovered. EPA prohibits venting any automotive refrigerants (including "unacceptable" refrigerants), no matter what combination of chemicals is in the refrigerant. The best way today that a tech can recover contaminated or unfamiliar refrigerant is to dedicate a recover-only unit to anything that is not pure R-12 or pure R-134a. Some equipment manufacturers may also be marketing new types of recover-only stations specifically designed to remove these refrigerants.
If the refrigerant you extract into a recovery unit contains a high level of flammable substances such as propane and butane, a fire hazard may result if the refrigerant comes into contact with an ignition source within the equipment. Whether you are purchasing a new piece of equipment to handle your contaminated and unfamiliar refrigerants, or you are converting a piece of existing equipment for this purpose, make sure you talk to your sales representative about what features have been incorporated into the equipment to guard against risks of ignition.
Refrigerant should be recovered into the standard DOT-certified, gray-with-yellow-top recovery tank, and if the tank is not equipped with a float valve (which serves as overfill protection), make sure it never gets filled beyond 60% of its gross weighted capacity, as specified in the SAE J1989 and J2211 standards.
If A/C service is not a large percentage of your business, then you may be reluctant to invest in another piece of recovery equipment. If this is the case, consider calling a local A/C specialty shop that may have the equipment necessary to service contaminated refrigerants or refrigerants that are unknown to you.
Once recovered, refrigerant should not be recycled on-site unless it is uncontaminated R-12 or R-134a. Recovering contaminated R-12 or R-134a refrigerant into recycling equipment may damage the equipment. In addition, EPA regulations currently prohibit technicians from recycling blend substitute refrigerants (contaminated or not). EPA is working with independent testing laboratories and with equipment manufacturers to determine whether it is possible to develop recycling equipment to service these blends that protects both the health or safety of the technician, and the integrity of the A/C system.
C. Storage and disposition of contaminated or unfamiliar refrigerants
Once the refrigerant has been recovered, if you can't recycle it, what do you do with it? The answer, naturally, is that it depends.
If the refrigerant in your "junk" tank contains significant amounts of flammable substances, it may be considered hazardous and you should make sure you follow any local ordinances that govern the storage of combustible mixtures. In addition, if your shop generates over 100 kilograms (220 pounds) of hazardous wastes per month (including used coolant, paint, rust removers, solvents, degreasers, and battery acids), then your shop must meet certain storage and transportation requirements under the Resource, Conservation and Recovery Act (RCRA). For more details, call the RCRA Hotline at (800) 424-9346 and ask for EPA publication 530-K-95-001, the 1996 update of "Understanding the Hazardous Waste Rules -- A Handbook for Small Businesses." You may also wish to check out the web site of the Coordinating Committee for Automotive Repair.
If the refrigerant in your "junk" recovery tank is a chemical "soup" -- either contaminated R-12 and R-134a, or a mixture of those contaminated refrigerants and some blend refrigerants that you are unfamiliar with -- then the contents should be reclaimed or destroyed. You should investigate all your options and pick the one that makes the most economic sense for you.
If you have a contract in place with a waste hauler, contact the hauler to see if they can handle the material. Waste haulers may require that the contents be identified first and may charge you for this identification procedure. They are most likely to send the tank to an incinerator for destruction. You may also want to contact one or more reclaimers, who will send the refrigerant off-site either for destruction, or for reclamation, which involves breaking it up into its chemical components and purifying each of the components.
Some reclaimers can handle tanks sent to them from anywhere in the nation. A reclaimer does not necessarily have to be located in your area.
Due to the expense involved in reclaiming, some reclaimers may not accept less than 500 or 1000 pounds of contaminated or mixed refrigerant. In addition, you should be aware that not all reclaimers have the technology to handle all contaminated or mixed refrigerants. However, if one tells you that he is not interested in receiving your tank, don't necessarily assume that the next reclaimer you call will say the same thing.
Before you enter into any agreement with either your waste hauler or a reclaimer, make sure you understand all of the costs involved; there may be separate charges for identifying the material, transporting it and destroying it. If you are responsible for shipping the tank, make sure that the hauler or reclaimer explains to you how to comply with any applicable DOT, state and local requirements relating to shipping.
EPA maintains a list of reclaimers that is available through the Hotline at 800/296-1996. EPA will update this fact sheet in the event that the Agency receives more specific information about which reclaimers will accept mystery mixtures of refrigerant.
If you have questions about disposing of specific blend refrigerants, call the refrigerant manufacturer. Most manufacturers of blend refrigerants have made arrangements with specific reclaimers to handle their used refrigerant. For a list of these telephone numbers, see the EPA fact sheet Choosing and Using Alternative Refrigerants.