January 2000. Depending on the rate of depletion of the ozone layer, these timetables could be accelerated.

As a result of the Clean Air Act of 1990, there has been a determined effort by manufacturers to develop alternative refrigerants to replace those to be discontinued. CFCs, R-11, and R-12, primarily used in chillers, residential, and automotive refrigeration, can be substituted with HCFC R-123 and HFC R-134a. Future replacements include HCFC R-124 in place of CFC, R-114, in marine chillers, and HFC R-125, in place of CFC R-502, used in stores and supermarkets.

These replacement refrigerants have slightly different chemical and physical properties; thus they cannot just be "dropped" into a system designed to use CFCs. Loss of efficiency and improper operation could be the result. When changing the refrigerant in an existing system, parts of the system specifically designed to operate with a CFC refrigerant may need to be replaced or retrofitted to accommodate the new refrigerant.

Q13. What are CFCs and HCFCs?

Q14. What can happen if improper refrigerant is used in a refrigeration system?

Q15. What types of refrigerants are to be phased out by the Clean Air Act in 2030?

Q16. What refrigerant has been developed to replace R-12?

REFRIGERANT SAFETY

Learning Objective: Recall the safety requirements for handling and storage of refrigerants and refrigerant cylinders.

Safety is always paramount and this is especially true when you are working with refrigerants. Major safety concerns are discussed in this section.

PERSONAL PROTECTION

Since R-12, R-22, and R-502 are nontoxic, you will not have to wear a gas mask; however, you must protect your eyes by wearing splashproof goggles to guard against liquid refrigerant freezing the moisture of your eyes. When liquid R-12, R-22, and R-502 contact the eyes, get the injured person to the medical officer at once. Avoid rubbing or irritating the eyes. Give the following first aid immediately:

Drop sterile mineral oil into the eyes and irrigate them.

Wash the eyes when irrigation continues with a weak boric acid solution or a sterile salt solution not to exceed 2 percent salt.

Should the refrigerant contact the skin, flush the affected area repeatedly with water. Strip refrigerant-saturated clothing from the body, wash the skin with water, and take the patient immediately to the dispensary. Should a person be overcome in a space which lacks oxygen due to a high concentration of refrigerant, treat the victim as a person who has experienced suffocation; render assistance through artificial respiration.

HANDLING AND STORAGE OF REFRIGERANT CYLINDERS

Handling and storage of refrigerant cylinders are similar to handling and storage of any other type of compressed gas cylinders. When handling and storing cylinders, keep the following rules in mind:

Open valves slowly; never use any tools except those approved by the manufacturer.

Keep the cylinder cap on the cylinder unless the cylinder is in use.

When refrigerant is discharged from a cylinder, immediately weigh the cylinder.

Record the weight of the refrigerant remaining in the cylinder.

Ensure only regulators and pressure gauges designed for the particular refrigerant in the cylinder are used.

Do use different refrigerants in the same regulator or gauges.

Never drop cylinders or permit them to strike each other violently.

Never use a lifting magnet or a sling. A crane may be used when a safe cradle is provided to hold the cylinders.

Never use cylinders for any other purpose than to carry refrigerants.

Never tamper with safety devices in the cylinder valves.

Never force connections that do not fit. Ensure the cylinder valve outlet threads are the same as what is being connected to it.