What safety measure must be observed when changing refrigerant in an ACU?

When changing refrigerant in an ACU, the primary safety measure that must be observed is to use a refrigerant recovery machine to properly capture and contain the old refrigerant. Releasing refrigerant into the atmosphere is illegal and environmentally damaging due to its ozone-depleting and global warming potential. The recovery machine extracts the refrigerant from the ACU system and stores it in a sealed container for proper disposal or recycling. Technicians must also wear appropriate personal protective equipment (PPE), including gloves and eye protection, to prevent skin contact or inhalation of refrigerant vapors, as these can cause frostbite and respiratory irritation. The work area should be well-ventilated to minimize the concentration of refrigerant vapors in case of a leak. Following these procedures ensures that the refrigerant is handled safely and responsibly, minimizing the risks to personnel and the environment.