Safety and Regulatory Compliance
Venting and certification
Section 608 prohibits knowingly venting ozone-depleting refrigerants and their substitutes during service, maintenance, repair, or disposal. Only de minimis releases during good-faith repair are excused. Technicians must hold the appropriate certification, and Type II is the credential for high-pressure equipment.
Cylinder safety
The most tested safety fact: never fill a cylinder above 80% of its capacity by weight. Liquid refrigerant expands as it warms; a full cylinder becomes a hydraulic bomb. Use DOT-approved cylinders, check the hydrostatic test date, and never heat a cylinder with an open flame or above 125°F - use warm water or a heating blanket.
Pressure testing and mixing
Use dry nitrogen, never oxygen or compressed air, to pressure-test or leak-check a system; oil plus oxygen can ignite. Never mix refrigerants in a cylinder. Never use a refrigerant cylinder as a pressure vessel for air. Every cylinder must be labeled with its contents.
Personal and site safety
Wear gloves and eye protection - liquid refrigerant causes frostbite. Refrigerant vapor is heavier than air and displaces oxygen in pits and basements, so ventilate before entering. Keep records of refrigerant transactions and leak-repair actions for three years.
Rule of thumb
80% fill, 125°F maximum, 3 years of records. Those three numbers answer a surprising share of compliance questions.