Safe Handling and Recovery of Refrigerants Flashcards

What is the maximum amount a refillable recovery cylinder should be filled with liquid refrigerant?

Answer: 80% of its capacity

Recovery cylinders should not exceed 80% liquid fill so there is room for liquid expansion as temperature rises.

What color scheme identifies a DOT-approved refrigerant recovery cylinder?

Answer: Gray body with a yellow top

Recovery cylinders are painted gray with yellow shoulders/tops to distinguish them from virgin refrigerant containers.

Which gas should be used to pressurize a refrigeration system when checking for leaks?

Answer: Dry nitrogen

Dry nitrogen is inert and dry, while oxygen or compressed air can cause explosions when mixed with compressor oil.

When pressurizing a system with nitrogen from a high-pressure cylinder, what must be installed on the nitrogen cylinder?

Answer: A pressure regulator and relief valve

Nitrogen cylinders can exceed 2,000 psig, so a pressure regulator and relief valve protect the system from overpressurization.

Exposing refrigerants such as R-22 to an open flame or a very hot surface can produce which highly toxic gas?

Answer: Phosgene

Decomposition of CFC and HCFC refrigerants at high temperatures can form phosgene and acids such as hydrochloric and hydrofluoric acid.

Why is a large refrigerant leak in an enclosed mechanical room dangerous to technicians?

Answer: Refrigerant vapor is heavier than air and can displace oxygen, causing asphyxiation

Most refrigerant vapors are heavier than air and can displace oxygen in low or enclosed spaces, leading to suffocation.

What personal protective equipment is required at minimum when handling refrigerant cylinders and connecting hoses?

Answer: Safety glasses and protective gloves

Safety glasses and gloves protect the eyes and skin from liquid refrigerant, which can cause frostbite on contact.