HVAC - EPA Certification Practice Exam 2025 - Free EPA Certification Practice Questions and Study Guide

The refrigerant type that is primarily known for having a negative effect on ozone depletion is chlorofluorocarbons (CFCs). CFCs contain chlorine, which is released into the atmosphere when these substances are used or leak. Once in the stratosphere, chlorine atoms can break down ozone (O3) molecules, leading to the depletion of the ozone layer. The ozone layer is critical for protecting the Earth from harmful ultraviolet (UV) radiation.

HFCs (hydrofluorocarbons) and HCFCs (hydrochlorofluorocarbons) do not contain chlorine and therefore do not contribute to ozone depletion in the same manner as CFCs. HFCs are considered more environmentally friendly since they do not harm the ozone layer, although they may still have high global warming potential.

HCFCs were developed as transitional substitutes for CFCs and are less harmful to ozone than CFCs, but they still contain some chlorine and can still contribute to ozone depletion, albeit to a lesser extent. Therefore, while both HCFCs and HFCs are a concern in other environmental contexts, they are not the primary concern regarding ozone depletion as CFCs are.

Choosing CFC