Why are chlorofluorocarbon refrigerants considered harmful?

Chlorofluorocarbon (CFC) refrigerants are considered harmful primarily because they contain chlorine, which plays a significant role in depleting the ozone layer. When CFCs are released into the atmosphere, they eventually reach the stratosphere where UV radiation breaks them down, releasing chlorine atoms. These chlorine atoms can then react with ozone (O3) molecules, leading to the thinning of the ozone layer, which protects the Earth from harmful ultraviolet radiation. This depletion can result in increased skin cancer rates and other environmental issues.

While factors such as cost, efficiency, and behavior in systems are important to consider when evaluating refrigerants, the critical environmental impact of chlorine on ozone destruction is the primary reason why CFCs are hazardous. This understanding highlights the importance of transitioning to more environmentally friendly refrigerants that do not contain ozone-depleting substances.