Which type of refrigerants require special handling due to their flammable nature according to classification?

B2 and B3 class refrigerants are designated as flammable refrigerants, meaning they possess the potential to ignite easily in certain conditions. This classification requires special handling procedures due to their increased risk in both storage and application. For instance, appropriate infrastructure, such as proper ventilation and equipment designed to mitigate ignition risks, is necessary when dealing with these refrigerants.

Additionally, the training and awareness of personnel working with B2 and B3 refrigerants are crucial to ensure safety and compliance with regulations. This classification is based on the properties of these refrigerants, as they can create hazardous situations if not managed correctly. Thus, stringent guidelines and codes exist to address these risks, ensuring the safe usage of flammable refrigerants in HVAC applications.