Which refrigerant has a safety classification of B-1?

• A. HFC-134a (R-134a)
• B. HFC-410A (R-410A)
• C. HFC-123 (R-123)
• D. HCFC-22 (R-22)

Answer: (C)

The refrigerant HFC-123 (R-123) is classified as B-1 due to its characteristics pertaining to flammability and toxicity. The safety classification system used for refrigerants categorizes them based on their potential risks. The B classification indicates that the refrigerant is considered to have low flammability (B-1 specifically indicates that it is non-flammable in air at room temperature under normal conditions) and moderate toxicity.

This classification is important for handling, storage, and application of refrigerants in various systems, especially in commercial and industrial settings where safety is paramount. B-1 refrigerants can still present some health risks, which necessitates awareness and adherence to safety protocols when using them in HVAC systems.

In contrast, the other refrigerants mentioned have different safety classifications that do not match B-1, making HFC-123 the correct choice in this context. Each of those alternatives may present specific hazards or different flammability characteristics that classify them differently in the safety classification system.