R-123 falls under which code group in ASHRAE Standard 34?

R-123 is classified as a refrigerant under the ASHRAE Standard 34 code group B1. The classification of refrigerants in this standard is based on their toxicity and flammability, which helps in determining the safety measures that need to be implemented when using or handling these substances.

The B group refers to refrigerants that have been determined to have higher toxicity levels but are non-flammable. Within this group, B1 is specifically designated for refrigerants that have low toxicity and do not pose a significant risk to human health under normal use conditions. R-123, being a refrigerant with manageable health risk, fits well into this classification.

In contrast, other code groups under ASHRAE Standard 34 cover various categories, such as A1 for non-toxic and non-flammable refrigerants, and B2 for those with moderate toxicity. Understanding these classifications is crucial for ensuring proper safety protocols in refrigeration applications.