Good ventilation is important when working around refrigeration equipment because modern refrigerants ______.

Good ventilation is crucial when working around refrigeration equipment primarily because modern refrigerants can be heavier than air, which can lead to dangerous situations. If a refrigerant leak occurs, the heavier-than-air gas may settle in low-lying areas and displace oxygen, creating an asphyxiation hazard for workers in enclosed or poorly ventilated spaces. Proper ventilation ensures that any accumulating gases are diluted and allows for a safe working environment.

In addition to this concern, some refrigerants may also pose toxicity risks. Choosing heavy gases as one of the hazards emphasizes the importance of ventilation, as the lack of it can lead to both asphyxiation and toxicity. Thus, while there are concerns about toxicity and unpleasant odors with certain refrigerants, the primary risk regarding heavy gases displacing oxygen in the presence of poor ventilation underscores the necessity of ensuring good airflow whenever refrigeration systems are being serviced.