2,2-Dichloro-1,1,1-trifluoroethane (HCFC-123)

Older centrifugal chillers and some industrial cleaning/processing uses; produced and handled by HVAC and chemical industries [1][2].

Breathing leaked gas during equipment operation or maintenance, especially in poorly ventilated mechanical rooms; accidental releases at workplaces; rare community exposure near industrial sites [1].

Short-term exposure can cause dizziness, headache, coughing, and eye/skin irritation; very high levels can displace oxygen and lead to fainting, and liquid contact can cause frostbite. Repeated or high exposures can injure the liver and affect heart rhythm. Environmentally, it depletes ozone and contributes to climate change [1][2].

HVAC/chiller technicians, building engineers, workers in enclosed or low-lying spaces, and people with existing heart or liver disease [1].

Maintain and retrofit equipment, ensure good ventilation and leak detection, follow safe work practices and PPE, monitor confined spaces, and never vent refrigerants; use certified technicians per EPA rules [1][2].