← All chemicals

CAS 354-11-0

1,1,1,2-Tetrachloro-2-fluoroethane (HCFC-121a)

HCFC-121a is a man‑made hydrochlorofluorocarbon used in older cooling systems, foam production, and cleaning/solvent applications. At high levels it can harm your health and it damages the ozone layer, so its use is being phased down in many countries [1][2].

Where It Comes From

Manufacturing and use of HCFCs; leaks from refrigeration/AC and foam equipment; releases during servicing or improper disposal of older systems [1].

How You Are Exposed

Breathing air where it leaks (home, workplace), during equipment maintenance or charging, or near industrial sites; liquid contact during handling [2].

Why It Matters

Short-term effects can include dizziness, headache, and nausea; very high levels can displace oxygen, trigger irregular heartbeat, and cause unconsciousness; liquid can cause frostbite. It also depletes ozone and contributes to climate warming [2][1].

Who Is at Risk

HVAC/refrigeration and foam workers, technicians and first responders, people in small or poorly ventilated spaces, and those with heart conditions or on certain stimulants/epinephrine-type drugs [2].

How to Lower Your Exposure

Use certified technicians, fix leaks promptly, ventilate work areas, avoid confined-space releases, follow PPE/handling instructions, and transition to non‑ozone‑depleting alternatives; dispose of old equipment properly [1][2].

References

  1. [1]U.S. EPA. Phaseout of Hydrochlorofluorocarbons (HCFCs). https://www.epa.gov/ods-phaseout
  2. [2]U.S. EPA. Refrigerant Safety (Section 608). Health and safety hazards of refrigerants. https://www.epa.gov/section608/refrigerant-safety

Track your exposure to 1,1,1,2-Tetrachloro-2-fluoroethane (HCFC-121a)

Pollution Profile maps your lifetime exposure history to EPA-tracked chemicals.

Get early access

We use cookies and analytics to understand how people use Pollution Profile and improve the experience. We never sell your data. Learn more.