As the U.S. tries to phase out a polluting refrigerant that is used in millions of air conditioners across the country, unapproved coolant is popping up on the market — with potentially dangerous consequences.
The FBI is warning people to be on alert for refrigerant substitutes that have not been approved by the Environmental Protection Agency. Some contain propane, which is flammable and can explode or catch fire if, for example, a technician servicing an air conditioner gets too close to the coolant while soldering. So far, the explosions have been rare.