What’s the real-world flammability risk of A2Ls in occupied spaces vs garages and basements, and how do contractors mitigate during brazing?
A2L flammability isn’t a big deal. Installers keep things safe by using nitrogen, being careful when brazing, and making sure there’s good air flow. This means the risk in homes and garages stays super low.
A2L refrigerants are mildly flammable (lower flammability than typical hydrocarbons) so the real-world risk in occupied spaces is low if charge limits and ventilation per B52 are met; garages and basements are slightly higher risk due to confined air and potential ignition sources. Contractors mitigate during brazing by evacuating refrigerant from the line, purging with nitrogen, keeping sparks away from leaked refrigerant, and using ventilation and leak detection while brazing.