Do electric or propane radiant heaters in the shop pose a safety hazard considering all of the dust in the air?
Carol Reed: From an explosion standpoint, probably not, assuming there are no flammable vapors. A propane radiant heater has its flame isolated from the radiant heating environment, so there should be no problem. If there is an open flame, then we have a different kettle of fish.
John Brock: Dust isn’t a big flash hazard unless it is very concentrated, dry, and there is an ignition source. In a home shop, it’s more of a health hazard and irritant than anything else. If the dust were so thick as to be a flash problem, you wouldn’t be able to see anyway. A larger problem is carbon monoxide from the burning propane. If your heater is vented so its exhaust gasses are routed outside, then propane is fine.