Related by context. Frequent words. (Click for all words.) 61 propane tank 58 welding torch 57 gallon propane tank 55 exhaust vent 55 gasoline vapors 54 air compressor 53 air conditioning duct 53 propane torch 53 propane cylinders 52 vapor cloud 52 extinguisher 52 transformer 52 Firefighters doused 51 vacuum hose 51 acetylene 51 electrical transformer 51 highly flammable liquid 51 flammable gases 51 flammable substance 50 exhaust pipe 50 welding 50 propane heater 50 propane leak 50 copper tubing 50 hose 50 sprayed foam 50 Upon arrival firefighters 50 propane tanks 50 LPG cylinder 49 manhole cover 49 fire extinguisher 49 engine compartment 49 electrical wires 49 ventilation ducts 49 thinners 48 poisonous fumes 48 bilge pump 48 Hydrochloric acid 48 Anhydrous ammonia 48 chemical vapors 48 toxic fumes 48 unattended candle 48 freon 48 drip pan 47 potassium hydroxide 47 electrical malfunction 47 oily substance 47 backdraft 47 radiator 47 kerosene heater 47 pipe 47 angle grinder 47 nozzle 47 water heater 47 cannisters 47 odorless colorless gas 47 propane grill 47 gas canister 47 liquid propane 47 driver's side 47 propane 47 oily residue 47 insulation foam 47 deep fat fryer 47 metal grate 46 noxious gases 46 Compressed air 46 compressed air 46 anhydrous ammonia 46 ignition 46 manhole 46 electrical 46 valve stems 46 electrical arcing 46 highly inflammable 46 firebox 46 copper piping 46 furnace 46 smoldering cigarette 46 highly flammable 46 transformer exploded 46 metal shards 46 backhoe operator 46 muffler 46 electrical wiring 46 hydrogen fluoride 46 ductwork 46 ammonia 46 fumes 45 pipe wrench 45 sump 45 muriatic acid 45 properly ventilated 45 fuel injector 45 oxygen tank 45 electrical socket 45 windshield washer fluid 45 tanker truck 45 extension cord 45 carbon monoxide fumes 45 grabbed fire extinguisher