A controlled burn should have/would have taken care of the gasses going into the air, I believe. This could have just been a burn--period. I don't know if hydrogen chloride and phosgene would burn "off" and not be harmful after being subjected to heat. This guy sounds mad and who wouldn't be to see something like that. Who knows what problems they will have in the near to far future? I did copy this from a phosgene chemical website, it doesn't sound too good: EXPLOSION HAZARDS: Phosgene is not combustible. Containers may explode when heated. Ruptured cylinders may rocket. FIRE FIGHTING INFORMATION: Phosgene (CG) is non-combustible. When heated to decomposition, phosgene (CG) produces toxic and corrosive fumes (hydrogen chloride, carbon monoxide, and chlorine). For small fires, use dry chemical or carbon dioxide. For large fires, use water spray, fog, or regular foam. Move containers from the fire area if it is possible to do so without risk to personnel. Do not get water inside containers. Damaged cylinders should be handled only by specialists. For fire involving tanks, fight the fire from maximum distance or use unmanned hose holders or monitor nozzles. Cool containers with flooding quantities of water until well after the fire is out. Do not direct water at the source of the leak or at safety devices; icing may occur. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tanks. Always stay away from tanks engulfed in fire. Run-off from fire control may cause pollution. If the situation allows, control and properly dispose of run-off (effluent)