Carbon monoxide - produced in inefficient combustion
Aldehydes - produced in decomposition of animal bodies (fats, oils)
Nitrogen oxides - produced in combustion
Phosgene - produced in decomposition of chlorinated hydrocarbons
Suspended particulates - many types of operations produce solid and/or liquid particles that become suspended in air and are referred to as “particulates”. They range up to 1 millimeter in diameter.