air
blue
chemical
chimney
construction
dioxide
dioxin
distill
distillation
distillery
energy
engineering
environment
environmental
factory
fossil
fuel
gas
gasoline
global
greenhouse
industrial
industry
kyoto
metal
oil
petrochemical
petrol
petroleum
pipe
pipes
plant
pollute
pollution
power
production
refine
refinery
sky
smoke
smokestack
steam
steel
tank
technology
tower
toxic
warming
working