air
building
business
carbon
chemical
chimney
city
color
construction
distillery
ecology
emission
energy
environment
environmental
equipment
evening
exhaust
factory
foundry
fuel
fumy
gas
generate
global
industrial
industry
maintenance
metal
night
oil
pipe
plant
pollution
polution
power
production
scene
silhouette
sky
smog
smoke
smokestack
stack
station
steam
sunset
technology
tower
warming