environmental
air
atmosphere
blue
building
business
carbon
chemical
chimney
climate
cloud
coal
contamination
danger
dioxide
dirty
ecology
emission
emissions
energy
environment
exhaust
factory
fog
fuel
fume
fumes
gas
global
industrial
industry
manufacturing
petroleum
pipe
plant
pollution
power
production
refinery
sky
smog
smoke
station
steam
technology
tower
toxic
vapor
warming
white