environmental
air
air pollution
atmosphere
branch
chemical
chimney
climate
climate change
co2
construction
contamination
danger
dioxide
ecological
ecology
energy
engineering
exhaust
factory
fog
fume
global warming
industrial
industry
manufacture
manufacturing
outdoors
petrochemical
pipe
pollute
pollution
power plant
power station
production
refinery
safety
sky
smoke
smokestack
station
steam
steaming
tower
tree
tree branch