air
air pollution
architecture
blue
built structure
chimney
clean
clear sky
closeup
cloud
color image
condensation
contemporary
day
directly below
environment
factory
fumes
gray
high up
industry
industry chimney
new
nobody
old
outdoors
pipe
pollution
red
row
simplicity
single object
sky
smog
smoke
smoke stack
sparse
steam
sunlight
tall
tube
unhygienic
vertical
white