air
bituminous
black
blue
calorific
central
city
cleaning
coal
constructor
crock
dust
effect
emission
engineer
environment
environmental
factory
filter
fume
gas
green
greenhouse
heat
house
illness
industry
lung
mask
ozone
plant
pollution
power
respirator
respire
sickness
sky
smoke
soot
stack
station
steam
technology
thermal
warming
warmth
water
white