1.   In his day it was factory smoke, not petrol,

2.   And the villain this time around is not factory smoke stacks belching pollutants into the air.

3.   The sky was dark as factory smoke, and even darker to the north and west, out of which the storm was howling.

4.   They belch factory smoke.

5.   Freezing winds send snow squalls and factory smoke drifting across the endless tundra of this bleak mining outpost.