IV VENTILATION 16& 



that if the percentage of carbonic acid is to be kept down 

 to the limit of -05 per cent, a man should live in a room 

 whose capacity is not less than 28,000 litres (1,000 cubic 

 feet) and into which at least 60,000 litres (2,000 cubic 

 feet) of fresh air are admitted each hour. ^ 



1 A cubical room niue feet liigh, wide aud long, contains only 729 

 cubic feet of air. 



