your health. Why air must be kept moving

302 YOUR HEALTH Why Air must be kept moving Stuffiness is due to still, warm, moist air. A healthy body gives off heat and moisture all the time. If in a closed room the air is not moving it becomes hotter and hotter, moister and moister, until you feel uncomfortable. This is stuffiness. Stuffiness leads to fainting, and in its extreme form, to heat-stroke. Ventilation does two things: It keeps the air on the move. It replaces warm, moist, stale air with cool, dry, fresh air. Fresh air from outside contains fewer germs than inside air.