MODULE 1 Health and Environmental Effects of Smoke

Smoke in the "Breathable Zone"

Smoke does not always travel up and away, dispersing as it goes.  Frequently in the evening and morning in mountain valleys and low-lying areas, temperature inversions can trap smoke near the ground.  Inversions occur when air near the ground is cooler than the air above, preventing the upward movement of smoke.  The lid effect of inversions, coupled with a drop in wind speed,  causes smoke and pollutant accumulation in the “breathable zone” near the ground.  Smoke near the ground can also reduce visibility on roadways increasing safety hazards and has caused severe vehicular accidents.