mass of airborne particulates and gases

Smoke is a cloud of very small, solid particles that is made when something is burned with a flame, such as wood or paper.

Smoke can be bad because if it goes into the lungs of a person, it can hurt their lungs or even kill them (for example, in a house fire). Most people think that they are always able to see smoke, but people cannot see some types of smoke: they are invisible.

Smoke removal systems redistribute gas flows and reduce the temperature and concentration of smoke during a fire. This helps in evacuating people, limiting the spread of fire; and extinguishing the fire.[1]

Smoke from tobacco


When people smoke tobacco in cigars or cigarettes, they are burning the tobacco and inhaling the smoke. Tobacco smoke can hurt the mouth, throat, and lungs. It can cause mouth, throat, or lung cancer. It can also cause emphysema and bronchitis (trouble breathing). They continue doing it because the smoke also has a nicotine.

Smoke from factories


Factories and power plants produce large amounts of smoke into the atmosphere which pollutes the air. Eventually the toxic chemicals in smoke fall to the ground, and then they pollute the soil and the water. When the air, soil and water are polluted with toxic chemicals, the chemicals also get absorbed by plants and animals (including humans).



  1. "Highrise building smoke removal" (PDF). Sacramento Fire Department.