Carbon Monoxide and cooking stoves

Carbon monoxide poisoning is the number one cause of unintentional poisoning deaths in the world.

Carbon Monoxide (CO) is produced by the incomplete combustion of fossil fuels, including wood.  Incomplete combustion results from insufficient air to fuel mixtures.  CO has no smell, taste or color and it is impossible to know when there is a dangerous build-up of CO levels( without instrumentation).

Dangerous amounts of CO can accumulate when the fuel is not burned properly as in an open fire, or when rooms are poorly ventilated. Carbon Monoxide poisons by entering the lungs and displacing oxygen from the bloodstream. Interruption of the normal supply of oxygen puts at risk the functions of the heart, brain and other vital body functions.

In the United States different municipalities have different criteria on which to base estimates of air quality, most however are governed by the Environmental Protection Agency (EPA).  Most US codes uses the term "good" to describe air with less than 9 parts per million (ppm) of carbon monoxide (CO), "fair" to describe air with between 9 and 15 ppm, and "poor" to describe air with greater than 15 ppm CO.

HELPS has measured CO concentrations of 160 ppm in homes in Guatemala where the cooking is done on open fires.  After these homes receive the HELPS stoves, CO concentrations drop to  3-5 ppm.