From Fuels to Smoke: Chemical Processes

Combustion is a chemical process that results in the oxidation and breakdown of organic matter from living and dead vegetation. The products emitted during complete or incomplete combustion include gases such as carbon dioxide, water, and nitrogen, as well as carbon and minerals. Particles of organic matter that are only partially consumed are left after most fires, and they are often part of the smoke that can spread to areas far from the flames. The particulates and other compounds in smoke can affect visibility and pose health hazards to people. In this second chapter of our book, Fire science from chemistry to landscape management, we present fundamental concepts related to the factors influencing combustion products, including the emissions of particulates and gases. The interactive spreadsheet reinforces understanding as users can visualize how altering the oxygen supply and chemical composition and moisture of the wildland fuels will alter smoke chemistry and particulate emissions from vegetation fires, whether those are prescribed fires or wildfires.