The Chemistry of Fire

Fire is captivating, entrancing, primal and powerful — dangerous yet graceful and calming. It’s a mysterious, hypnotic force that inspires stories of Prometheus stealing it from the gods, as well as many idioms and expressions, like I have fire in my soul or Those shoes are on fire!

When you light a campfire or cozy up by the hearth, there’s nothing more relaxing than listening to the flames dance and the occasional snap, crackle, pop. In fact, studies show that it can lower your blood pressure and even promote pro-social behaviors!

The basic chemistry of fire is that it’s an exothermic process (it produces more energy than it consumes). Chemical bonds break down, and new bonds form. The energy released is the heat of combustion, and this release creates the dazzling display of light and movement we know as fire.

In the case of a house fire, you can minimize your exposure to smoke and ash by closing your doors and windows, putting out candles and turning off all appliances that produce heat or generate a lot of electrical current, including air conditioners. It’s also a good idea to have an evacuation plan on hand and practice it regularly, so you will be prepared in the event of an emergency.

If you are planning on a controlled outdoor fire, choose a clear, level area away from overhanging branches and vegetation. Scrape the ground down to mineral soil or non-combustible material and dig a pit for your fire ring, if possible. If not, scoop a pit and fill it with the tinder of your choice (twigs, grass, leaves, small sticks).

Once your fuel has been ignited, add larger pieces of wood until you have a pile about ten feet in diameter. Adding more tinder and continuing to add larger pieces of wood will keep your fire going until you’re ready for marshmallows!

Class A: Ordinary combustible materials, such as wood, cloth, paper and many plastics. Burns with a bright red glow and leaves an ash. These types of fires can be extinguished by cooling the fuel to a temperature below its ignition point or using dry sand or powdered, non-combustible salts.

Fires caused by faulty electrical appliances or malfunctioning cooking equipment are more difficult to extinguish. These can often be prevented by performing a thorough electrical inspection of your home once a year and having all appliances checked by a professional every five years. It is also important to properly store flammable materials, and have working smoke detectors.

It’s not just houses that need to be ready for a fire – wildfires are becoming more common in the US, as we have become increasingly urbanized and drought-prone. Wildfires play a valuable role in ecosystem health, clearing underbrush and enriching the soil with nutrients by removing old growth that is unproductive. In addition, they can help reduce the impact of invasive species that can overtake native plants and change the carrying capacity of our forests.