Explorit LA Fire Nov. 2008 -1W

Helicopters help battle a wildfire north of Los Angeles in November, 2008. Lars Anderson/Courtesy photo

Local News

Explorit: The science behind summer wildfires

By From page A7 | July 11, 2014

Summertime in California brings a lot of fun in the sun, but it also brings the possibility of wildfires.

Wildfires are any unwanted or unplanned fire that causes damage in a forest, shrub or grassy area. Occasionally, a wildfire can be started by lightning or another natural process, but nine out of 10 wildfires are caused by human activity such as a discarded cigarette or an improperly extinguished campfire.

Depending on the conditions, a wildfire can spread quickly, causing plenty of damage. Firefighters use the “fire triangle” to explain what keeps fires going. The “fire triangle” includes oxygen, heat and fuel — the three ingredients necessary for fire.

A fire needs each element of the triangle to keep burning. If firefighters can remove one element, they can get control of the fire and begin extinguishing it.

Every material has a temperature at which it will burn. That’s called its flash point. Wood’s flash point is 572°F. At that temperature, wood emits a hydrocarbon gas mixture that blends with the oxygen in the air and creates flame.

It takes heat to get wood to emit the right gases, but those gases also need the oxygen in the air. Each part of the fire triangle relies on the other two. And wood is just one possible fuel for a fire.

One way to control a fire is to control the amount of fuel it can access. When there’s nothing left to burn, a fire will have to die. You can help protect your home from wildfires by clearing a perimeter of several feet around your house free of dry vegetation. That will limit a fire’s fuel.

Heat is the element that allows a fire to spread. Heat dries out the moisture in potential fuel sources, creating a path for the fire to follow. One way to lower the temperature and help contain a fire is to spread phosphate fertilizer over the fire. That’s the reddish-orange stuff you sometimes see dropped over a wildfire from an aircraft.

Oxygen is the final part of the fire triangle. Air typically contains about 21 percent oxygen, but many wildfires need only about 16 percent oxygen to keep going. Fighting fires with smothering chemicals like carbon dioxide (an ingredient in some fire extinguishers) prevents the fire from getting oxygen and helps kill it.

According to YubaNet.com, there have been more than 27,000 fires nationwide within the past 12 months. And CalFire advises that with the drought this year, fire danger is high. But there are a few easy things you can do to help prevent wildfires.

Never discard a burning cigarette or any other smoking materials. Fully extinguish them before disposal. The same applies to barbecue coals. Never put hot coals in the trash; allow them to fully cool before discarding.

When camping, never leave a campfire unattended. Fully extinguish it with water and stir the ashes until they are cold before leaving your campsite or going to sleep. If you see an unattended campfire, call 911. Keep California fire-safe this summer!

Explorit’s coming events:

* Interested in membership? Think your Explorit membership may have lapsed? Call Explorit at 530-756-0191 to check or sign up.
* Don’t miss Explorit’s Aug. 6 field trip for fifth- through seventh-graders to the Discovery Museum’s Challenger Center. For tickets, search “Explorit” on brownpapertickets.com.
* The “Final Blast Festival and Chemistry Show” will once again wow you and your kids, on Sunday, Sept. 7. This event celebrates the end of Explorit’s summer science camp season and is a fun way to start the new school year.

— Explorit Science Center is at 3141 Fifth St. For more information, call 530-756-0191 or visit www.explorit.org, or “like” Explorit on Facebook at www.facebook.com/explorit.fb.

Lisa Justice

  • Recent Posts

  • Enter your email address to subscribe to this newspaper and receive notifications of new articles by email.

  • Special Publications »

    Use of this site constitutes acceptance of our Terms of Service (updated 4/30/2015) and Privacy Policy (updated 4/7/2015).
    Copyright (c) 2016 McNaughton Newspapers, Inc., a family-owned local media company that proudly publishes the Daily Republic, Mountain Democrat, Davis Enterprise, Village Life and other community-driven publications.