, 4 min, 737 words
Tags: emergency-response mount-erie-fire fire-stuff
In Anacortes, I have the unique privilege of volunteering with the local Mount Erie Fire Department, or Skagit County District 11. I joined just in time to get in on this year's red card training for wildland firefighting. I learned a ton, met people from across the state, and ended up earning my red card (or incident qualification card, if you want to be all modern about it).
To understand wildland fires and how we act to suppress them, we need to briefly go over the "fire triangle." The fire triangle states that fire needs three ingredients to thrive: oxygen from the air, fuel to burn, and heat to allow burning. In order to suppress a fire, then, we need to take away one or more of those ingredients.
Caveat: I know nothing about structural fires or how to fight them; all of this is rephrasing what my instructors told me about comparing wildland and structure fires.
In structural firefighting, we suppress a fire by dumping a lot of water on it. This acts to cool the fire and also gets in the way of the fire's oxygen supply, attacking the fire from two angles. In comparison, in wildland firefighting, water is often in short supply. We rarely have fire hydrants where they'd be useful, and the sheer size of wildland fires would make water use prohibitive. Instead, we take a different approach: remove the fuel the fire will use, and eventually it will burn itself out. To do this, we create fire line around the entire fire. That line can be dug by humans or large equipment, and it has to be wide enough to reasonably expect to stop the fire given current and forecast conditions.
If you've followed news of wildland fires in recent years, you'll have heard the term "some percent contained." If you're like me, you probably thought that 100% containment meant we were finished fighting the fire! Alas, the job is far from done. Containment is a simple mathematical way of describing how much fire line is complete. If the perimeter of your fire is 100 feet, and you've dug line along 20 of those feet, you're at 20% containment. That is, as long as you can reasonably expect the line you've created to hold. Thus, 100% containment means only that you've built line all the way around the fire. It's an important first step! But there's still work to do.
Controlling a fire is the next step. In fire control, you reinforce your line, widen it where needed, and suppress hot spots that could pose a risk of jumping the line. Once your fire is 100% controlled, you can reasonably state that everything outside the line is safe from further spread of the fire.
One thing to note here: I never realized how dangerous it can be to have unburned fuel between your line and the fire. In order to avoid these situations, we either build line right up against the fire (a direct attack) or "burn out" the area between our line and the main fire. This is termed "bringing the black with you," as you ensure that "the black" (the burned-out area) comes right up to your line. It also effectively widens the buffer zone between the fire and the rest of the world, making your work more effective.
Once a fire is controlled, it's not necessarily done burning; it's just not going to get out of its cage. A fire isn't considered out until there's been no evidence of fire activity for 48 consecutive hours. That often necessitates the dirty work of mopup: hours and days and weeks of painstaking foot by foot progress through the burned area ensuring all remnants of the fire are out.
All in all, I had a lovely two weekends of learning about and fighting fire with some amazing people. Thanks to Chief Mike, lead instructor Jordan, all the fabulous instructors, and especially go my squadmates on squad one! I learned a ton. From all of you. Here's hoping for a relatively light wildland season this year!