This Crash Course On Wildfire Thermodynamics Can Save Your Life
To better follow this post, have a read at “4” Ways Mother Natures Comes In Hot.
A Likely Wildfire Scenario
Imagine you are driving your car through the woods and notice something isn’t right. Light smoke, getting denser and denser. There are flames starting to get closer and closer to the road. Wind is mild.
Now lets understand how and why the 3 types of heat we’ve gone through before can be pretty dangerous to you and what you can do to run to safety…
Conduction Heat Trajectories
A wildfire scenario has less heat conduction trajectory then a domestic fire, because, objects are normally farther away. In a wildfire you should be aware of conduction heat in two ways, (1) the road tarmac; (2) hot surface in your car. Both of these are caused from absorbing radiation heat emitted from fire cores.
This is why you should always carry appropriate shoes (closed and & high soles) and, if possible aramid gloves, when driving through the woods or forest. The most appropriate gear we can recommend here are the Faraday Boots and Faraday Gloves from your Kit. The Faraday Boots are in a special kit. But, at the end of the day, just make sure you have some protection regardless of who sells it to you.
Convection Heat Trajectories
This one is the trickiest of them all. There are two main trajectories for Convection Heat to find it’s way to you in a wildfire. (1) Wind Forced Convection; (2) Wood Combustion Gases (short-range).
Hot air convection currents actually play in our favor in case of a fire. Since hot air tends to naturally rise in the skies, it also means, that the air that has been heated by the combustion don’t just stay there like in a closed oven. No. It convects upwards.
Problem is, when the wind is very strong and, overshadows the natural upward convection of hot air. In this case, More hot air can be moved towards you then otherwise. This one is very dangerous.
The convection currents that arise from Wood Combustion are normally kept within a few meters. When wood burns, some of the by-products are hot gas gushing out, e.g., flames. BTW, a flame is just very hot gas, emitting light on the visible range.
This type of convection can be avoid if you can avoid going through fire cores.
Safety Tips, if you have to jump out of the car a run to safety with hot air convection currents coming at you, crouch or crawl as much as you can because the temperature is lowest closest to the ground. Also, avoid as much jumping going to areas where ticker trees are burning, because they ll for sure have more hot gas gusts.
Radiant Heat Trajectories
Remember what we talked above regarding everyone emitting radiant heat? Well, guess what, fires do to, a lot. And, it is the form of heat most likely to get you first in a wildfire.
The higher the core of a fire, the stronger the radiant heat flowing from it. Radiant heat propagates through electromagnetic energy - light - carrying a lot of energy. For you to have an idea, a fire core burning with a temperature of 1250C, will have at 5 meters distance, a radiant heat translated into a 500-600C! That will burn everything organic in seconds.
The good news are, since radiant heat is actually light, it can be reflected to a certain level. The Faraday Blanket does exactly that, reflect killer radiant heat away from your skin. This effect of shielding an object from an electromagnetic field can be called Faraday Caging. You probably already heard of it from the planes.
(Now you know why we called it the Faraday Kit…)
The safety hints here are, if radiant heat start becoming really unbearable, stop your car, snatch out the Faraday Blanket from underneath your car seat and roll around it. Get out of the car and, with your center of gravity as low as possible, try to run for safety. Remember your blanket is reflecting 95% of incoming radiant heat, but the 5% will start rising the blanket temperature. If it starts getting to hot, loose it a little from your body, always keeping every inch of your skin covered.
Hope you never need to use this…