Three Lessons from the Fire Behavior Lab

Today’s firefighters are experiencing an old danger that has come full circle to affect everyone.  Flashovers are becoming a more common problem due to many factors.  Why are we seeing more and more of them when we arrive?  I believe that it is due...

This is a huge lesson that you can learn from the fire behavior lab.  As you instruct your students on fire behavior, you can learn that fire will “Reach” or “Finger” out of the room of origin looking to extend over your head.  This sometimes can be seen, but sometimes it cannot.  You need to be watching the smoke as it passes over your head for velocity and smoothness.  Just because there is a fire on the B-C side and none visible on the D-A side, there still is a danger present.  The fire is looking to make its way toward the unburned side.  If your attention remains fixed on the self venting fire, you can make some big mistakes in dealing with, or missing, the signs of danger.


Turbulent Smoke Has Fire in It

A lot has been made of reading the smoke to which you are responding while there is hardly any talk about what the smoke looks like that you are crawling under.  Thick black smoke that has a “waving” look to it may have fire hidden in it. We can gather a lot of information about the fire by looking at the smoke and its movement along the ceiling.  Is there fire above us? Should we cool the ceiling with some short blasts of water? These are two questions you should be asking.  By hitting the ceiling with short blast of opening and closing the nozzle, you can reduce the chances of flashover. Fire burning above your head can lead to a disaster, so knowing the signs that it may be present are key learning lessons taught in the fire behavior lab. 

While inside the lab, you should be paying attention to the smoke as it begins to build up and push to the floor.  The fire will build inside the burn room, filling it with fire before extending into the long hallway of the chamber.  The first signs will be small fingers of fire as it searches for air.  Flames licking out slowly may or may not be seen.  Once the fingers progress, you will reach rollover.  If you are experiencing a rollover during a fire, you should knock it down and not let it reach any contents behind you as it will trap you. 



Flashover is a danger that should be on the forefront of your thinking when you receive notification that you have a fire.  Keeping in mind the time it takes to discover, report and respond when you arrive that a flashover may be just about to happen. Key points that can be learned inside a flashover simulator, can teach all firefighters what to watch for and how to combat this growing trend.  Use the fire behavior lab to challenge your students to know when it’s time to get out.  In review, firefighters must understand that if you don’t wear your proper PPE, you will get burned.  If the smoke above your head is turbulent, suspect that it has fire in it.  Most importantly, don’t get tunnel vision and focus all your attention on the part of the structure that is burning.  The fire will grow, the smoke is flammable, and given the right mixture, it will flashover.  If you have the ability to take your firefighters into a flashover simulator use it for its intended purpose, to educate them on when it’s time to get out. 

Stay safe everyone!

RYAN PENNINGTON, a Contributing Editor, is a firefighter/paramedic for the Charleston, WV, Fire Department. He is currently assigned to Station 8 and a member of the West Virginia Task Force 1 USAR team. He has over 18 years of combined fire, rescue and EMS experience. Ryan is currently a West Virginia State Instructor 2, Hazmat Technician, and Certified Fire Officer 2. He is the author of the "Views From the Jumpseat" blog on You can reach Ryan by e-mail at: