Tuesday, May 11, 2010

Fire Behavior

Here's a good YouTube video for illustrating fire behavior principals.
We all know that in order for a fire to burn you must have fuel, heat, and oxygen.  Solids and liquids don't burn, only gases.  As the solids and liquids heat up they decompose and release combustible gases that will burn.  At the 12second mark of the video look at what happens to the smoke.



The smoke venting from the doorway starts to light up because it was too rich to burn until it got into the atmosphere.  It's way hot (look at the push behind it and how it is flowing straight up), and obviously from the dark color we know that it is chock full of unburned material.  All it needs is that breath. 

I'm not sure when this video started in relation to crews arriving, but it seems like their is some kind of water supply issue.  The stream is weak once it starts and the pipeman was standing there waiting to open up.  This is a situation where you might want to start a little further back from the door as well.  Just a few thoughts and some things to look for.

Stay Safe

Saturday, May 8, 2010

Bread and Butter Fire Attack

Pretty decent little fire attack.


Okay, this really is a bread and butter fire attack for every fire department in the country.  One story, frame, occupied, probably 25' by 30'.  The front room is involved, but the smoke doesn't look ugly from what you can see on the video.  The nozzleman does a reasonable job of leading out, and the fire is knocked quickly.  I like the entry through the front door.  It's faster than trying to get around to the rear (did you see the fence?) and also makes sure your Engine is doing a primary of the likely escape route if there was someone inside.

They get up and open the roof fairly quickly.  To my way of thinking that is a two person roof job but I know some departments prefer to send a larger crew.  All in all a nice little video of what happens when we get water on the fire.

Think about what you would do if things were different.
Mental Rehearsal number 1: Let's say you pull up as the first Engine.  You are the experienced nozzleman  and your officer is a bit of a worrier.  As you step off the rig and take a look you go to stretch and the officer says, "Hit it from the window first."  Does that sound like a good idea?  Is this a fire that needs a defensive to offensive mode of operation to make it safe?  No.  Be ready to step up and say, "If we put the line in the window we are going to push fire into the house. We can get this one boss."

Mental Rehearsal number 2:  What would you do as the Truck if you were first on scene and there was someone standing on the front lawn saying, "The baby is in the back room!"  Are you waiting for the Engine?  Obviously not waiting for water will put you in a situation that could become untenable quickly.  Waiting for water could mean the kid dies.  I think this is one of those situations where you do some RECON and see if you can make the grab.  You have 600 square feet tops here.  Based on the smoke the door to the fireroom may be closed.  If not, you may be able to scurry down the hall with a can and get control of the door.  Even a hollow-core door will buy you a few minutes to do a primary back towards the front of the house.

My only "do better" on this video is that I hate to see people getting off the rig with their SCBA Facepiece on.  I know MSA has the ability to let you breathe ambient air,  but the mask limits your peripherial vision and makes it much harder to take in the big picture.  Look at the guy running up to the door with the axe.  Running on the fireground should only be away from the building, otherwise you are moving forward faster than you can visually process.  Take the second to don your mask prior to making entry, that way you can slow down and "pull your boots up" the way generations of folks did.  It gives you that second to get a sense of the whole scene and prepare for the job.

Again, just my two cents.  Cheers!

Thursday, May 6, 2010

Training Video Time, Kids!

Watch what happens at roughly the :45sec mark.


This is why we don't vent behind the Engine!  By the 1:18 mark you can see that there was an Engine Company inside making what was probably a very difficult push to the seat of the fire.  Even with the failed window in the fire room there was still a tremendous amount of heat in the front.  Read the smoke!  It's pushing out under pressure from the front of the building.  This is one of those times we have to open the roof!

Most departments out there are operating at a deficit when it comes to responding manpower.  There aren't enough people to go around.  Regardless we have to figure out a deployment that allows us to open the building up properly.  You'll see once they are outside and choose a defensive attack (any attack made from outside the building is defensive) it takes roughly :10sec of water to get a knock on the fire room that was causing the problem.

Once one interior room has flashed over the rate of heat transfer to the rest of the house skyrockets.  Think of it like your oven.  Until the thing heats up you can set potatoes in there bare handed all day long.  Once it is 400 degrees though it gets warm just standing in front of the open door.  The interior of the fire building is the same way, just that room that flashed is radiating 1500 degrees or more into the rest of the house.

Back to the embed video.  About the 4:00 mark you see two guys head to the roof and then hear the saw running.  We can see that the D side still has a well seated fire.  At 5:02 we see a member venting the front gable window of the 1/2 story (which is probably occupied living space).  There is probably the same window in the rear.  These windows aren't the best for "vertical" ventilation, but they do pop the cap and start to relieve some of the pressure.  They may be better than not having any kind of top side opening.  The primary concern has to be not dragging the fire into unburned areas where victims may still be.  However given the level of fire development there is little chance that without venting those windows anyone on the second floor would live long.  We have to control the environment!

As you continue to watch the video there are some questionable choices made.  Why?  Lack of Situational Awareness!  Do we perceive, comprehend and predict what is going on? This is one of those videos to sit down and have a shift drill with.  Talk about what is going on and then how you would handle the fire if it was in your town.

As always it is easy to Monday morning quarterback someone's fire and pick out things that could have gone differently.  However only by looking at these things do we have the opportunity to learn from the experiences of others.  How many fires have you been to this month, or even this year?  These videos, and hopefully my blog, are the mental rehearsal opportunities I keep talking about.  Make the most of every fire you can watch and review.  It's no different that a professional athlete watching game video!  Make the most of every fire you see.

Just some thoughts and a good video. Cheers and be safe.











Wednesday, May 5, 2010

The 360


Who does the 360° Size-Up on your department? I have heard answers ranging from "The First Due Officer" to "The Incident Commander" when I've asked it in classes. I am a big believer that getting someone around to the "REAR" is critical. You have to get as complete of a picture as possible, and we don't pull up on scene with a Google™ Earth view on the scene with built in thermal imaging. However, the situation really dictates who is going to get a view of the rear.

Let's look at the image below.



























Hospital Complex

If you arrive on scene of a reported structure fire in this building is the first in officer going to take a lap of the building? The brothers and sisters will have a line on the fire and the poor officer is going to have a heart attack trying to take a lap.

I'm of the opinion that the job of the first due Engine Officer is to get as good of a picture as possible from the front of the building (three sides since you left room for the Truck right?) and then get inside and start worrying about the internal exposure problems if you are going to choose an Offensive attack.

Even on a smaller occupancy like an apartment building three sides may be all you get.












U-Shaped Apartment Building


 

If you are looking at a "normal" (say 1000 square feet per floor) single or two-flat type occupancy then the Incident Commander can get a good view of the back. Take a look at the house immediately north of the house with the pool in the center of the photo.

Here's one where the IC can take a lap. 

I hear the question now, "The initial Incident Commander, Chris?" My answer is "Not if you are going into a rapid offensive operation and the initial IC is the first in Engine Officer". If the Officer of the 1st Truck/2nd Engine will be outside then by all means he or she should take a lap, if it's reasonable. There are times like our examples above where the IC cannot get around to the rear.




Consider the facts surrounding the Huston Fire Department's April 12, 2009 double LODD. The rear of the structure was inaccessible because of Chain-Link fencing that delayed anyone making a "quick" check of conditions in the rear. This isn't an uncommon situation. Is the IC going to delay operations because he or she can't get a lap? NO! If we are going to operate in an Offensive Mode we need to be aggressive. Think about fire growth. The NIST "Flashover" video shows that from ignition of a sofa in a normally furnished living room it takes 3 minutes and 19 seconds for the room to flash. As soon as the first room flashes we have a heavy heat condition pushing through the building that is going to accelerate the decomposition of the building and its furnishings. If we are going to commit to the inside of the building we must do it aggressively.

So, who get's the rear on the complicated structures, or the ones where you need to get over the fence or distract a pack of dogs?


Whoever is assigned the role of Outside Vent must get around to the back side of the building. This member should be taking a 24' Extension Ladder, a Halligan, and a 6' or 8' Pole. This gives a set of eyes in the back of the building right away. It get's a member in the rear who can throw a ladder for secondary egress or for rescues, and perform some ventilation. It gives the Engine Company the comfort of knowing that someone is communicating the conditions in the rear and gives some quick horizontal venting for the fire room (ideally) or at minimum opposite the Engine Company. Any doors on the ground level should be forced and the OVM can make a sweep with a tool to make sure there are no victims trying to escape. What if you don't have a Truck? Someone still needs to be given the assignment of being the OVM. Ventilation opposite of the Engine is critical. Far too often the well meaning but stupid will rush up and vent the front picture window as the Engine is getting a good push down the hallway. This should be obvious but opening up a picture window gives you 10 to 12 square feet of ventilation. All that is going to do is pull fire onto the Engine.

I hope you all find use in these thoughts and ideas for you to toss around the kitchen table. For an awesome overview of the job of the OVM check out Nate DeMarse's (FDNY) article in Urban Firefighter Magazine.