Examining Fire Fighting Tactics under Wind-Driven Conditions (Pt. 4)

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And I love these guys; I got to tell you how
much I love these guys, because they get it. Do you think these
engineers need that video to understand
what’s going on? Truth is they don’t. That’s for us, right, they are doing that
for us, they get it, they understand what
it is we need to see, they understand
how to package it, and couple it with the
engineer stuff, right? So we can build
up, we can take it, we can and it
gets even better, Steve is going to
make it even better. Thanks Pete. I have a great privilege to back
cleanup for these gentlemen and they battled
through a lot of it and we are going to bring
it down to the realistic, take it out
into the field, and take it to the street
level firefighter, give them a chance to
see what’s going on and that’s what really
drove this next set, was you can sit out here, you can see the
little experiments we did in the lab and it
peeks your interests, get you thinking about it. But again, like Dan said, you don’t fight fires
in the laboratory and that’s what took us
to Governors Island. We are not to be outdone, the
Fire Department in New York after we got buildings
with Toledo in Chicago. They got us an island and we got a seven story
building on this island to essentially turn
into a laboratory. And what we wanted to do
in our laboratory is we want to expand on what
we had seen previously. We wanted to take
the PPV experiments that we had done in
Toledo in Chicago, want to expand them to
make another data point, how do they work in
a 7-story building. We did it in a
30-story building, we did it in a
16-story building, let’s try it in a
7-story building. Let’s look at
pressurizing stairwells, lets’ look at maintaining
conditions in the stairwell for the occupants
do egress and the Fire Department to
set up their operations in a more tenable atmosphere, what can we do
in this building and how do those fans work
against wind driven conditions, what tactically
needs to be done in order to use that
successfully and/or can things happen where that’s not
the tactic to use. We looked at Wind
Control Devices again, both the blankets
and the curtains to get an idea of how
this works vertically. We start lighting
fires in the 7th, 5th and 3rd floor, what
kind of conditions do we see, and then alternative
strategies of attacks. So the floor below
nozzles introducing water flanking it from
in a safe location, looking at different
streams; fog streams, smooth bore streams, how
do these different things impact conditions
in the corridor where the Fire Department
would be advancing sort of as a Plan A. Let’s start validating
these tactics for Plan B. Plan B should not be to
send Engine Company after Engine Company down
that hallway burning them up, until the fire goes away and they can walk
in and put it out. We need a Plan B. Here is our island. You can see our 7-story,
as Jerry you will say your fireproof
multiple dwelling and we turned this
into a laboratory. Right there in
New York Harbor, right off the tip of Manhattan
to give you some orientation, the closest point on land to the face of the
Statue of Liberty and got the opportunity to turn that into
a laboratory. Here is the Floor Plan. Two identical sides
of the building, we burned run up being
14 experiments in 12 different apartments,
on the 7th floor, the 5th floor and the 3rd
floor starting at the top and working down, looking
at these different tactics. We ran miles and
miles of cable to measure temperature
in the fired apartments, temperature in the
corridors, gas velocities, how quickly are
these air currents moving through this building. If you open
different doors, if you open
your bulk head, or you open the
base of the stair, what does that do to the
flows in the structure? When might you want to
open the bulk head, when might you not, try and answer all
these questions. We got all of the upper
echelon of the New York City and Chicago Fire Departments to start putting together
what if scenarios. If you were to implement
these tactics, what would you want to
know ahead of time, as opposed to trying it
for the first time on the fire scene? It’s not the time you want to
be experimenting with things. So we implemented all
of their questions, all of their suggestions
into these 14 experiments to start answering some
of these questions and we are going to go through
some of them tonight. The bottom line is you’ve
got a 600 Page document and 100 of hours of video
to answer those questions and that’s something that
we are going to pile through. Here are a couple
of shots real quick to give you an overview
of what we did. We wanted to
simulate the wind and one of the reasons this building in
particular was interesting was that probably 360
days out of the year it’s subjected to wind, so we would have
an opportunity to run some experiments
with some natural wind, as opposed to having
to make the wind like we did in
the laboratory. Well, more than half
of days we were there, there was no wind, so
we had to improvise and we used the mobile
ventilation unit that you see in that the two
pictures on the side there. That gave us an opportunity to make a known velocity
going through that window, we knew what the wind was and we were measuring
it continuously and we actually got a few
natural wind conditions as well and we will look at
a couple videos of them. You can see the furnishings
of the apartments. We used similar furnishings that we used in the laboratory so we can start connecting
the points here, understanding what
the energy release is in the structure
and moving from that, so you can see a
furnished living room and a furnished
bedroom there, all of these apartments
were furnished throughout and were done
repeatedly 14 times. Here’s a quick video
showing an outside view where our fire was in the
bedroom right here and we are looking from the
bedroom our simulated wind blowing in through
the bedroom, down into the living room, so you can see the flames starting to blow through
the living room, starting to involve
the living room. The public hallway where you got flames just
rolling down the corridor, and then you have got the
stairwell door open and the bulkhead
door open as well and you’ve got flames
all the way from the bedroom more than
150 feet away coming into the stairwell with absolutely no fuel with
the exception of paint and concrete in between
the living room and the stairwell door. And you’ll see here, the
living room window fails. Very important, I want
to size-up to see all sides of the building, just because you
have no flames or you have got flames
pulsing out of the B side, and you have got flames
venting extremely quickly out of the A side,
doesn’t mean that you’ve got a naturally
ventilated fire and there’s no wind conditions and everything is okay. It’s important to see all
sides of the building and the other important
thing was even when that living room window failed, sort of creating the
path least resistance, sort of a 6’x8′ opening in
the side of the building, there was still enough flow to completely split
going out that window and still producing flames
through the hallway into the stairwell. So you’re talking a
serious amount of air moving through
this building that you don’t want to
be in the way of. First thing we looked at,
positive pressure fans, we know they… we know
we had the ability to use them successfully
to protect stairwells in a non-wind driven condition, how do they work in a
wind-driven condition and we looked at a
number of scenarios. The fans we used here
27-inch portable fans, similar fans that we used in
all of our other experiments, sort of the largest
portable fan that you can wheel
around and use, use somewhat easily and
the important thing there is to purchase fans
for your application. If you are going to pressurize
high-rise stairwells, you don’t want to do it with
a 16 inch electric fan, it’s just not the right
tool for the job. And if you watch that DVD, you will understand
that stuff a lot more. Here is an 8-view video, looking at one of
the experiments and this fire started
in the living room. The living room is
well-involved and right now we are
pressurizing that stairwell with a single fan at the
base of the stairwell and you’ll see we are
going to turn that fan off and we go from a completely
protected stair to within seconds that
smoke is coming back down the stairwell creating conditions
that are not suitable or that you wouldn’t prefer
just sort of showing the ability to
pressurize the stairwell. When it comes to wind
driven conditions, the fans were effective at holding the flow
around the door, sort of like you saw in the
IR view in the stairwell, but as soon as you
open that door, that’s too much flow coming
in against that fan, but the fan slowed it down and created better conditions with lower temperatures
in the stairwell; very important to
utilize that tool. Here is a graph
looking at temperature. So you’ve got your
temperature in Fahrenheit on the right-hand
side here and this is an idea of the scale
of one of these experiments and sort of in the lab
we could really control, fire grows, open a vent, what was the impact
of that vent or drop a curtain, what was the impact
of the curtain? Here we’ve got seven
floors to work with and we wanted to replicate
what the firefighters would do as they arrive. So everything from opening
in the base of the stair to access the
attack stair, opening the fire floor,
opening the bulkhead, turning fans on,
turning fans off, all of these things, we
wanted to get a look at, but here we are highlighting
the use of the fans. So here you can see as
the fan is activated, what it does to
the temperatures, mainly in the
stairwell is what we are looking at
on the bottom here and it drops temperatures
up in the 200°F back down to ambient very quickly and what you saw
on the video was what happens when you
turn the fan off, that was protecting
a stairwell that had ambient
conditions, you turn the fan off and
you’re allowing that flow back in the stairwell and
you’re in the 300 to 4000F within seconds of
turning that fan off. So utilizing the fans to
protect your stairwells is an absolutely significant
tool when implemented properly. Wind Control Devices,
here is a closer look at the two Wind Control
Devices that we utilized. You have got… what
we’ll call a blanket, implemented here over
the double-window, usually requires two
firefighters on the roof and a firefighter or
two on the floor below to hold the straps
on the corner and essentially drop that
blanket over the window, shutting off the wind and that stows sort of getting
folded up in a small package. Then you’ve got the wind
control curtain here which has ribs in it,
some metal rods in it, which allow it to stiff
across the window opening and this can be deployed from a
single firefighter from above and anchored from a
single firefighter below with the corner
straps and that rolls up. This is 6’x8′;
this is 10’x12′. So you can see the
scale of the two Wind Control Devices there. I’ll show you a video here of a wind control
curtain being deployed. We have got a
wind-driven condition going through this bedroom, out in the public hallway; it’s going to vent the
living room window, so you can see the flames
coming significant way out the window. You cut that air off, you
cut that oxygen supply off and as they get
it in place, that’s deploying it. It’s almost like somebody
has put motor on the fire. You cut the air off,
you kill the fire, pretty much knocks
whatever fire was in that
living room down. You remove the
wind-driven condition and pretty much go
back to the room and contents fire
that you started with before the
air was introduced. And that’s a pretty good
example right there of how that device is deployed. In this case, it was
deployed off the roof. It could easily be deployed
out of the 6th floor, over the 5th floor
or out of the 40th floor on to the 39th floor as a
tool to cut the wind off. Here is what that looks
like in engineer Es. So you’ve got our
temperatures here and we are in excess of
1500° in the bedroom, so in the top we are
looking at the bedroom. As we get down here,
we are looking at the corridor temperatures
where the Fire Department will be making their
way down the hallway. Here we are looking at
stairwell temperatures, and pretty much before that
Wind Control Device is dropped, you are in excess of
1500° in the bedroom, you are in excess of over
1000° in the corridor, completely untenable and you are up above
600° in the stairwell, also untenable
for firefighters. You drop that Wind
Control Device cutting the air supply off, essentially you cut the
temperature in half if not more and removing that
wind-driven condition, again allows you the
ability to go ahead and implement your direct
attack down the corridor. Floor below nozzles,
here’s something that we couldn’t really
extensively get a look at in the laboratory because we really didn’t
have a floor below. We looked at sort of
laying in front of a window and shooting
the water in. Here we had the ability
to essentially take tools that were in the minds
of firefighters and weld together
in their spare time and made on their own and get an idea of what
these things could do, how we can implement these
floor below nozzles and what impact
they can have. And you can see two
different kinds here. You have got the one that
comes up from the floor below, out the window and
hooks on to the window sill on the floor above
and then you can see that it essentially has
a 60° bend in it, stick straight out the window
on the floor below, bends and as you adjusted out the
window to the correct distance, you get that angle
and the water will direct itself right
into the floor above, sort of the Plan B. We can’t make
the fire floor, what happens if we
introduce water to the seat of the fire and that’s what our
experiments looked at and we also looked at the impact of a narrow
fog, a smooth bore, other fog nozzles, different
sprinkler type devices to see what
will work best, would have the
most impact. Here’s a quick video showing
another wind-driven fire. What’s important is what’s
going on in the public hallway, what’s going on
where the firefighters are trying to attack
this fire from. You see the floor below nozzles
stuck out the window here and once we get to
the right point they are going to
charge that line, they are going to
adjust the nozzle, so they no longer have
water coming back down, all the water is going
into the floor above, no firefighter has to hang out
the window on whatever floor and you see the second that
water goes in that window, wind-driven
condition goes away. You knock out those gases like
we saw in the laboratory, get some water on the
seat of the fire, your problem
starts to go away and this is the ability to put water on the seat
of the fire remotely. One of the beauties of
this nozzle right here is that that can quickly be
deployed from the floor below just like you would
stretch a stand pipeline and you can direct that
water into the bedroom and if the fire is going
in the living room or conditions aren’t
getting better, you can easily move that, right out of the side window, go out, put water
in the living room, very quick, get
a knock on it, get your crews
up to mop up. Here is with that
looks like in data. Again, temperatures
in the corridor which is what’s really important
in the excess of 1200°, flash over conditions in
your public hallways. You can’t advance on that. Stairwell temperatures
up in the 1000° range, something that you
can advance on; second that floor below nozzle
is the seat of the fire, drops the temperatures
pretty much from as high
as 1000° down, less than 300°
Celsius in seconds, validates the
tactic very well and this was done a
number of times, I am just showing
you one example. We talked about
the natural wind. One of our
concerns was that we were over
simulating the wind. Here’s a natural wind,
blowing into a bedroom fire and to talk
about pulsing, here’s a prime
example right here. If you pull up and you are
the Incident Commander, or you’re the first
arriving Engine Company and you are assessing the
conditions you have inside and you see pulsing fireballs
coming out of the window and going to the ground, you need to consider
your wind condition. This is a great example of
something you might see on a size-up and
as it turns out, what we were doing
in this experiment, was taking the
natural wind, allowing it to go through
an apartment on this wing through the corridor, and out on the apartment
on the other wing and it got to a point where conditions
deteriorated so quickly, we essentially had to
evacuate all the crews that could deploy the
blankets from the floor above, because almost the
entire floor was about to flash over simultaneously
from one end, 400 feet away at the other
end to the floor and conditions
were extremely bad and this is what they look
like out that window, and turned out that the simulated wind
was right on par. if not underestimating the
ability of the natural wind. So this sums it all up. Wind is part of size-up,
this is an important one. If you don’t realize there is a
wind condition on your arrival or make that as part of
a continuous size-up of the crews as they
are operating, sometimes you might have
no wind on the first floor and have a significant
wind on the 30th floor. That’s not uncommon, that’s something we’ve
seen fairly frequently. The ability of the people
operating on those upper floors to give that return that
they’ve got a wind condition on the floor above the fire
to make everyone aware, to start checking
their doors, paying attention
to the flows that are coming
out on the doors, to understand the ability
of that window to fail and conditions deteriorating quicker than
you can react, extremely important. Controlling doors
in the flow path, every door that you
open and leave open, is contributing
to fire behavior in that building continuously. You open the base of the stair
and chalk that door open, you just change the airflow
dynamics in that building. You open the bulkhead
door, you leave that open, you change the way that fire
is going to grow and react. One of the biggest conclusions
that’s going to come out of this is the impact
of vertical ventilation in the stair shafts with fires
that may be five floors remote and on the opposite
side of the building of where that stair
shaft is open. You want to get a fire to
grow and to flash over, open the bulkhead door,
open the stairwell and allow it to
vent vertically. That will allow that
fire to progress much quicker than if you
left that door shut. Positive pressure fans,
improve stairwell conditions in every
single orientation. Fireproof building, we are not talking
positive pressure attack, we are talking about
pressurizing space to control where
smoke can flow to, or slow down where that
smoke is going to go to. It’s always a good idea or
the common thought process is we are going to have
an attack stairwell, we are going to have a
ventilation stairwell and no occupants are going
to enter these stairwells or will be able to keep
all the doors shut and no smoke will get
into the stairwell, we’ll get all the occupants
down, no problem. If anybody really gets
that to work effectively and can keep the smoke
from leaking around the doors into the stair shafts, that might be a
viable option. Most of the time
that doesn’t happen, using technologies such as
pressurizing stairwells, which get used daily and buildings are engineered
can really help you out. Wind Control Devices,
stop the wind effects, improves thermal
conditions, doesn’t put the fire out,
that still needs to be done. Floor below nozzles, put
water on the seat of the fire, improved thermal
conditions doesn’t make the oxygen supply go away. Combining tactics,
works great if you can combine the
blanket deployment with the nozzle, get all these things
working together, but it’s extremely
labor-intensive. Each of these tactics
require staffing to implement. That’s something that
needs to be examined at the Fire Department level. Take it to the street. These guys are going
to talk about that. How many people does it take
to deploy these tactics, what staffing do we
have available, could that staffing be
used for other things? These are all important things
to take into consideration as you do your size-up and look at your resources
for these hazards. I am going to turn it
back over to the Chiefs and we are going to
wrap it up. I love this stuff. I mean, can you imagine telling
a bunch of firefighters, I got this great new
firefighting technique, we are going to block all
the ventilation openings, they’ll look at you like you
have got two heads, right? But you see, right? There is another one, I got this
great firefighting technique, we are going to throw
water on the fire from outside the
building, right, what did they tell you? You are going to push
the fire, guess what? It’s being pushed, pretty
effectively by the wind, right? Instantaneous
reduction, going from an un-winnable, un-fightable, unmanageable situation is
something we can deal with, with two really
simple techniques. I am going to put
the fire out first, but they are going to make
it fightable now, right, go from not fightable
to the fightable.

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