handline that went to the exposure. The second line out was a
2½-inch handline with the triple stack smooth bore tip combination with the entire stack still attached to it. In other words, they
were using the one-inch tip and, if it was being pumped correctly, they were getting 210 gallons per minutes (gpm). Because
my wife and I have been married 35 years now, and I have been
teaching this subject for the same amount of time, she is semi-versed in what my concepts and theories are all about. So I asked
her: Is there anything else they could be doing that might put this
fire out faster and save the exposure? Without any hesitation, she
asked, “Why don’t they fire up the deck gun and blast the heck
out of it?”
AVOIDING THE BLAST
The concept of using large flow streams to put out fires is actually pretty simple and, as far as firefighting goes, is also pretty safe
for the firefighters. You’ve all heard the statement, “You have to
match the gpm to the British thermal units (BTUs).” I go one
step further and say that you have to overwhelm the BTUs with
A list of reasons fire departments do not practice the over-
whelming blast concept includes the following:
1. Firefighters do not understand their equipment and capabilities.
2. Firefighters don’t understand the fire science of overwhelming
BTUs with gpm.
3. Lack of training.
4. Lack of understanding of water delivery not just from the
discharge side of the pump but also in regard to water supply.
5. Firefighters tend to do what they have always done.
6. It’s not fun.
If your department is one that lacks sufficient water delivery for
large fires, I’m sure you can probably relate to some of these and
maybe others that I have not talked about. The bottom line: We
need to start thinking and practicing these big hits on certain fires
to do a better job of controlling and finally extinguishing the fire.
Here is my theory on exposure protection: If there is an exposure problem with first-in companies, there is a decision to make.
Do I protect the exposures with water application or do I knock
down the problem that is creating the exposure—the fire? If you
think that a direct attack on the fire can knock down the fire in
seconds to a point where it is not hot enough to impact the exposure, then go for it. If not, then the direct application of water
on the exposure is warranted. If you choose to hit the exposure
creator, then knock the snot out of it. Hit it with everything you
possibly can within your limitations.
I’d like to talk about two topics from my above-mentioned
list that will greatly improve the knockdown capabilities of large
fires. Usually when I discuss water delivery, I always start with
the water supply; however, in this article, I want to start with
required streams and then talk about developing the required
water supply to feed the streams. The reason for this is simple: A
lot of times bigger tips or larger flows are not used simply because
crews do not have the water to support them—or at least they
think they don’t.
Every apparatus should have at least one designated handline
that can be used for a large flow operation, whether it’s precon-
nected or simply stored in the hosebed. It should have a nozzle
that will flow a maximum amount of water based on equipment
and department policies. Here’s a good example: a preconnected
2½-inch handline, 200 feet long with the triple stack smooth
bore tips, which are all connected to the nozzle. I personally don’t
believe in the triple stack tip because even though it gives the
firefighter the opportunity to dial in the flow, it seems to never
happen. The entire stack is just about always left on the nozzle,
A 500-gpm master stream.
Multiple lines from the hydrant produce maximum flow.
Don’t use the entire stack; use the 1¼-inch tip.