automatic fire extinguisher, non powder

My understanding is that you don't mix media. So when I fit my foam firetec system, I'm getting a foam handheld to go with it.

 

thats right bay birmingham. dry powder and foam dont really mix. next time you have a bath use some bubble bath and shake a small amount of talc on it. its the same as what happens with dry powder and foam.
the beauty of foam is that it can be used on pretty much everything too. stick to 1 media and in my opinion that is foam. its what we use on our fire appliance for nearly all fires nowadays.
dry powder is great for a quick nock down, and we quite often sit a dry powder extinguisher in front of cars involved in rtc's incase the unthinkable happens, but we also have 1000's of litres of foam ready as within seconds the fuel will reignite.
i'm not saying the fire extinguisher bloke is wrong as dry powder is brilliant, but in my opinion foam is king

 

a thing about powder i remember in a fire course i went on years ago was the fact they showed that in the right (wrong) circumstances powder itself can explode, just like flour in a mill years ago used to do, now i'm not an expert and dog obviously is but i wanted foam as an auto one in the engine bay but i'm still having no joy (other than firetec buy) of finding one.....

 

then buy a firetec one

 

not auto, but
http://www.fireprotectiononline.co.uk/foam-fire-extinguishers/

 

yeah seen them mate, stand alone extinguishers not a problem got a guy at work to sort me out there, just struggling to find an auto foam.....must be a reason they all seem powder.

 

lighter and cheaper!

 

guess so mate.

 

here's a video of a foam v drypowder:

Fire fighting - Dry powder & Foam on oil Spill

As Dog says and you can see from the video the dry powder knocks down the flames really quickly.
The foam takes longer and needs more care to apply.
However the drypowder doesnt prevent reignition as well as foam.

Things I'm concerned about:

For the same size bottle in a closed environment being delivered through a statically fixed system which would perform the best?
Is it possible that the foam would run out before it knocked the fire down?
Dry powder does prevent reignition but not as well as foam, however, if you knock the fire down quickly there is a lower temperature therefore less chance of reignition isnt there, especially within a closed space?

I havnt found anything that says you can't mix media...

If you have a 240 hook up in the engine bay then powder in a suppression system is essential off course.

Blooming complicated all this fire stuff!

Cheers
s

 

Cheers for the top tip Dog. I need to replace my powder one in the bus with foam when I swap the engine extinguisher units over.

And having spent the day cleaning up a powder extinguished fire I too can say that it's very messy, smelly and seems never ending. I'm sure the engine is going to puff out powder when we get it started.

 

powder doesnt really cool too much hence the threat of reignition. with the firetec ones the tube melts at the seat of the fire so the media is applied directly to the seat of the fire(powder or foam!). as i said about mixing media, try blowing talc on bubble bath bubbles, its the same thing!
if you choose to get powder, then do buddy, it will work! just get a 2nd powder extinguisher as a back up and stop gap whilst waiting for the neenaws to arrive. and bear in mind that this could take a long while, especially in rural areas!

 

What I've learned from this is that its best to have both. That's why I have both & a fire blanket & a large CO2 one. C

 

watching the video where the guy reignites the powder one again interests me, would an extinguished fire reignite itself if the source of ignition was removed? as we see in the video he uses another flame to reignite the fire, would the heat from an engine reignite the engine if it had been put out by powder? also the example on the video is outside where there is a plentiful ammount of oxygen, it is more restricted in the engine bay but i'm unsure if it makes that much difference? would be very interested on your response dog as you deffo have more experience due to work.

 

AFFF (Foam) was all we used on helicopter fires, and is what you always see in plane movies, and also, on rare occasions, powder can settle in the extinguisher, and all the contents may not be available for usage. We was always told to invert once a powder before use. We had to rely on our own fire fighting skills, as 999 was no use in the middle of the Atlantic.
At the end of the day, the decision is yours, and cost will always be a big factor, until after the event