Salt Water

[JGallagher]

Yay, first post in new thread.


Down to the question. Why does salt water put out a Fire quicker then regular water? I heard this the other night but was not able to hear the answer.

[bfrd22]

I'm not sure about speed but the pumps are way more expensive as everything is Bronze or Brass. I now the pump is actually cast Brass to eliminate the corrosion problems. Big Bucks.

[WFD999]

I think I might have a answer for ya. Had to dig out the advanced periodic table for this. But here we go. Numbers quoted are at 1 atm and 25 deg C, and the temps quoted are to change from a liquid state to a gaseous one. Vaporization is the Kilo Joules (Energy)/Mole at Boiling Piont where we change from a liquid to a gaseous state. Heat is our catalayst. Salt is basically sodium (Na), water H20 Hydrogen and oxegen.

Boiling Piont * Vaporization

Hydrogen -253 C * Hydrogen 0.12 KJ
Oxegen -183 C *Oxegen 6.82 KJ
Sodium +883 C *Sodium 89.04 KJ

There is also thermal conductivity mesured in W/(cm K) W= Watt another way of mesuring work required (energy), (cm K)= 25 deg C at one atm.

Hydrogen 0.002
Oxegen 0.003
Sodium 1.41

So the way I read this info sodium "salt" is the tougher of the three elements shown. And so here I go with best guess is that salt to a certian degree acts as a natural foam.

Then agian it could be a urban legend because in the old days it was easier to use the pressurized soda tanks than the hand pumps. Anybody else wanna take a shot

[bfrd22]

wow

[bestcoast]

Man, WFD999 that was impressive. Complicated but impressive.....

[five_alarm]

Bit of a side note here.

This doesn't explain the extinguishing properties of saltwater, but it is another reason for using a saltwater system from the Vancouver City:

"...This system will be used to augment the fresh water supply system for fighting a large fire in the downtown peninsula or it is capable of pumping saltwater for firefighting in the event of a failure of the domestic water supply resulting from an earthquake or some other cause."

http://www.city.vancouver.bc.ca/fire/emerg_prep/dsp.html

"The pumping station itself is designed to withstand an earthquake up to 8.5 on the Richter scale."

Pretty impressive, you know we're due for the big one here.

[WFD999]

Give a firefighter time to think ya never know what will pop out. Scary EH :)

If the grey matter is holdin up Ok, I think I saw a vid on the Vancouver water system not only did they give themselves the ability to put the water system above ground but they took 4 or 5 of their old pumpers that were at the end of thier service life ripped out the 840 and 1050 pumps and put in 1850's they call em super pumpers. Some thing like that would be a gas to run.

[TiSme]

WOW ...... that's a definate gold star ... hehehe

Did you major in chem? It sure sounds good. :)

I have read a little on Super Pumpers .... rather an interesting idea. But I wouldn't want to be near a blow out on one ;)


Let's be safe out there!!

[ehetu]

Just came back from Florida where I asked a few local firefighters about whether they used special equipment to draft from saltwater sources... nope. They draft saltwater right into their pumpers and just wash it out with freshwater when done... which is exactly what my Timex says to do...

edmond
Chelsea

[bcfire]

WE RUN SALT WATER RIGHT TO THE PUMPS ALSO IF THE SOURCE IS AVAILABLE. AFTERWARDS A GOOD FLUSH WITH FRESH WATER IS NECESSARY.
TAKE CARE, BCFIRE

[firefighter9calt]

We have done the same if necessary. Not our first choice but you do what you have to.

[Hamp42]

Well, WFD 999, if you can't blind 'em with science, baffle 'em with bullsh*$.
Just kidding.
Being inland, salt water is not an option. But a good rinse would be needed after use.:) :D

[Michael13]

1 cubic foot of salt water weighs 64.0 lbs at 38 degrees F
1 cubic foot of fresh water weighs 62.4 lbs at 38 degrees F

Fresh and salt water take up the same space, but salt water is more dense. My text book doesn't say anything about salt water being better. I want to say that since its more dense, it makes more steam. But thats not true. 1 cubic foot of water makes 1600 CU. FT. of steam, fresh or salt water. So the only way salt water can be better is because it weighs more. Thus, it may have a greater force coming out the nozzle. and salt water will vapourize faster then fresh water, turning into steam faster.

[WFD999]

SHHHHHH. Hamp Dont tell everybody:D ;)