ECN Forum Forums General Topics of the Trade General Discussion Area How do fire sprinklers really work? (OT?)

Reno:
After reading your response I was wondering if there were listings for these type of sprinklers as they don't seem to be in general use in my city. Here is what I found on the Internet.

International ships appear to be under the Safety rules of the International Maritime Organization which is one of those UN groups. Boat mist sprinklers have to meet rule IMO 800(19) and I think the coast guard of the flag country is the final AHJ for this.

For building sprinklers the UL listing number is 2167 and at least one major manufacturer had one shown for sale on their web page.

According to the page I was looking at FM and UL worked with the IMO on the tests so sprinklers may be listed meeting both standards.

Regarding your views on the instant experts I agree.

Our data center had salad bar cough shields installed over all the servers, tape silo's and disk packs to prevent water from hitting them if the sprinklers went off. The director of data processing did not want his equipment getting wet in a fire if the sprinkler(s) went off.

He is under the impression that with a dry pipe system all the heads go off as soon as the water hits the pipe. We tried to explain to him if one of the covered units has flames coming out the top, the plastic would catch fire, melt and make sure the sprinkler head over it opened.

Don't underestimate misting fire suppression systems. On a bet I put out a 5 gallon bucket full of water with burning diesel on top using nothing but a ZEP spray bottle. This was flames 5' high.
I had the nozzle cranked all the way down so it was shooting a fine mist. That water just sucks the heat out of the fire until it can't burn anymore.
It is something they taught me in the military to fight fires on ships. We used low velocity fog to control a diesel oil fire in a swimming pool sized tank and in a mock up of a ships compartment.

Supression is not life safety, Its main intent is property protection.

I've seen water mist work very effectivly. Very popular in the power industry for the gas turbines. It must be very well calibrated, (air/water mix).

The new data rms, paper is not protected, rather the electronics. This is the reason behind the gasses.

Halon is still out there. the systems can still be recharged, (if you can find and afford it). The systems can not be modified, no athaurity will honor the calculations.

Fm-200 ( AKA FE-227) Is the replacement. All new calcs and modifications are needed so basicaly a new system.
Halon takes 13 million yrs to break down, FM takes only 9 million.

A nice product out there is "Inergen", The draw back is it takes up a lot of space.

This is an inert gas combo. @ 2500 psi it must be throttled down on discharge.
It operates by displacing the room air with the gas (+- 80%)
It drops the oxogyn level to +- 12% and raises the co2 level to +- 8%, This will susstain life (no PI) but not support flame.

Due to the percentage pres. releif must be present (like dropping an ice cube in a glass, the excess (rm. air) has to be moved out. Hence the need for space, all those tanks.

dis claimer: I've been out of this end for 3 yrs, some things are newer, and my % may not be exact.

I may be going back to it soon coz it's one exiting feild.