Onboard fire suppression [Archive]

dazed driver

03-18-2009, 12:13 AM

What do you all recommend for a plumbed in fire system? I'd like a 3-4 nozzle setup, pointing at the engine, co driver, driver, and fuel cell. I also think I want to get a mechanical pull discharge.

Any opinions?

Audi UrQ

03-18-2009, 02:41 AM

If you can afford it, I think I'd actually recommend a dual system:
- Halon 1311 for the engine bay (if turbo car, mount nozzle directly above turbo, many fires result from a broken oil line spewing oil onto a hot turbo)
- AFFF for the passenger compartment

If you can only afford a single system, I'd probably recommend a Halon 1311 system, but try and ensure you have fresh air in the passenger compartment e.g. roof scoop and/or window vents.

And yes, I'd use a mechanical discharge system, that way if you have an off and/or a fire, you can kill the electrics and yet still discharge the fire system to attempt to put the fire out.

dazed driver

03-18-2009, 09:44 AM

Yeah, thats why I wanted them mechanical discharge. The car is NA, so, no turbo. And I'm not sure I can afford two bottles. Good idea though.

RichardM

03-18-2009, 01:56 PM

Has any one done a lot of research into the so called hydrocarbon encapsulating agents?

http://www.coldfirewest.com/

Carl S

03-18-2009, 03:52 PM

The electric units I've seen have a 9v to power them, so even without car power they'll still work. Had a battery test function too so you can test if the batt is good.

John Cassidy

03-18-2009, 05:17 PM

SPA Group N system. 5 nozzles. Electric or manual activation.

John

dazed driver

03-18-2009, 08:10 PM

How does electrical work? Does it sense smoke/heat?

John Sundelin

03-18-2009, 08:24 PM

No, you just push the button, and the battery gets used to initiate a small pyrovalve-type device. In my view, this is actually a slightly higher reliability device (when installed correctly and with a charged battery), but once you push the button, you're committed.

--
John

John Cassidy

03-19-2009, 07:34 PM

Not endorsing. Just a page with a copy of regs and many different systems.

http://www.spatechnique.com/product_pages/motorsportfiresystems.cfm

dazed driver

03-20-2009, 12:18 PM

Any reasons to go AFFF vs Halon or Halon vs AFFF?

RichardM

03-20-2009, 02:10 PM

Disregarding the cost of Halon since it is no longer made (there are other gaseous extinguishing agents available), the problem with it is that once it dissapates, the fire can reignite. As an example, consider an oil line at a turbo popping off. The very turbo can ignite the oil. If Halon or another gaseous agent is used, the fire will be put out but the oil is still present and the turbo may still be hot. Re-ignition can happen.

This can also happen with a powder if the oil or other liquid is flowing in any way. The powder gets washed away and re-ignition can happen.

Supposedly AFFF helps with this by lingering. The carbon encapsulating agents (Cold Fire) are said to complete eliminate the problem but I am not sure. Go to the SCCA emergency services forum and you can find a long debate on this.

DemonRally

03-20-2009, 03:50 PM

Halon is toxic...I don't see anyone staying in the burning car unless they are unconscious and generally you are going to have a bit more to worry about at that point....

RichardM

03-20-2009, 04:00 PM

Actually Halon is used in aircraft because you can breathe it and live. That is also the reason is was used in so many large computer rooms over the years. The other gaseous agent way back when was carbon dioxide. You can't breathe it. Today's gaseous agents still include carbon dioxide but also now include very high nitrogen content. The human body can live on less oxygen in the air than fire can. Halon does give off chlorine gas as a by-product of extinguishing fire but it is in low quanity.

ETA: Go here for more information - http://www.h3rcleanagents.com/support_faq_2.htm

dazed driver

03-20-2009, 09:26 PM

Well, the bigger reason they use halon in server/computer rooms is because it wont fry all the electronics like an AFFF will. Or sprinklers. And a dry chem will just make a mess.

RichardM

03-21-2009, 06:01 AM

Having designed many, many computer rooms including the fire supression systems, Halon was used because it is breathable and clean. Carbon dioxide is equally clean but not breathable. My recommedation to clients today is to use water. Any fire capable of setting off the supression system has already emitted enough smoke particles that every piece of equipment in the room is suspect anyway.

starion887

03-21-2009, 07:06 AM

John Cassidy

03-21-2009, 07:16 AM

Mark, I had an experience with my electric system not functioning well. BUT, it wasn't a trigger issue, it was a hose issue.

The push-lock connectors on all junctions need to be seated firmly. Any leak in the system will let the suppressing material escape there and cause a failure to pressurize the other branches of the line. How to test? I don't know, short of assembling the lines/nozzles with extreme care and possibly blowing some compressed air through the lines.

I had a mechanical system in the past, and had some corrosion in one of the cables, making it impossible to activate the system. I'd suggest that anyone with a mechanical system remove the cables from the sleeves each season, inspect and lube.

John

RichardM

03-21-2009, 09:49 AM

http://www.sccabb.com/forum_posts.asp?TID=3398&TPN=2

for a discussion like this.

dazed driver

03-21-2009, 10:27 AM

RichardM

03-21-2009, 12:28 PM

I've noticed Charles generally knows what he is talking about. I am going to fit a supression system in my car one of these days just so I can put NOS stickers on the tank. :)

Mike Hurst

03-21-2009, 01:46 PM

Water based AFFF systems are a bad idea for a rally car at Sno*Drift, or LSPR, or 100AW, or Perce-Neige, or....

dazed driver

03-21-2009, 02:00 PM

Water based AFFF systems are a bad idea for a rally car at Sno*Drift, or LSPR, or 100AW, or Perce-Neige, or....

Thats a good point. Even if under pressure in the tank its liquid, when it discharges, it will freeze after leaves the nozzle. Snow maker anyone? haha

Mike Hurst

03-21-2009, 02:35 PM

Thats a good point. Even if under pressure in the tank its liquid, when it discharges, it will freeze after leaves the nozzle. Snow maker anyone? haha

I'm more worried about the bottle being frozen solid from sitting in cold weather overnight. Many rally cars (especially open class cars without heaters) don't get warm enough inside to thaw them out.

Bruce

03-21-2009, 04:19 PM

Several of the post here hint at what I would consider a drawback of an onboard system - the inability to test it easily...coupled with the "out of sight, out of mind" syndrome. With handheld extinguishers, tech inspectors and the competitors themselves can shake them, check the gauges, and be pretty sure they'll be able to put out a fire.

Bruce

dazed driver

03-21-2009, 09:10 PM

I'm more worried about the bottle being frozen solid from sitting in cold weather overnight. Many rally cars (especially open class cars without heaters) don't get warm enough inside to thaw them out.

You think they could do that? I just figured they had enough pressure not to be able to freeze solid. I dont know though. Good concern though, cant put a fire out with an ice cube in a tank.

starion887

03-22-2009, 06:09 AM

I had a mechanical system in the past, and had some corrosion in one of the cables, making it impossible to activate the system. I'd suggest that anyone with a mechanical system remove the cables from the sleeves each season, inspect and lube.
John

Good point and experience to share; thanks, John.

Mark B.

RichardM

03-22-2009, 04:47 PM

I asked the question on the SCCA forum mentioned above. The answer came from a fireman in New Hampshire. They still carry aqueous extinguishers even in the winter. They will withstand 20F for about 5 hours before freezing. Therefore, probably not suitable for LSPR, Sno*Drift, Canada at any time :) or even Ojibwe. Fine for Rallye de Paris though.

Mike Hurst

03-22-2009, 07:38 PM

You think they could do that? I just figured they had enough pressure not to be able to freeze solid. I dont know though. Good concern though, cant put a fire out with an ice cube in a tank.

Typical AFFF race car systems are not pressurized, they use a CO2 propellant cylinder to aerate the AFFF foam
solution which is stored @ atmospheric.

I asked the question on the SCCA forum mentioned above. The answer came from a fireman in New Hampshire. They still carry aqueous extinguishers even in the winter. They will withstand 20F for about 5 hours before freezing. Therefore, probably not suitable for LSPR, Sno*Drift, Canada at any time :) or even Ojibwe. Fine for Rallye de Paris though.

Firetrucks get parked inside heated firehouses...maybe not in Texas (have they discovered fire there yet?) :), but for sure in New Hampshire!

There is anti-freeze available for some systems.

John Sundelin

03-24-2009, 08:54 PM

I was convinced to favor mechanical triggers by a experience of a friend with a Sports 2000 system. His electirc trigger failed when he pressed it several times for an on-track fire, and then went off on it's own....AFTER the car was over 90% destroyed.

John S., whay do you think electric is more reliable than mechanical? Just curious; you probably know something we don't.

Regards,
Mark B.

John Cassidy's experience is a good example of the primary reason that I would be leery of a mechanical system. However, after thinking about it some more, I think a well maintained mechanical system is probably better than the electrical. The control units that I've seen are generally not designed very well from a reliability perspective, and there are a couple of reasons why the actuator itself may not perform as reliably as it could (I might get in trouble for elucidating them on a public forum, so I won't). On the other hand, I have no doubt that I could build one that is more reliable than any mechanical system for about $15k!

--
John

randyzimmer

03-25-2009, 07:08 AM

Actually Halon is used in aircraft because you can breathe it and live....[/URL]

Here's a self-serving paper by a DuPont chemist that could use an editor.
It isn't as cheery about the breath-ability of Halon.

[URL]http://www.nfpa.org/assets/files//PDF/Foundation%20proceedings/Hammel.pdf (http://www.h3rcleanagents.com/support_faq_2.htm)

Even open F1 cars had medical air piped into the helmets when using Halon.

Eric Burmeister

04-01-2009, 09:26 PM

Here's a self-serving paper by a DuPont chemist that could use an editor.
It isn't as cheery about the breath-ability of Halon.

http://www.nfpa.org/assets/files//PDF/Foundation%20proceedings/Hammel.pdf

Even open F1 cars had medical air piped into the helmets when using Halon.

There are some "facts" in there that are preeety wrong, no?