Reply
 
Thread Tools Search this Thread
 
Old 12 August 2006, 06:36   #21
Member
 
Country: Other
Town: Stanley, Falkland Is
Boat name: Seawolf
Make: Osprey Vipermax 5.8
Length: 5m +
Engine: Etec 150
Join Date: Mar 2006
Posts: 3,688
Quote:
Originally Posted by jwalker
I think that is true for Co2 but at close quarters, as might be the case in a rib, the cooling effect is substantial and if you release Co2 into a small fire there is often ice on the surface where the flames have been extinguished. Whilst displacing the air (hence oxygen) is a benefit, if you do a bit of research on the Halon replacement gasses, I think you'll find they do absorb heat. If they just displaced the oxygen, it wouldn't matter which inert gas was used.

I would guess that they initially remove heat to below a point of ignition then they prevent reignition by hanging around excluding the oxygen. As I said, just guessing.
No idea on Halon but I am pretty sure the cooling effect of CO2 is down to basic physics. You are rapidly boiling a pressurised liquid into a gas and therefore that absorbs heat - a bit like the principle an air con system works on I suppose.

I use CO2 bottles for my beer brewing at home and if you trigger the nozzle with your fingers you can end up frozen to it... the cooling effect is huge.
__________________

__________________
BogMonster is offline   Reply With Quote
Old 12 August 2006, 16:48   #22
Member
 
Country: Ireland
Town: Ireland , cork
Boat name: liberty
Make: lencraft
Length: 6m +
Engine: outboard yamaha 150
Join Date: Jan 2006
Posts: 57
AFFF Trash

The replacement for Halon is AFFF. But from my experience in motor sport AFFF does not even come close to Halon. For me it has to be Halon all the time.
__________________

__________________
sparkey is offline   Reply With Quote
Old 12 August 2006, 18:00   #23
Member
 
Country: UK - Scotland
Make: HumberOceanOffshore
Length: 8m +
Engine: Volvo KAD300/DPX
Join Date: Oct 2002
Posts: 4,962
Sparkey, maybe in motor sport the halon has been replaced by AFF foam but that is not what is commonly known as halon replacement. There are various gases and, I believe, some fluids which evaporate rapidly into a gas, and this group is the halon replacement we are referring to.
__________________

__________________
JW.
jwalker is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 00:48.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.