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Halon - Commission to propose remove aviation's critical use exemption

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Halon - Commission to propose remove aviation's critical use exemption

Old 1st May 2009, 20:32
  #21 (permalink)  
 
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CeeDee,
Try this; in addition CO2 discharges can creat a static discharge which can re-ignite a fire. Not very helpful when your last extinguisher is almost empty! In a confined space like a pax compartment in an A/C a large CO2 discharge will suffocate many of the pax.
As for water, not a goer as water and electrical cables/switch gear don't mix. Understand the Halon environmental case but still required in an A/C, find it difficult to understand why the EU have taken this line of action, no Engineers or Pilots amongst them!. Obviously none of them have had to put a fire out in a confined space. They want to attend some of the Fire Schools up here in Scotland, it would put the fear of God into them. In the offshore world all folk have fire fighting skills checked out every 4 years until they retire. No pass? No job!
Halon and its replacements(Larry Lippman, Mike Weihman, Urban Fredriksson)
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Old 1st May 2009, 20:55
  #22 (permalink)  
 
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Oilmandgasman,
Thanks for the link, filled a couple of gaps.
CJ
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Old 1st May 2009, 20:59
  #23 (permalink)  
 
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ceedee,

I've seen a very good demo of CO2 vs. Halon. It was a large grid of briquets, arranged so air could circulate freely. Once lit, it REALLY didn't want to go out. Water had no effect but create loads of steam. CO2 appeared to put the fire out, but it re-ignited almost instantly the CO2 blast stopped. Blasting with CO2 from a large cylinder for about 3 minutes, then dousing with water to help cool, which would have dealt with most fires, made it steam for about 10 seconds before it ignited again.

After this, the smug demonstrator, walked up with a smallish HALON extinuisher and gave it a 10 second blast.......then calmly walked away.

Job done.

HALON will travel down a confined space, when squirted at one end of a tunnel, it will put out the fire at the other. It reacts chemically with the fire somehow and in my view is PFM. I wouldn't sit in an aircraft without it!

As stated above, lets get the Commissioners to go see a demo at an Airport Fire Training unit. It would certainly open their eyes and wake them up some.
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Old 1st May 2009, 21:21
  #24 (permalink)  
 
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After this, the smug demonstrator, walked up with a smallish HALON extinuisher and gave it a 10 second blast.......then calmly walked away.

Job done.
Many years ago I attended a really basic fire fighting course ( how to use various types of extinguisher in office type environments)
Standard aircraft seats were set alight and a pair of attendees used CO2 to extinguish it.
The seats were relit, next pair used CO2 etc.
The fire was progressively more difficult to deal with as the heat was building up.
I used a quick squirt of HALON and out went the fire. I was very very impressed.
The instructor did impress on us that the job was not complete until the heat was also removed from the seats.

I immediately went and bought a HALON extinguisher.
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Old 1st May 2009, 23:06
  #25 (permalink)  
 
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Having each year during the SEP refresher seen the effectiveness of Halon I was disappointed when British Waterways removed Halon (BCF, bromodicholinefluridemethane??) from the waterways.

All our BCF's (having been replaced with dry powder) were then brought home where (illegally I am told) they sit in the kitchen etc as the very best extinguisher when (and if) that fire breaks out.

So far so good, no fires, no effect on the Ozone layer, but if.....

PS what about the channel tunnel, will they be replacing all their Halon extinguishers?
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Old 2nd May 2009, 00:23
  #26 (permalink)  
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Halon 1301's weight is what makes it effective and safe, it weighs about twice that of C02. It is all about smothering while keeping the likelyhood of it suffocating all the pax to a minimum.
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Old 2nd May 2009, 01:04
  #27 (permalink)  
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Halon Fire Extinguishers

It's right up to a point to refer to the high density of halogenated hydrocarbons as an important factor in their efficiency as fire extinguishers but it's not the whole picture. They don't just work by blanketing and excluding the O2, they also work by scavenging the free radicals inherent in any flame stopping the chain reactions inherent there and it's that that gives them their measurable performance edge.

However and by definition, their ability to generate halogen atom competitor free radicals is what also causes them to damage (ie reduce the concentration of) ozone in the atmosphere.

To me it's a simple risk/benefit analysis, I have a Halon extinguisher in the kitchen.......yes I keep weighing it.

The problem is that the people coming up with these actively dangerous suggestions are "critical thinkers" unencumbered by the burden of an inconvenient data base of experimental results.

Put more simply, they don't know enough.

CW

Radical (chemistry) - Wikipedia, the free encyclopedia
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Old 2nd May 2009, 08:14
  #28 (permalink)  
 
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Lightbulb

Perhaps our green regulators should take their initial cues from Mr. FlexibleResponse's fine reply.

They should then consider weighing the damaging effects to the ozone layer from 2 bottles of halon being released as compared to the effect the ignition and incomplete combustion of 50 plus odd tons of kerosene along with plastics and various and sundry other materials would have on that 'precious' layer of our atmosphere.

To make the comparison more realistic, the bureaucrats should also be encouraged to include things like their wife's favorite perfume and child's preferred stuffy fluffy bear in the fiery mix.
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Old 3rd May 2009, 16:39
  #29 (permalink)  
 
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Maybe someone has shown the EU commisioners this: http://www.eclipseaviation.com/files...hite_Paper.pdf
A fire extinguishing agent that is more effective than Halon with zero environmental impact is hard not to justify!!
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Old 3rd May 2009, 18:36
  #30 (permalink)  
 
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It was interesting reading the paper at the link provided by bizjetjock, they do seem to have done their homework re extinguishing engine fires, but I didnt see any mention of its use anywhere else on the aircraft, or did I miss something? I'm not sure it would read across all areas, of course it might, but feel free to correct me.
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Old 3rd May 2009, 19:09
  #31 (permalink)  
 
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Maybe someone has shown the EU commisioners this: http://www.eclipseaviation.com/files...hite_Paper.pdf
A fire extinguishing agent that is more effective than Halon with zero environmental impact is hard not to justify!!
Interesting article, although I am intrigued into the substance they are using, PBr3 . Bit of a nasty chemical that will hydrolyse to phosphorus acid which will then thermally decompose to PH3 which is highly explosive in air !!!
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Old 3rd May 2009, 20:38
  #32 (permalink)  
 
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Originally Posted by Biggles225
.... I didnt see any mention of its use anywhere else on the aircraft... I'm not sure it would read across all areas...
Originally Posted by Ex Cargo Clown
PBr3 . Bit of a nasty chemical that will hydrolyse to phosphorus acid which will then thermally decompose to PH3 which is highly explosive in air !!!
Same thoughts here.
So far it sounds like a path worth pursuing, rather than the panacea they make it out to be...

CJ
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Old 4th May 2009, 08:45
  #33 (permalink)  
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Ref recent Boeing Service Letter (15th april 2008) recommending not to use Dry Chemical Extinguishers (Not only in-flight but also in aircraft maintenance hangars and at airports).

Apart from poorer fire fighting capability, there seem to be signifcant risk of corrossion and damage to airplanes/equipment quote 'All of these dry chemical agents are corrosive and abrasive, and may cause moderate to severe damage to aluminium alloys abd electrical/electronical equipment'

It then goes on to read quote 'The use of dry chemical extinguishers can potentially cause more damage to airplanes and airplane electrical/electronic systems than an actual fire'
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Old 4th May 2009, 19:56
  #34 (permalink)  
 
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Many thanks for the links to all the documents. It made fascinating reading.
And to this layman, there seems absolutely no doubt that Halon is better suited for aircraft.
I'll live in hope that a passing journo will pick up on this...
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Old 4th May 2009, 22:02
  #35 (permalink)  
 
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Halons

Inhibitory factors for halons are in low percentages, trouble is CBM was less than 4 percent in air but very poisonous. Older guys will remember CTC! Better ones only need 5.2% in air whereas CO2 may require 30 to 70 percent depending on risk and needs a warning above 4 percent concentartion to avoid suffocation. I hope they will see their deluded thinking will potentially be a greater risk than any to the ozone layer. We should protest very strongly by all means possible. ( I may be a bit behind the times now as a lowly CPL but was in UK fire service for 20+ years and in terms of an operational and dynamic risk assessment I could only recommend Halon for aircrew - I stand by to be educated!)
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Old 4th May 2009, 23:15
  #36 (permalink)  
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PBr3 v Halons

http://www.eclipseaviation.com/files...hite_Paper.pdf

Good to read this, it really is trying to address the issue of the generation of politically correct Br atoms/free radicals in situ.

But ......PBr3 truly is a nasty and a real issue in terms of long term storage et al, its hydrolysis products eat metals and yes I know its redox really.

It's almost worth considering using liquid elemental bromine instead, properly toxic of course but not as prone to reacting with water if it leaks - just reacting with metals and people I know. My Pat Pending please.

Halons are pussy cats by comparison and far more reliable over time; my Halon extinguisher is still in the kitchen .............

CW
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Old 5th May 2009, 08:02
  #37 (permalink)  
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Quote from the note sent by the Commission (DG Environment) to the EU Member States which is nothing else thant a blund lie about the challenges to replace Halon portable extinguishers in aircraft. It seems that the Commission does not care about reduced aviation safety margins (due to less effective fire fighting capabilities), does not care about the increased weight (and associated fuel and co2 emissions - this for a negligable benefit for the ozon layer taking into account low amount of halon emissions by aviation) and off course does not care about the cost for the airline industry.

quote'

With few exceptions, new civil aircraft are still being designed and built with halon critical use systems and portable extinguishers on board. However, two fluorocarbon alternatives (HFC-227ea and HFC-236fa) which meet sector-agreed minimum performance standards are currently available for crew compartment and cabin portable extinguishers (4.2) and lavatory waste receptacle fixed systems (4.5). No technical or economic barriers exist to replacing the halon lavatory waste receptacle systems in new aircraft. Some additional costs would be incurred in replacing halon cabin portable extinguishers. The commercially-available alternative portable extinguishers that utilise these two substances are larger and heavier than the halon equivalent, and their adoption would likely require additional training for cabin crew. However, they are considered to be feasible options for this application. Other substances may also prove suitable if submitted for minimum performance standard testing.

Based on this note the Commisison proposes to ban Halon for portable extinguisher in new production aeroplanes from 2011 and propsoes retrofit by 2020....
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Old 7th May 2009, 10:37
  #38 (permalink)  
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Brussels ignores Halon ban safety fears!

DATE:06/05/09
SOURCE:Flight International

Brussels ignores halon ban safety fears


By Aimée Turner

European nations are being urged to reject official proposals from Brussels to ban halon fire extinguishers on board aircraft because they dangerously downplay safety concerns.

Industry says Brussels is determined to override international safety standards and ignore crucial concerns over replacing halon in aircraft extinguishers with a carbon dioxide alternative, which it believes to be inferior.

The European Commission's environment directorate recently launched a formal process asking European Union environment ministers to help review current rules on substances that deplete the Earth's ozone layer including halon-based extinguishers that are exempted.

"The official proposals that were sent to the member states in late April for comments with additional background seem to confirm that the environment directorate is trying to downplay the cost impact and safety concerns," says the Association of European Airlines, which has led industry lobbying on this issue.

Included in the proposals are the retrofit of portable fire extinguishers by 2021, of waste tanks by 2017 and all other halon-based systems such as cargo, engine nacelles, auxiliary power units and fuel tank inerting by 2031. Halon would also be banned in all portable fire extinguishers, waste tanks, fuel tank inerting, engine nacelles, APUs in new aircraft by 2012 and cargo compartments by 2017.

The AEA says Brussels is ignoring the well-founded concerns of the entire civil aviation industry, which insists there is still no halon alternative in APU, engine and cargo fire-suppressant systems while hand-held fire extinguishers that can use alternatives are significantly less effective, require more firefighter training and are considerably larger and heavier, increasing fuel burn and requiring costly redesigns.

"It seems Brussels is willing to comprise on aviation safety, does not care about the cost impact and is even willing to comprise its own anti-climate change objectives for a purely political agenda on halon replacement. We therefore need to make sure that EU member states reject those proposals.

"No dates should be decided - not even for new production aircraft - before safe and viable alternatives are available and the focus should be on further research," says the AEA.

Member states will submit their comments by 31 May. A vote is planned for October.
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Old 6th Jun 2009, 08:58
  #39 (permalink)  
 
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Alternatives in use in Fire & Security Industry

FM200
®
FM200® (HFC 227ea) is known chemically as Heptafluoropropane and is manufactured by Great Lakes Chemical Corporation.
FM200
® is a colourless gas which is liquified under pressure for storage. Like Halon 1301 it has a low toxicity level and is superpressurised with Nitrogen to 24.8bar (360psi). It rapidly extinguishes most commonly found fires through a combination of chemical and physical mechanisms.


Environmental Features
FM200


® contains no bromine or chlorine and therefore has zero Ozone Depleting Potential (ODP). The atmospheric lifetime of FM200 ® is between 31 and 42 years which along with its zero ODP presents a long-term solution to fire protection requirements.
Safety
FM200 ® has been found to be less toxic than Halon 1301, which makes it safe for use in the fully automatic mode in occupied areas. Typically FM200 ® requires a design concentration of 7%, which is



well below the 9% No Observable Adverse Effect Level (NOAEL) on cardiac sensitisation. The NOAEL for Halon 1301 is only 5% (the same as its design concentration).
Applications
FM200 ® is immediately available to protect most hazards



traditionally protected using Halon 1301. It is effective in the protection of data processing, telecommunications and electronic equipment as well as most flammable liquids and gases.
Replacing Halon with FM200
Existing Halon and CO2 control systems meeting the requirements of the relevant national or international standards are ideally suited for use with FM200 and can be modified to operate
as part of an FM200 system. Due to the differences in concentration and physical characteristics between the gases it will be necessary to change the container valve and nozzles and probably the pipework and
storage containers in carrying out a retrofit of an existing system. However, due to the similarities in the equipment, changing from Halon or CO2 to FM200
® can be accomplished with minimal disruption and little or no system downtime.





CARDIAC SENSITISATION
No Observed Adverse Effect


Storage
Compared with Halon 1301, FM200 ® systems require minimal additional floor storage space, if any. The physical properties of FM200® together with its efficient extinguishing capabilities allow it to be used in similar types of equipment to Halon. As the extinguishing abilities of FM200® determine that only 70% more agent by weight is required, the demands for additional storage space requirements are minimal.


Halon Recycling
We have invested in Halon recycling facilities and is able to decommission existing systems in an environmentally responsible manner.



Excuse the font changes....



Last edited by Golf_Seirra; 6th Jun 2009 at 09:12.
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Old 6th Jun 2009, 09:07
  #40 (permalink)  
 
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More Alternatives...

ENVIRONMENTAL IMPACT

PYROSHIELD agent is a mixture of two naturally occurring gases; nitrogen and argon. As PYROSHIELD agent is derived from gases present in the earth’s atmosphere, it exhibits no ozone depleting potential, does not contribute to global warming, nor does it contribute unique chemical species with extended atmospheric lifetimes. Because PYROSHIELD
agent is composed of atmospheric gases, it does not pose the problems of toxicity associated with the chemically derived Halon alternative agents.

PRODUCT DESCRIPTION

The PYROSHIELD Fire Suppression System, manufactured by AST (PTY) LTD, is an engineered system utilising a fixed nozzle agent distribution network. The system is designed and installed in accordance with the National Fire Protection Association (NFPA) Standard 2001, “Clean Agent Fire Extinguishing Systems”. When properly designed, the PYROSHIELD system will extinguish surface burning fire in Class A, B, and C hazards by lowering the oxygen content below the level that supports combustion.

PYROSHIELD agent is a mixture of two inerting (oxygen diluting) gases: 50% nitrogen, 50% argon. PYROSHIELD gas extinguishes fire by lowering the oxygen content below the level that supports combustion. When PYROSHIELD agent is discharged into a room, it introduces the proper mixture of gases that still allow a person to breathe in a reduced oxygen atmosphere. The normal atmosphere in a room contains 21% oxygen. If the oxygen content is reduced below 15%, most ordinary combustibles will cease to burn. PYROSHIELD will reduce the oxygen content to approximately 12.5%.

Basic Use
– The PYROSHIELD system is particularly useful for suppressing fires in hazards where an electrically non-conductive medium is essential or desirable; where clean up of other agents present a problem; or where the hazard is normally occupied and requires a non-toxic agent.


All normally occupied or unoccupied electronic areas where equipment is either very sensitive or irreplaceable




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