You don't want to mess with acetelyene, and there is not a lot you can do with it in these circumstances. Bomb disposal wont work - you can't do a controlled explosion on these things, or they would have done. At work, if we have a problem, call the fire brigade and run away!
As much as I think they close roads at a drop of a hat these days, they have it spot on in this case (these cylinders don't explode, they go off like torpedo's).
Joe
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Some of the mechanics made an Acetelyene bomb in te workshop last year, think it involved taking a baloon, filling it with Acetelyene in the same way that you would fill it with helium, attaching alength of toilet tissue to it and then getting someone who didn't know what was in the balloon to light it and run away.
Needless to say the massive bang was audible for quite some way around, it certainly sounded like a bomb going off, and I was in the showrrom part of the site.
That gas was exlpoded at not much more than room pressure, if a fully pressurised cylinder blew I can'[t imagine the devastation it would cause to the surrounding area.
Blue
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>>Some of the mechanics made an Acetelyene bomb in te workshop last year,
Some call it fun.I call it idiotic/dangerous to say the least.
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Steve
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(these cylinders don't explode, they go off like torpedo's).
Oooh - that sounds bad.
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As i predicted there was no explosion...
news.bbc.co.uk/1/hi/england/beds/bucks/herts/46570...m
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Nobody said there would be, merely that tehre could be.
Your problem is a deep need to blame and criticise the police at every turn. Still, that is your right - and seemingly also your habit.
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there's a regulation that says if there is a fire involving acetelyn cylinders then they have to be left for 24 hours.
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it all comes down to the interpretation of the rule aand the risk.
a little while ago, a company i am close to carried out studies for potential security risks posed by various daily activities such as jumbo-jets flying in/out of heathrow, tankers carrying lpg and lng in the english channel, etc.
the results of these, if given to the health and safety experts for interpretation and action, would result in an imediate shutdown and evacuation of london and southeast england.
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the results of these, if given to the health and safety experts for interpretation and action, would result in an imediate shutdown and evacuation of london and southeast england.
In that vein I read a spoof Health and Safety report about untrained operators pumping highly inflammable liquid into inadequate containers, in close proximity to hot machinery ? and often spilling this liquid onto the garage forecourt.
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So well done the police then for dealing with it in such a sensible and safe manner??
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>>As i predicted there was no explosion...
What would you have said if an explosion had occured.Could so easily have been
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Steve
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What would you have said if an explosion had occured.Could so easily have been
No different to the many car fires that occur on the M25 each year. Remember that a full petrol tank exploding would be probably the same effect as a gas cylinder. Driven past many car fires on a motorway hard shoulder with no attempt to close it by the police.
Easist way to deal with this situation, bung the cylinder in a skip full of water then place another skip full of water on top. Then it's protected by the thick steel that an unlikely explosion would not penetrate and the water would cool cylinder down rapidly.
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>>Remember that a full petrol tank exploding would be probably the same effect as a gas cylinder.
Doubt that but will leave it there!
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Steve
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>> >> What would you have said if an explosion had occured.Could so >> easily have been No different to the many car fires that occur on the M25 each year. Remember that a full petrol tank exploding would be probably the same effect as a gas cylinder. Driven past many car fires on a motorway hard shoulder with no attempt to close it by the police. Easist way to deal with this situation, bung the cylinder in a skip full of water then place another skip full of water on top. Then it's protected by the thick steel that an unlikely explosion would not penetrate and the water would cool cylinder down rapidly.
Thick steel on a skip? - have a look at a skip next time you walk past one. The sides are not thick at all. And if you "bunged" it in lengthways, there's the risk of the cylinder exploding, shooting forward and hitting the SLOPING end of the skip and going who knows where.
I'm sorry you got stuck in traffic, but honestly, try to let it go. It was a horrible situation that the emergency services reacted to in entirely the correct way.
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The subject of lengthy road closures after incidents is raised frequently in the Backroom.
There is little point in discussing specific incidents as we are rarely are in possession of all the facts.
Comment on this subject is invariably construed as a criticism of the police and the thread degenerates into an attack and defence of the police.
There seems to me no doubt that roads are now closed for much longer periods than yesteryear. Certainly far longer than in any country in which I have driven.
I have read that this is because of new police protocols requiring accidents involving injury to be treated as a crime scene, but have no idea if this is true.
Whilst no criticism should be levelled at police for carrying out their instructions, it surely is valid to ask, and discuss, if the protocols are a police initiative or a directive from their political masters.
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Whilst no criticism should be levelled at police for carrying out their instructions
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agreed. the problem is that most institutions have removed the right of employees to make on the spot assessments of situations and make common-sense decisions. there is rarely any room for initiative to be used and instead, employees are required to follow the script as laid down in tablets of stone by committes of "experts".
in this particuar case, "The police spokesman said under fire service and health and safety regulations acetylene gas must remain undisturbed and monitored for 24 hours after a fire."
no one in authority seems to have had the sommon sense to question why that should equate to an instruction to closing down a motorway.
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Welcome to the modern world. There is a book of rules, if you follow the rules then whatever happens you are covered. Don't follow the rules and something goes wrong and your for it.
That the rules make no sense in a situation is irrelevant, the rule is you follow the rules.
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I have no comment to make on the volatility or not of the acetylene cylinder and I have every reason to believe that the police and fire authority made the best decision they could in the circumstances.
I have no wish to knock the fire or police services who do a fine job under difficult circumstances.
What I do detest is the political correctness attitude which leads to these regulations being adhered to at all costs just because some little bureaucrat in Brussells or Whitehall decrees it.
There is a total lack of flexibility for the people on the spot to make a judgement without the threat of of being sued or dismissed by their political masters so the guy on the ground will do nothing.
These motorway shutdowns are regular and taking longer and longer , 8 hours, 12 hours, 24 hours shutdowns are now common and no longer even appear on the news.
I would like to see someone take on the police authorities in the court over the consequential loss suffered as a result of these decisions.
The incompetence shown by the highways people , the police and underground authorities in their planning and reaction to a snowfall in the Cutting Edge programme would have been laughable if it wasn't so serious.
One of the major problems was and still is IMO a total lack of communication between the authorities.
It is surely time to get some better organisation to plan for these not uncommon incidents such as RTA's and Snow.
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Its nothing whatever to do with "PC", in this instance, as there is a serious risk from acetylene cylinders which have been involved in a fire. If you can cool it, that helps to reduce the risk, but acetylene cylinders are unpredictable. If they are heated the contents decompose, adding to the heat, but from the inside. Could go within minutes, or could take a couple of days quietly heating up, weakening the pressure vessel its in. You can't risk moving it as that could aggravate the situation. The effects of an exploding cylinder can be widespread, so it really isn't safe to be near it. A petrol tank fire is relatively easy to deal with, as it has a soft shell.
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Imagos - You said you think a cylinder would explode with little more force than a petrol tank.
You are hugely wrong. Like I said, a child's balloon filled with just a small amount of that gas made a deafening blast when i heard it go off.
A higly compressed cylinder would be capable of destroying any building that it was in, and would obliterate any vehicles passing it at the time if in the open air.
Blue
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Actually, puttting the cyclinder in water would be one of the worst things you could do. The water would concentrate the power of the explosion, thus magnifying it. I saw a wonderful demo of this on TV where a chap put an explosive on a metal plate and detonated it. A bit of a warped plate resulted. Then, he put a similar plate + explosive in a water tank and detonated it. Huge hole in metal plate. I believe he was demonstrating the principles used in the Dambusters raid. So, if you did this and then put a skip on top you would simply be increasing the devastation, should something go wrong.
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Indeed. To concentrate explosive effects you need to contain the explosion. As the dambusters bombs did to crack the dams open, as is the theory of torpedoes and mines.
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We seem to have a lot of experts on explosive effects in the forum.
Water concentrating power of the explosive - interesting. Sure it deflects some of the force downward as water is denser than air.
Ever seen a hand grenade tossed into water? Kills the fish but not much shrapnel - in fact if the water is deep enough it hardly causes a ripple. Similarly 1lb of TNT in a 50 gallon drum filled with water causes surprisingly little damage.
However the police follow the instructions they have been given and I believe should not be ctiticised.
However, as said earlier, I do think it reasonable to debate the ever longer road closures for RTAs etc.
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Cardew - study the theory on how a relatively small amount of explosive cracked open a few hundred feet of damn. And how that theory is now being used in Explosive Forming or HERF (High Energy Rate Forming)
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Cardew - study the theory on how a relatively small amount of explosive cracked open a few hundred feet of damn. And how that theory is now being used in Explosive Forming or HERF (High Energy Rate Forming)
RF,
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Cardew - study the theory on how a relatively small amount of explosive cracked open a few hundred feet of damn. And how that theory is now being used in Explosive Forming or HERF (High Energy Rate Forming)
Whoops!
RF,
Ditto Depth Charges. Shock waves can cause damage - severe damage.
However you only have to see World War 2 footage of bombs missing ships by a couple of feet and doing no damage at all.
I am possibly one of the few who have some experience of using explosives.
I don't pretend to have any experience of gas cylinder explosions but I am sure I would rather be standing next to an cylinder immersed in water than an exposed cylinder.
Not that I am advocating that the police should have taken such action.
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the health & safety exec has a document
www.hse.gov.uk/pubns/indg327.pdf
"An operator was lighting an oxy/acetylene cutting torch. There was a flashback to the acetylene cylinder, which started to vibrate. Three minutes later the cylinder exploded. ........
The windows were blown out and the roof collapsed.
The explosion also lifted the roof of the main
factory building, which had to be replaced. The
cost of the damage was over £1 million. ....
To make an unstable cylinder safe, the fire brigade may have to
apply cooling water for many hours. It could be several days before the cylinder can be moved, because moving the cylinder could restart or accelerate the decomposition.
These incidents put at risk anyone in the vicinity of the cylinder and anyone who tries to make the cylinder safe, such as the emergency services. "
and from www.dhsspsni.gov.uk/niaic/mdea_updates/2004/MDEA(NI)2004_22.pdf
"... The Emergency Services are likely to enforce a 200 metre exclusion zone around any affected acetylene cylinders. (An exclusion zone is normally enforced for a minimum of 24 hours or until the Emergency Services determine that the risk of explosion has been removed). ..."
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Acetylene will explode with no external stimuli above 24psi. For this reason it is stored in solution with acetone, which stabilises the acetylene.
Now subject a cylinder, at much higher than 24psi, to fire. There is a danger that the cylinder may have leaked, or that the acetylene and the acetone have separated.
Acetylene has a calorific value of 56,000 per m3 (in free state) versus petrol at 48,000 per litre. There are a hell of a lot more m3 of gas in a cylinder than petrol in the average car fuel tank.
Now a car fire is a problem for an hour or so, but once the flames are out and the metal cooled, no more danger.
Acetylene is another matter. Once heated and in a possibly damaged cylinder, it could go "pop" in a most spectacular fashion. Very spectacular indeed.
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