I hired a van today to pick up some bits and pieces which involved a journey from near Braintree to just north of Colchester. About 8 miles from the A12 a traffic announcement blasted out of the radio (made me jump - didn't know it was on) saying that the A12 is closed in both directions for 24 hours!!
The cause? A van caught fire carrying gas cylinders. I was lucky enough to take the back roads but in doing so crossed the A12 3 or 4 times (lost) and I really felt sorry for the people stuck in horrendous queues.
But my question. Is this another one of those "functional creep" areas whereby fire + gas cylinders means immediate road closure for 24 hours. There seem to be more and more of these incidents recently and they don't register with me as happening so much 5 or 10 years ago.
If these things are that dangerous (and the vans carrying them that likely to spontaneously combust) why are they allowed on the roads?
I can't imagine what today's cost (money and accidents) of disruption was - a major road and main railway line closed for 24 hrs.
Paul
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A12 northbound and rail line now reopened.
Review at 07:00 on whether to reopen southbound at 08:00
Irony of this was that the vehicle involved was carrying oxy-acetelene kit and was a maintainance vehicle for ......... wait for it.......... Essex Fire and Rescue Service!!!!
Apparently the cylinder is capable of causing shrapnel damage at up to 175 metres away and it's only a 9Kg cylinder. At one stage the Royal Ordnance Corps bomb disposal unit from Colchester were onsite and were considering a controlled explosion to make it safe and get the road reopened.
The particular place this occurred probably couldn't have been worse for the impact on the roads in that part of Essex or the rail line into East Anglia.
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Yeah I wouldn't fancy being the first person to try and shift one of the cylinders if they haven't been given the proper time to cool down! :-)
One of the mechanics at a Fiat garage that I used to work for once inflated a balloon with oxy-acetelene, used a string of toilet roll to act as a fuse wire and lit it. The boom was deafening, I can only imagine what a pressurised cylinder would be like.
Blue
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when you see an oxy/aceteline flame backfire and then see the bagging smoking but know that the flame arresters will still save you is stil a brown trouser moment, so as regards meeting a hot cylinder of aceteline as a fireman is not worth all the tea in china.
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OK, so this stuff is highly dangerous. Where are all the incidents of this detonating, the fear of which has led to closures of main roads and railways for many hours? Something that never used to be the case.
If there have been lots of incidents then why is this stuff allowed on the roads in your average Transit? If it's going to be allowed then surely some specialist carrier?
It wasn't that long ago that the M11 was shut for hours and I think the A14 recently too.
I suspect it's just H&S running riot and to think it was a Fire Service vehicle involved in the A12 incident beggars belief.
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Maybe before it was rarely reported so you never used to hear of so many of these incidents as you do now? The actual gas/bottle doesn't detonate as such but if left in a burning vehicle then it could go off like a bomb.
It is allowed in your average Transit just like most other types of gas bottle, but what you do find is that some vehicles carry the stuff round all the time as it is a tool of the trade. For example, mobile vehicle repairers (commercial ones in particluar) often carry an oxy-acetylene plant around to allow them to do their job, which I would suspect is the case with this particluar Essex Fire and Rescue van.
What you have got to remember it is not the gas cylinder that is at fault, the fire is started by something else. The fact that the gas cylinder is in the van is an unfortunate coincidence.
Edited by Simon on 06/10/2007 at 10:59
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The main point here is that the the fire crew's knew what they were dealing with straight away i.e drive would know, cylinder woud be correctly marked etc. So the fire crew knows what it is dealing with.
One of the new developments I like is BP have brought out a Gas Propane cylinder made from a Glass Fibre mesh. in this case as it heats up in a fire little holes form to let the gas out and it will melt safely. As they say all clever stuff.
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I recall a tanker containing LOX or similar rolling on the slip road from the M25 eastbound (M26) to the A21 southbound turnoff - which is one of those dangerous ever tightening curves.
The emergency services just left it there for about two months until the thing was fully empty as if it ruptured then they would have been instantly frozen!
A fire engine stood guard a few hundred feet away and both were well off the road.
To be honest, gas cyclinders etc can be left until safe. It's a pain, but better than losing a life!
Edited by Zippy123 on 06/10/2007 at 13:57
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The gas pressure in gas cylinders is huge (80 bar, ISTR) and increases enormously if the bottle is heated. If the steel bottle breaks under gas pressure, it ruptures explosively, chucking bits of broken metal a long way.
There is often a pressure release valve at the top of the bottle, before the isolating valve;
They're not on all bottles, I don't know why. They relieve the pressure by venting gas if the bottle overheats, preventing an explosion. However, they sometimes leak on refilled bottles and can be easily be ignited by sparks from cutting work.
If the gas from a leaking valve ignites, you can't easily extinguish it; extinguishers and hoses are ineffectual. The isolating valve won't stop it. The valve won't reseal once the gas bottle has been in a fire.
The usual procedure is to evacuate everything for 100m. There was a fire involving a gas cylinder in a car repair shop in the railway arches approaching London Bridge in about June; there was huge disruption to rail traffic into London. Network Rail, or whatever, then banned the use of acetylene in their railway arches. This affected hundreds of workshops. What else are railway arches used for? It's probably put the price of car repairs up.
Local councils have started licensing oxy-acetylene cylinders, for a fee. Many plumbers have stopped using it.
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fire brigade last came to do an inspection of my place a year ago
i have propane/,oxy/acetaline and argon
i offered them a map of the location of all the cylinders as they dont move from their designated areas,their response was its a commercial property with bottles we wont go in they said
i asked them how they would put a fire out and they said the fire wasnt important but life was and they would fight it from the outside only until safe to enter
fair enough i think, life is too important, especially if its only a vw or a vectra inside,now if it was a ford i would be very upset ;-o
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This morning ,the news said A12 would be open at 10.30am. but entering the A12 at Copdock at 3.30pm. the matrix sign said A12 closed at Colchester-I diverted but does anyone know when it was re-opened??
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I did hear a snippet from the guy in charge on the radio who said that they were going to "review operating procedures" in light of the chaos caused. Apparently, had spraying it with water not worked, the next idea was to have snipers shoot the cylinders and blow them up. If you need somebody who can shoot straight Colchester is probably a good place to look.
It certainly caused an impressive amount of chaos - there were villages 20 miles away who only normally see 5 cars a day gridlocked with hundreds. I doubt there was a road or junction in Essex and a good part of Suffolk not noticing extra traffic.
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