Acetylene Cylinders - Recent fire at King's Cross, London

[John Webb]

The recent fire in a building site involving acetylene cylinders next to King's Cross station caused this station to be closed for understandable safety reasons. But the closure caused considerable problems to many thousands of people for a couple of days until the cylinders were safe to remove and the station could be reopened.

Over twenty-five years ago I was reading in American journals of techniques to render safe from a distance these and other gas cylinders affected by fire by using armour-piercing bullets to puncture the cylinders and ensure that they could then freely vent and could not build up pressures that would cause a dangerous explosion.

Has this technique ever been used in the UK? Is it still used in America? Is there any other way such cylinders can be rendered safe quickly (and with safety for firefighters) to minimise the disruption to those who need to use buildings that would otherwise be closed?

[wee brian]

John

I'd love to see the risk assessment. As any ex serviceman will tell you a High Velocity bullet is still lethal after traveling over three miles!  Best you are a good shot!!!

[John Webb]

When I was reading about this, the American fire service was working usually with their local police sharp-shooters who actually fired the bullets. As I recall the principal advantages were seen as:
1. No-one had to go within a couple of hundred yards of the cylinders to do the job, other than to place any initial cooling sprays/fire-fighting jets in place and then retire.
2. You were certain that the cylinder could not explode becasue it was well-vented.
3. Consequently the fire scene could be accessed sooner to ensure all was extinguished.
4. The safety zone could be reduced or eliminated quickly to minimise disruption to surrounding properties.

I don't recall what the safety procedures were - this problem was not a primary concern of mine at the time and it was only the principles I recalled. I raised the topic as a result of reading comments on another web-site of those interested in railway operations but without knowledge of fire service procedures.

[messy]

I reckon that the concept should continue to be a balance of securing the safety of the FFs/locals and prevent property damage.

With the John Wayne approach, whilst the public safety could be satisfied, I am not sure I'd be happy for my building to be needlessly damaged, when the alternative (ie waiting) could satisfy both requirements.

In addition, the Kings X cross incident was unusual as any sniper would have a fairly clear view of the cylinders as they were on the top of a tall service/liftshaft being constructed. This is not usually the case as most cylnders are found in workshops or other locations which would (I imagine) pose difficulties for sharp shooters.

This is not a fire service problem, it belongs to industry. I'd be interested to know what started the Kings X fire. I assume from the time of day and location, that arson is least probable.  I suggest that, in most cases, better training (how many workers fully understand the dangers of acetylene!?) and supervision of building sites can often may of prevent such fires

Perhaps if fire safety arrangements/legislation was tightened in such environments (ie where acetylene is used or stored) , industry would be more encouraged to find alternatives to using acetylene.

[wee brian]

Waiting can be very expensive sometimes. consider a van fire on the M1 or having to close down a major railway station. This costs our economy zillions of pounds.

Of course it would be better if they didnt have a fire in the first place or that they used something other than acetylene. But arent all fires/road crashes ect not a fire service "problem". (excluding the odd loony who starts fires because he likes to put them out).

Perhaps in the right circumstances a rifle bullet would be OK. There are other ways though, bomb disposal guys use a gadget that blasts water at high velocity that would do a similar job. You need to place it using a robot but there is much less risk of a ricochet taking out some poor so and so half a mile away.

[Mike Buckley]

I don't think that water at high velocity would do much to a gas cylinder appart from knock it over. Having seen the bomb disposal guys in action, yes they use the robot, but there are plenty of areas where the robot cannot go and then it is back to the man in the bomb suit.

Yes waiting can be expensive, but so can funerals.

[wee brian]

trust me at the pressure they use it water cuts through steel plate like it's butter (its a bit more than a jetwash!!)

I think we all agree that there is a shopping list of rifle/robot/wait - depending on the location of the cylinder - funerals should be avoided.

[John Webb]

Possibly use the 'water slug' method from bomb disposal robot to knock off the regulator/valve assembly from the top of the cylinder? But possible the opening left would not be an adequate vent to prevent pressure build-up?

I agree that prevention of the incident in the first place is better by far.

[Edward]

what is the procedure in the uk to cool down such cylinders? as we've not been trained in such a situation, noone mentioned it to us at least

[AnthonyB]

You need to refer to
Fire Service Manual
Volume 2
Fire Service Operations
Acetylene Cylinder Incidents

40 pages of protocols!

If you have trouble getting hold of a copy let me know & I'll see what I can do

[messy]

Zeromike

Basically, Establish a 200m radius restricted area. Place cooling jets (tied off) and cool for 24 hours. If this is impractical (poor access, environmental or salvage issues or poor water supplies) leave for 24 hrs with no cooling.

After 24 hrs, check the cylinder stays wet when water turned off, cylinder 'looks' cool with a TIC, and feels cool to touch. If any of these tests fail, it's another 24 hrs of cooling and maintaining the restricted area.

That's the main bits

[Edward]

cheers will have a look at the fire service manual should be able to grab a copy off ebay

[Big T]

The Swedes have adopted shooting cylinders

Firearms
The use of firearms in the rescue service is relatively new in Sweden. Shooting at hazardous gas cylinders is, for example, one method of quickly preventing the danger of explosion, which has become popular within the rescue services. Shooting a gas cylinder in connection with or after a fire is an excellent method of minimizing the effort and making a hazardous area safe. Shooting is however, not the only, but just to have one of several methods that can be used to defuse the threat of an uncontrolled explosion. In order to shoot a gas cylinder you have properly equipped and trained personnel, suitable weapons and sights, as well as special ammunition. In other words, you need a powerful ammunition that has the ability to penetrate the gascontainer and make as large a hole as possible. You therefore need large calibre ammunition, fuII metal jacketed as well as tracer and/or armor piercing ammunition.

[messy]

Before you can shoot it, you have got to be able to see the cylinder from 200m+

Not always easy when it's in a damaged and perhaps parially collapsed car workshop or hidden deep within a building site!