Another propane question

[stuwaudby]

All, I have been working in the gas industry for over 20 years now, I used to be a gas process engineer at one of the largest processing plants in the UK and was responsible for much of the safety. Let me straighten out a few facts and point out a few of the risks of storing a propane bottle indoors. You can then decide how willing you are to take those risks and consider the consequences. Please bear in mind that the main fire risk in your house is not your torch or gas bottle, a fire is much more likely to be caused by electrical fault or equipment. The presence bottle in your house does however dramatically change the consequences of a fire. I am sorry if you find any of the following upsetting.

1. Propane does sink, briefly. It is heavier than air but will rapidly diffuse as it warms to ambient temperature.

2. Virtually every mains powered electrical appliance in your house is a source of gas ignition. (They are also potential sources of fire without gas present). Do you turn off everything you can before going to bed?

3. Every propane bottle is different, every one has had multiple previous keepers and could have suffered abuse. All are adequate and tested to hold the gas safely under normal circumstances. In a fire some may survive intact, some may not.

4. Two types of explosion can be caused by gas bottles:

a. The most common is where gas enters a property, mixes with the air and then ignites. The explosion is serious enough to blow an external wall down but will probably not kill you directly. Flying bricks and debris could. The resultant fire, smoke and lack of oxygen probably will kill you.

b. The less likely but much more serious explosion is caused by the bottle itself and is called a BLEVE. Heat on the bottle causes the liquid propane to boil and the pressure in the bottle increases dramatically. The heat also weakens the steel the bottle is made of. When the bottle eventually splits a cloud of propane is instantaneously ejected and mixed with the surrounding air. Almost instantaneously this ignites causing a concussive explosion. A 13 kilo bottle could easily flatten your house and cause structural damage to the neighbors. Calor gas bottles are designed so that the valve mechanism insert is weaker than the bottle, this should mean that the top of the bottle should blow off before the pressure reaches a point where the explosion will very serious. You still get a high pressure jet of propane shooting through your house. Watch the following videos, some of them are of real gas bottles blowing.

http://en.wikipedia.org/wiki/BLEVE
http://www.youtube.com/watch?v=S3PgwSGWvkw
http://www.youtube.com/watch?v=LvThP6zdfMw
http://video.google.com/videoplay?docid=1505191406742106917#
This last one explains how it happens:
http://www.youtube.com/watch?v=sl-JgyQA7u0

The US "daisy cutter" fuel-air bomb uses the same principle.

5. If there is a propane bottle inside your house the fire brigade will only enter your house to save life. After saving life, their first priority will be to cool the bottle, even if it means the rest of your house is left to burn down.

6. Domestic gas regulators contain a mechanism to restrict gas flow in the event of a pipe break. The welding regulator used for glass torches may not.

7. Calor gas guidelines do not allow propane to be stored indoors. (Butane can be because it has a much lower pressure and poses a lower risk.)
http://www.calor.co.uk/customer-services/lpg-safety/lpg-cylinder-storage/cylinder-storage-information/
http://www.calor.co.uk/customer-services/lpg-safety/lpg-cylinder-storage/full-and-empty-cylinders/
http://www.calor.co.uk/documents/43/original/code-of-guidance-for-storage-of-cylinders.pdf

8. Just because your house hasn't burnt down and your gas bottle has caused a problem in the last 20 years doesn't mean it wont happen tonight.

Other things you should consider when making your mind up are:

Is your house detached?
If your house is a terrace does it have common loft space?
What type of wall separates your property from the neighbors.
How many babies are in the property, are there enough adults to get them out without return trips.
How many children are in the property.
How many babies and children are in the adjacent properties?
What are your fire escape routes?
Are your bedroom windows locked? Can you get out the window? Will you break bones if you jump?
Does your family know exactly what to do in the event of a fire? Do they know the escape routes? Do you have a plan? Have you ever practiced?
Do you have to pass near the gas cylinder to escape?
Do you have smoke alarms?
Is the smoke alarm positioned along your escape route?
Do you have a fire extinguisher? Is it located near an exit?
Do you leave electrical equipment on over night?
When was your house last re-wired?
When were your electrics last inspected?
Can the fire brigade get a water hose onto your gas bottle from outside the house if there is a fire?
Would you expect a fireman to enter a burning house containing a gas bottle to save the life of your family?

In 2005 there were 57,400 house fires in the UK, 487 people died.

Personally I used to store my bottle outside and bring it into the conservatory only when in use. I have now drilled a hole through the wall and leave the bottle outside. The regulator is protected from rain by a bucket.

P.S. Is your rubber gas hose located in a position where hot glass could fall onto it?

[Soozintheshed]

Wow, that made fascinating reading, thanks for sharing.

[madpup]

stuwaudby that is very insightfull and i think your statement should be made a sticky in the faq
thank you for sharing that, i will now be storing outside.

kind regards.

[Dickie]

If nothing else it should added to the Wiki !

Thanks stuwaudby

[julieHB]

Very informative and sobering - gulp! Thanks for taking the time to type that up, Gasman 

[stuwaudby]

I'm very glad you find it informative, I would be happy to tidy up to FAQ quality.

Must now remember to find time to do it....

[Pat from Canvey]

And how many of you are going to stop driving your cars IN CASE THERE IS AN ACCIDENT. We all take risks every day but weigh up the risks versus the benefits. Having survived a serious car crash 20 years ago due to another  driver's stupidity, I know how easy it is to be killed by an unforseen event but we take the precautions we think are necessary. If we stopped doing anything where there is a risk, our lives would be unbearable. I take care with my propane bottle as I do in my everyday life but will still continue to keep it inside. A couple of years ago at the age of 60+ I travelled on a zip line over a gorge in NZ, a great experience. Should I have desisted in case I fell?

[Dickie]

But Pat, we are not talking about STOPPING doing something, just reducing the risk while doing it.

Surely it's best to reduce the risks in any given circumstance. By your argument we might as well all not bother with any safety precautions whatsoever. I'm sure you wear a seat belt while driving... because it's reducing the risk of you dying IF you have an accident.

In this example we are reducing the risk IF we have a fire, or IF the canister leaks.

With regard to the zip wire, would you have done it if the operator had told you that he hadn't bothered checking the harness, and the wire might be a bit worn, but "don't worry we all take risks".

I'm sorry, but there are some things that are worth doing... and as simple as this is... for me at least, this is one of them.

[sparrow]

Thanks stuwaudby, great reading. Lots of things for my 'good practice' list (and a few happy nods for stuff I already do *nods happily*) - always good to have clear input and advice from experts 

[♥♥Tan♥♥]

I think this is great info and should definitely be added to the wiki, its up to the individual to choose how they do things but at least they will have all the information to do it.

Thankyou so much for taking the time Stu