Condemned Gas Cooker

[shellards]

I bought a 2nd hand caravan dating from about 1992, last April. I have used it a couple of times over the summer and had no problems. On taking it for service in December, amongst other problems identified, the butane gas installation was identified as faulty. In particular, a flame had apparently shot out of the side of the cooker when it was lit. I had to sign a disclaimer to take the van away without having this problem repaired.

I have done quite a bit of DIY plumbing and have indeed installed the cooker in my house which runs on bottled propane gas. I nevertheless take the safety warnings concerning work on gas appliances seriously and would like a view on what might be the problem in this case and what work it might be appropriate for me to undertake myself.

I have taken the hob out for a closer look and have noted some corrosion in the pipe work. [url=http://nethercarruchan.myphotoalbum.com/view_album.php?set_albumName=album02]
Here is a link to some pictures which may assist in diagnosis.[/url]

[htg engineer]

The caravan should be re-piped and new gas appliances fitted (where necessary) by a CORGI registered installer, competent to work on LPG.

Really not a DIY job.

[shellards]

I have thought about this answer for several weeks now but conclude that I am not satisfied with it. I would like respectfully therefore to ask for some explanation of the issues which make this "not really a DIYjob".

Of course where one is intending to hire or sell a caravan, then not to use a Corgi approved operative would leave one liable for any subsequent disaster which might occur. In these circumstances I would without question have the system Corgi checked.

In this case, the liability is entirely mine. Of course I also wish to ensure safety for myself and my wife (and dog).

What are the issues which lead to a system becoming dangerous? Let me hazard my own explanation, based purely on a common sense understanding of the issues.


I assume that where there are gas leaks and the gas is switched off and left for a period of time, there may be ingress of air into the pipes resulting in an explosive mixture developing in the pipes. Thus where there is a suspected leak, pipes should be purged of air before any attempt is made to light a fire or gas ring.

Gas leaks, where there is pressure in the system, clearly may lead to an explosive mixture developing in the room space where the appliance is situated. A spark within a light switch could detonate this mixture. Result: total obliteration. However, bottled gas contains additivies which make it detectable by smell. Thus, if there is a leak on a scale where an explosive mixture were likely to develop, it would be noticable. Tiny leeks on the other hand will disperse naturally and be neither noticed or dangerous.

Perhaps this is dangerous nonsense. If anyone can offer me an intelligibel explanation of the error in my understanding then I would greatly appreciate it.

[htg engineer]

Carrying out any gas work without being CORGI registered is illegal - Fact.

If I was to re-pipe a caravan, the installation would be illegal as I do not have LPG qualifications. So why do you think a DIY installation would be ok ?

Natural gas also has a smell added to it - so that should mean it would be noticed too - resulting in no gas explosions- ever - but there are still gas explosions.

LPG is heavier than air, natural gas is lighter. Small natural gas leaks will disperse and disappear un-noticed. LPG gas gathers at ground level - and will spread along the ground creating a fire/explosion hazard.

Hope this helps

[roger196]

[b]Htg Engineer[/b]
On a number of occasions, you have claimed diy gas work is illegal. Searching through the statutory instrument, I can only find that it is illegal for employees or self-employed to carry out gas work as part of their business. I would be grateful if you would direct me to the relevant paragraph of the relevant statutory instrument which supports your view.
I strongly agree that people who are not competent should not touch the gas side of a boiler.
[b]Moderator[/b]
You may prefer that this exchange of views is not posted but dealt with direct.

[htg engineer]

To work on gas you have to be deemed competent by CORGI. The only way to be deemed as competent to carry out gas installation work - is to sit a CORGI approved examination.

If you installed your own boiler, and then paid a CORGI registered installer to service/repair the boiler, and the boiler had not been fitted safely and according to Gas Installation and Use Regulations - this would be reportable to CORGI and if a dangerous situation which could cause risk to property or life then it would be RIDDOR reportable.

If you carry out DIY gas work, then you have to be available to sit a CORGI approved examination if/when required. If you have been carrying out DIY gas work CORGI would expect you to pass the examinations and be deemed competent. If you are deemed incompetent then you have installed gas appliances, pipework illegally.

CORGI examinations have to be re-taken every 5 years. CORGI require a 100% correct pass rate in each exam - and believe me it's not easy. They will fail you and I've known gas installers with many years experience that have failed. I'm sitting mine again next year - and i'm not looking forward to it.

Let me point out that in the following HSE statements, gas installer doesn't mean a trained gas installer - it means ANYONE that installs gas appliances or pipework.

HSE:
'It is against the law for a non-registered installer to do any work on gas appliances and/or flues. Phone your local HSE area office or CORGI'

'Using a gas installer who is not registered with CORGI is not only illegal but can be dangerous, as there is no guarantee of the installer’s competence. CORGI - registered installers have been trained in gas safety and the standards needed for appliances and installations. CORGI work hard to improve standards in industry and help to train and educate their registered installers so you can be sure that any work completed by a CORGI - registered installer will be done competently and safely. ALL CORGI registered installers must carry a CORGI ID card. Always ask to see the CORGI ID card before any installer begins work on your gas appliances'

If I left a dangerous appliance and people were killed, i'm responsible not my employer. It is classed and corporate manslaughter and i would end up in prison. A DIY gas installer would get the same - if not a longer sentence.

[roger196]

You might find it useful to read the relevant part of the Gas Safety Regulations ( Installation and Use) SI 2451 of 1998. I set out the relevant paragraphs below.
Qualification and supervision
3. - (1) No person shall carry out any work in relation to a gas fitting or gas storage vessel unless he is competent to do so.

(3) Without prejudice to the generality of paragraphs (1) and (2) above and subject to paragraph (4) below, no employer shall allow any of his employees to carry out any work in relation to a gas fitting or service pipework and no self-employed person shall carry out any such work, unless the employer or self-employed person, as the case may be, is a member of a class of persons approved for the time being by the Health and Safety Executive for the purposes of this paragraph.

There is no mention of Corgi in para3(1) and thus they clearly have no jurisdiction in this area. Corgi only comes into play for employees and self-employed in para3(3). A diy'er does not fall into the category of employee or self-employed.

[htg engineer]

EXACTLY

IS competent - not thinks he is.

[htg engineer]

Gas Safety Regulations ( Installation and Use) SI 2451 of 1998. I set out the relevant paragraphs below.
Qualification and supervision
3. - (1) No person shall carry out any work in relation to a gas fitting or gas storage vessel unless he is competent to do so.

EXACTLY

IS competent - not thinks he is. In the trade - Competent means approved by CORGI by sitting examinations.

I take it you're not CORGI registered.

OK the HSE and CORGI advise strongly against DIY gas work - Most people understand the seriousness and consequences of dangerous gas installations - but you still get idiots in and out of the plumbing trade thinking they can carry out DIY gas work then hopes and thinks it'll be ok. If it was as easy as DIYers think it is why do we re-sit exams every 5 years. Putting lives at risk (their families) to save a few quid.

[roger196]

I think we need to be careful to distinguish between who is carrying on a trade and who is not.
A plumber who carries out gas work does so as part of his trade and thus needs to be registered with Corgi.
A diyer is NOT carrying on a trade and therefore is not obliged to register with Corgi. His work is perfectly legal providing it is competent. Nowhere in the statutory instrument can I find that Corgi has the legal authority to determine whether a non-trader is competent or not. If you disagree on this point, you will no doubt direct me to the relevant paragraph.
The borderline between trader and non-trader is often difficult to determine. Think of a person who sells one car per year, clearly not trading. If he sells ten cars per year, clearly is trading. Somewhere in between is the boundary.
No other trade/profession requires their members to requalify every five years. Think of surgeons who kill many more people per year than are killed by gas fitters. The need to requalify every five years is more to make money for the trainers than quality control.

[Oliver_murphy]

This is my observation on 1. the law, and 2. this discussion.

You only have to be CORGI registered to work for financial gain or reward. This is what CORGI say on there own website.

However, you have to be competant to work on gas.
Currently, the only people who can deem you competant to work on gas, is CORGI. In the same way only the DVLA can deem you competant to drive.

This means that to work on gas, you have to sit a CORGI recognised exam, (ACS). ONly when you have passed these can you touch gas - DIY, because only then are you deemed competant.

To then work for money, in your own business, or for a friend or anything that involves reward or money, you then have to become registered with corgi.

Example from another "trade"

You have a full UK driving license. You have held it for 15 years, and think you are competant at driving. You can take your friends to the pub, drive to Wales, whatever you like.
Can you work as a taxi, earning money?? NO You have to get a taxi license from the local council.
This is fact, as is the gas. It is not open to interpretation, its the law, and is punishable in court.

[Oliver_murphy]

[quote="shellards"]
Gas leaks, where there is pressure in the system, clearly may lead to an explosive mixture developing in the room space where the appliance is situated. A spark within a light switch could detonate this mixture. Result: total obliteration. However, bottled gas contains additivies which make it detectable by smell. Thus, if there is a leak on a scale where an explosive mixture were likely to develop, it would be noticable. Tiny leeks on the other hand will disperse naturally and be neither noticed or dangerous.
[quote]

The explosive range of LPG in AIR is just 1.8% to 9.5%. this is very small, and would be indetecable as LPG would sink to the floor, and unles you sniff your carpet everytime you walk into your van, you would have no idea if it was explosive or not.