Do You Turn Your Gas Bottle Off

[Derek Uzzell]

Enodreven: 1. Returning to your original question, I believe there are no general national or international traffic-related regulations (or insurance requirements) that compel a motorcaravanner to turn off his/her motorhome's 'domestic' LPG supply before the vehicle is driven. However, the risks involved in driving with a turned on LPG bottle (or tank) are clearly higher than with the bottle/tank turned off and it would be deliberately perverse to argue otherwise. 2. About 5 years ago I asked Truma(Germany) what was the legal position on using an LPG-fuelled heater in a vehicle being driven on European roads. I was told that some countries (like Germany) had laws that permitted it, while most (including the UK) had no general regulations about the practice. Only France and Denmark specifically forbade using a gas heater en route. I was given the legal references involved but I no longer have the details. If you ask Truma(Germany) nicely I'm sure they will supply you with the information you want. 3. According to Truma's brochure, their "Drive-Safe" system allows compliance with 2006-introduced EU regulations relating to on-road use of LPG-fuelled heaters. Apparently vehicles fitted with this system can legally have gas heaters running while driving even in France. I described Drive-Safe (called "SecuMotion" in France) on this forum last year, but it needs highlighting that it only provides a certain degree of gas-leak protection. Drive-Safe has 2 components - a 'leak-sensing' regulator, plus a 'leak-sensing' high-pressure gas hose. However, both components operate on a catastrophic leak basis and won't protect against 'below the cut-off threshold' leakages that might develop while driving or as the result of an accident. 4. Germany has a motorcaravanning culture where while-travelling gas heating is the norm, so the Germans won't be turning off gas bottles before driving their motorhomes. I've never seen a French camping-cariste visit the gas locker when stopping or before driving off, so it's a fair bet most French don't do it. Bill Ord mentions AES-type fridges earlier, that actively encourage the user to leave the gas supply permanently on. These appliances are becoming increasingly common even in 'budget' motorhomes. All this leads me to suspect that the gas bottle on/off ritual is mainly a UK habit and (as your straw-poll suggests) one that not too many UK motorcaravanners religiously follow. If you want to add me to your statistics, you'll need to put me in the "I Normally Leave The Gas ON" column. The reason for this choice is similar to Bill Ord's - it's more convenient when you move around a lot. I don't defend my actions and I fully recognise the risks inherent in the practice. If you ask me "Must I turn off my motorhome's gas bottle before setting off?" I shall tell you No. If you ask me "Should I turn off my motorhome's gas bottle before setting off?" I shall tell you Yes.

[Mel E]

This to Brian (enodreven): I think Brian K and Derek have just about said it all. Apologies if I didn't say get everyone clear and call emergency services (it did seem a bit obvious!) and if I used a colloquial form (asbestos blanket) but I think everyone except you understood what I meant. As for Fire Brigade advice, yes I am aware. The problem is this: 1. Either the fire is on the high pressure side close to the cylinder in which case you will almost certainly be unable to turn the gas off and should get as far away as possible before the cylinder blows up. 2. Or it is on the low pressure side, in which case, 99% of the time you will get a 6 to 8 inch yellow flame (just like a Bunsen burner with the air inlet shut off) of pure, unoxygenated gas burning, leaking from a loose connection. In most cases, it will be possible to turn the cylinder off and solve the problem. In the minority of cases where this is not possible, you make a judgement: - can you put out the flames safely and prevent the whole 'van burning to the point where the cylinder also blows up? (There's no point in doing so if this doesn't enable you to get to the cylinder to turn the gas off.) - or can you not? in which case you hope the emergency services arrive in time. There have been two recent cases where major motorways (M11 a couple of weeks back) were closed for 24 hours because of hot gas cylinders after vehicle fires. I return to your original post, Brian (enodreven), in which you asked for 'help and advice' about turning gas off. You've had it - turn it off and none of the above is a danger during travel except in a crash affecting the main cylinder. Your pseudonym seems appropriate - 'never done' backwards. Let's let this one die gently now, please!

[Brian Kirby]

There is a further point in connection with the AES fridges.  They have a time delay that prevents selection of gas when the engine is stopped for, I believe, 15 mins.  This is, I understand, designed to prevent the fridge firing up on gas while on a filling station forecourt.  The risk, again I understand, is ingestion of a petrol/air mix following a fuel spill on the forecourt. 

Much the same reasoning applies to naked flames, cigarettes etc on forecourts.  Most people seem to accept and adhere to this convention.  I don't know if this convention is UK specific, but it does seem to be widely observed outside UK as well. 

Similarly, I don't know whether the Dometic AES gas selection delay is UK specific, but I gain the impression that it, too, is in more widespread use.

The truma heaters, on the other hand (so far as I am aware/can discover), have no such interlock with the engine so, presumably, can fire up at any time including while the vehicle is being re-fuelled.  This seems odd, since the Truma Combis have fan assisted flues that would suck any petrol fumes through the heater. 

May be Truma has proved that firing one of their heaters in a petrol fume rich atmosphere doesn't result in a fire in the heater ducts or beyond.  May be someone has carried out a risk assessment, and reasoned that the coincidences necessary for the event to arise are too remote to warrant additional controls.  However, I'll definitely be leaving it to someone else to prove how real the risk is!  In the meantime, compared to Dometic's approach, there seems to be quite an anomoly.

On the Truma Drive-safe/SecuMotion apparatus, I believe this is only available to manufacturers at present and Truma haven't clarified when, if ever, it will be available for after market fitting.  It has the limitation Derek outlines, in that it will not (at lease at present) shut off the gas where the rate of loss is at, or below, the rate of consumption of the installed equipment: fridge, cooker, heater etc.  Thus, quite a healty leak could progress unchecked.

In reality, a properly fitted and maintained gas installation should not develop leaks, and the number of instances of fires resulting from this cause are, I suspect, very small.  In the final analysis, Mel B's fire resulted from someone eles's incompetence, not the normal stresses and vibrations of use. 

The greater risk, I suspect, is a road accident, which also adds the risks of fuel spillage and heat sources to the mix.  A ruptured high pressure hose, with the cylinder cock turned on, will spectacularly evacuate the contents of the cylinder.  It will not of itself cause a fire, but spilled petrol from other vehicles spreads readily, and hot engines/exhausts, sparking batterys and other ingition sources are not uncommon post accident.  Adding leaking gas can only make matters worse, and is so easily avoided by turning the cock off.

My further concern is the design of the cylinders that we use.  There is a perverse advantage, if the cylinder is involved in a fire, in allowing the gas to escape, even if this makes the fire worse.  Gas cylinders cannot survive the pressure rise that occurs when they are heated in a fire, and burst. 

I witnessed a fire in a builder's yard where the gas cylinders became involved.  I was on the tenth floor of an adjoining office block and yes, I should have been working.  But hey, a grandstand view!! 

The fire brigade had difficulty getting to the cylinders, located behind the centre of the fire at the end of the longish, narrow yard.  Thus, the fire got there first.  The bursting cylinders were projected upwards like rockets, rising way beyond our tenth floor window.  Then, of course, they descended with equal velocity!  Faced with this, the fire brigade had to withdraw and let the fire burn out, the town centre, surrounding roads and adjacent railway stetion were all closed for about four hours.  Chaos on a grand scale! 

However, if those cylinders had had a pressure release valve, they would have gassed off into the fire, causing periodic great lugs of flame, but wouldn't have burst. 

So, valves closed prevents fuelling the fire if it occurs, but it does cause quite an additional safety risk to the emergency services if/when the cylinder/s burst.  No win? 

Notwithstanding, I'm still firmly in the shut them off camp.

Regards

[enodreven]

Hi, Just a couple of points "Quote" Your pseudonym seems appropriate - 'never done' backwards. I do hope you arn't suggesting by refering to my pseudonym that i don't turn the gas off, if you are i would suggest you read all of my posts and you will see i clearly state:- "Oh and by the way i do turn my gas off??" Oh and by the way the name is of my Narrowboat Quote Let's let this one die gently now, please Why, there are a lot of very informative and constructive comments still being made, if you don't want to join in or read them then please feel free but others may feel differently ? so please don't try to stifel these posts And while i won't comment directly on your statement regarding the size and type of flame that one can expect from the low pressure side of the gas regulator, I would say that having been in the gas industry all of my working life i have never tried to find out what size and type of flame that could be expected from the open end at the various regulator pressures upto 50mb as i have felt that to do this would be quite dangerous, and i would also suggest that no matter what the size and type of flame that would be produced mine and others comemnts still stand, don't be a hero ?? As for the stopages on the motorways i think they were regarding bottles that were turned OFF, as Brian has explained in his post ? So please don't stop posting there is a lot to learn ? Thanks everyone, and never make assumptions always ask ?? first

[Brian Kirby]

Has anyone else noticed that you can turn on/off the e-mail notifications thread by thread?

Go to the main "Motorhome Matters" notice board and open the thread from there.  Scroll to the bottom of the page and click on the link entitled "toggle e-mail notifications".

Check/uncheck the box as desired, and only the notifications on that particular thread will be affected.  Your general option to be notified or otherwise on other threads will remain unaltered.

Neat, or what?

[Yorkshire Tyke]

Hi endroveN See you are one who tests the water then asks if it is warm enough to get in Never worked in the gas industry; I was brought up in the chemiacal industry and worked mainly in production of petroleum products and explosives, where we used gas, electricity and water A GOOD combination dont you think

[Mel B]

I can't put a copy of the report on the web as we only got it verbally from the chap who had done it, who rang us to give us it as a courtesy but as the dealer had paid for the report it went to them. If we really wanted I'm sure we could get a copy but there's no point. The leak was due to someone's incompetence but the pipe look okay beforehand, somehow it had passed a gas test 2 months earlier but had been installed wrongly from the very beginning. The pipe only came apart after we'd been driving around so although it's actual detachment was due to a faulty installation, the driving around had made it come apart so how you can tell if the normal driving around would or would not cause this on a 'not so faulty' pipe I don't know. So, how can you tell if your pipe joints are safe? You can't unless you undo all of them, and re-seal them, and even then you can't get to them all so you've no way of knowing if you've got faulty/bad joints or not. The cupboard where the gas pipe is located is under the hob at the opposite side of the van from the gas locker and the flame was 5ft high - my husband isn't a fisherman and this is not an exaggeration, it really was that high and as fierce as a blow torch. I've posted a few photos at the following address for those of you who want a look, there are quite a few more but I don't want to overload the page for those that don't have broadband (just cut and paste into your browser): http://www.micromaniacsclub.co.uk/frames/Mel's%20web%20page.htm Quite apart from the damage to the van which the photos don't really do justice to, it really shook us up - you may think you'd cope in this sort of situation but we were nervous wrecks afterwards! Thank goodness it was on the penultimate day of our holiday. Piggy (the dog) survived thank goodness, despite being absolutely terrified but she was a tough little madam, eventually all her singed whiskers and eyebrows fell out. Unfortunately though we had to have her put down last week due to her heart failing - 16 years and 4 months, extremely sad but not a bad innings for a touch little cookie who had some lovely holidays in the motorhome. Whether you leave your gas turned on or not, enjoy your 'vans and keep yourselves safe.

[Jack Kelly32]

That report is a certain lesson for us all, I will ensure that my gas is turned off in future

[Terrytraveller]

Hi Mel, Sorry to hear of your problem. I have just remade some of the compression joints on 8mm pipes, the olive on the old joint I couldn't budge, the brass olive had just about ammalgamated with the copper pipe, so even without support to the pipework, I wouldn't expect it to come apart. To test the strength of the joint, support one side of the pipe with your hand and pull as hard as you can in a straight line of force the other side of the pipe, with your other hand, the pipework in joint will not move even slightly, if it moves it is not secure. One of the questions you have asked, how do you know your pipework is gas tight after your journey? How about one of those gaslow pressure gauges as gaslow pt no 01-4330, you can buy them for different types of cylinders and gas types. The Gaslow system I have just installed has one gauge for each cylinder. Before I turn on the gas I look at the gauge when first opening the gas locker door, if the colour is green I know that all the gas joints are secure after my journey. To test how fast a leak is detected by these gauges, turn the gas on then off on the cylinder to pressurise the system, note that in a gas tight system the gauge colour will be green, push any gas control inside the camper as if to light the appliance, check the gauge and you find it either Red or Yellow, showing you have lost gas pressure. I have found that once pressurised, my gas system pressure gauge is showing green after a week of not using the camper, indicating that I have not lost any gas at all from the camper pipework, this is with all manifolds to all appliances open. Of course if you were one of these campers that never turns off the gas when travelling, I have heard they are a dying breed, then I suppose you have to wait for some sort of explosion or fire to indicate a problem!! Mel that's not a dig at you. If any reader has one of those systems that shut off the gas in the event of a collision, then how do you check for a small gas leak at any time whilst away using the camper, I suppose trust to luck and the nose as I have done over the last forty years or so!! Regards Terry

[Mel B]

Hi Terry Thanks for your comments, we were fortunate in that we didn't travel with the gas on so the 'problem' only occured when we were stationary and had just turned the gas on to make a cuppa. If we'd been daft enough to have had the gas turned on and be travelling when it happened, well ........ you can see why I'm so keep to tell people NEVER to travel with gas on.