Club 80-90 Forums

Thinking of installing a gas alarm in the van. Not sure which type it is that I need though. I don't have a gas fridge, just a gas cooker. I know you can get carbon monoxide alarms, but these wouldn't tell you if you had a gas leak would they? Is there an alarm which can do both?

what have you guys got fitted to yours, and how is it fitted? Battery power, or wired up to leisure battery?

thanks,
kathy

thanks matt, must have missed this!

anyone got one of these? this should do the job i'm thinking?....

its a bit confusing.. natural gas alarms to be fitted high up, lpg lower down. this says its right for lpg butane, propane... is that a natural gas or not? just want to make sure i get the right kind of alarm.....
advice appreciated!

kathy

anyone know if the alarm above is alright for my camper?
i'm rubbish at gas things....

it looks good to me. These are for detecting leaks from your bottle or gas pipework - depending where you mount it.

LPG is a family of petrol based gases including propane and butane so is ideal for your gas bottle & cooker. LPG is heavier than air so falls (through your drop out hole ) and the sensor needs mounting low. What they say about mounting the control unit high is good. I have a Lidls alarm that I haven't yet fitted as its "all in one" so I have to get wiring into the gas locker.

The other gas to be aware of is the CO2 from gas that hasn't burnt correctly. This is lighter than air so would need monitoring high up. Providing you cook with adequate ventilation and don't try to warm yourself up by lighting a ring these are not so necessary.

thanks dave!

i've been doign some more reading around this, and come accross the following:-

'Gas alarms should detect LPG before the concentration reaches 25% of LEL. To put that in perspective, a normal nose will detect a very strong smell of gas when the concentration is about 5% of LEL, that's before most of the alarms will be triggered. '

so from that i gather you would know before the alarm was triggered.... mmm... so who has one of these alarms fitted?

also, has anyone got battery operated carbon monoxide alarms like smoke alarms have?
kathy

It is interesting that the detector doesn't give figures so maybe 25% LEL is where it works. (I had to look up LEL even though I use it on drawings almost daily = Lower Exlosive Limit.)

Two things to consider. Escaping LPG can explode which you don't want. But as you have already discovered you should smell it before it reaches a very dangerous level. Equally important is that you can suffocate. I think (I got this bit wrong in the past) LPG displaces the air so you don't die from the gas but die from having no air. Anyway, the detector should alert you before you get there. Don't forget that 25% LEL is NOT 25% of the available air, it is probably a much lower concentration than that. If you ALWAYS turn your gas off at the bottle when not cooking then you don't need a detector. If you sometimes/never turn it off, for £20 you get an extra peace of mind. Don't forget that it can leak while you're asleep.

A CO detector could well become the next vitl fitment - those kids who died on holiday recently could have been saved by one.

edited to correct gas type

Very true Dave,
Will be getting a Carbon Monoxide alarm for sure! you can get those battery operated too, which is good. Don't want too many htings attached to my leisure battery.
I turn off my gas all time when not in use, so i'm thinking i might leave the gas leak alarm for now. As long as there is a hole in the floor it should be fine i suppose.

with all of these things you should do a failure mode analysis or risk assessment. What is the chance of something going wrong. What would be the consequence if it happened?

Anything to do with gas scores high on the consequence front so you need to reduce the risk of anything happening.

You are only using the gas to cook and turn it off immediately so your chances of an undetected leak is small. If you have a drop out hole then the risk of a gas build up is almost neglible. Therefore a leak detector isn't going to give you very much extra protection.

The next problem is CO and again, the fact you are only cooking while awake ( ) reduces the risk of suffocation. However that's not a reason to forget about the dangers. I don't think a gas cooker in a well ventilated room should produce enough CO to set an alarm off but you may have forgotten to open the window or the gas/air mix has changed (blocked jet?) resulting in excess CO. In other words probably worth fitting.

I know somebody with one that detected the burnt fridge gas blowing back into the van (probably gas trapped by the awning and then comming through an open window) in the summer. Without the alarm - who knows!

Having typed all that I have to admit to not having either a CO or a smoke detector. I really MUST add them this winter.

Incidentally, I have had a look at LPG concentration levels. The LEL for LPG is 2,5% gas / 97,5% air. Therefore a detector working at 25% LEL is detecting 0,00625% gas in air, or 6000 parts per million! That's pretty good even if it is 5 times worse than your nose.


edited to change CO2 to CO

dbroada wrote: Two things to consider. Escaping LPG can explode which you don't want. But as you have already discovered you should smell it before it reaches a very dangerous level. Equally important is that you can suffocate. If you ALWAYS turn your gas off at the bottle when not cooking then you don't need a detector. If you sometimes/never turn it off, for £20 you get an extra peace of mind. Don't forget that it can leak while you're asleep.

A CO2 detector could well become the next vitl fitment - those kids who died on holiday recently could have been saved by one.

dbroada, thanks for all the info on lpg & gas alarms. I think that most people are worried about having the gas turned on in their camper during the night. It's ok being able to smell a particular gas during waking hours but during the night most people would just be poisoned or asphyxiated in their sleep depending on the gas.

I spoke to Kathy yesterday prior to her posting the question about gas alarms & the original point of concern was the use of Propex/Hot Box LPG heaters during the night ie. How safe are they? I think that there is a gas alarm that detects LPG/CO/CO2/Noxious Gases. Noxious gases being the ones sprayed into campers at night by thieves. I think that these all round detector are about £65.

Lastly, the tragic death of the two children in Corfu was caused by Carbon Monoxide poisoning, they wern't asphyxiated by Carbon Dioxide.

Bowton Lad wrote:[Lastly, the tragic death of the two children in Corfu was caused by Carbon Monoxide poisoning, they wern't asphyxiated by Carbon Dioxide.

My appologies. Pure stupidity on my part and CO is the one you should be checking for.

Although I work on gas detections systems for oil rigs I don't have any real expertes in this subject. I have just absorbed the information from around me. In other words don't blame me.

The 2 areas of note are combustible gas (heavier than air) and toxic (lighter than air). As such no one detector could be placed for the best result although it could be done with remote sensors. (That is after all how its done in the North Sea). Whether it is better to have one multi purpose alarm or 2 dedicated alarms I couldn't say. If (say) the CO monitor failed in a multi purpose or the CO individual detector failed you would be in the same position. The LPG detector wouldn't (necessarily) detect the CO.

How safe are Propex etc? Judging by how many are installed, I would say safe enough. The exhaust gas should be sealed from the van (as should the fridge flue but I know mine isn't) which takes the CO away from the living area. The same safety route of drop out holes is appropriate to all gas fired items.

Noxious gasses are possibly a different thing all together. I am still in the suspisious stage of wondering why there are many reports of gassing but none (to my knowledge) of fatalities. Considering how difficult it is for a trained anethestis to get it right I find it amazing that croocks can do it so easily. I thing tierdness and the local brew has a bigger part to play than is being reported.

As for the price of safety. I haven't got anything installed but really must. £65 is very little to pay. And if you have children, £65 is a nothing.

My Westy has the heater positioned on the outside of the vehicle, underneath where it`s a lot less likely to do you any harm. The combustion gases and the blown air don`t come into contact with each other directly, so unless there is a fault where it allows them to mix (internal pipe breaks or similar?) then it should be reliable and safe. IMHO I personally don`t think it`s a good idea to have the heater mounted inside the vehicle under the seat-box.

Afternoon spent on Google!

an american article about houses but some bits are relevant...

http://www.edisonnj.org/fire/articles/monoxide.asp