I'm off on a nice 12 day trip from London to the Peak District, Lake District, West Coast of Scotland and the Cairngorms and back in a couple weeks. I'm gonna have a 7kg butane cylinder, but not too keen on having it inside the car. I don't have a roof rack, but was wondering if anyone knows of a tow bar or spare tyre bracket that is on the market. Appreciate any ideas.

whats wrong with just putting it in the car?

Can I assume that you have mains gas piped into your house which will be isolated by automatic valves? Then a single manual valve isolation should not worry you.
All LPG is stenched so if it leaks it stinks and so can be detected. So if your gas bottle doesn't stink, it will be fine.

Yes there is a tow bar attachment - most of us know it as a Trailer!

Well was more keen on saving the space for other things. Travelled many times with one, so is more about the space.

Borrow a trailer.

I think you should have a sticker on your car to warn emergency services of the presence of a gas bottle if carrying it in a car.

Thanks. I'll get the sticker. Don't want a trailer. No need! Maybe once I've got some toys!

The first two paragraphs are taken from the RAC forum.

If LPG cylinders are being used for private use, camping/caravaning, then no regulations apply, including stickers and warning signs, unless you are carrying more than 333kg. If they are being carried during the course of your work then it's the responsibility of your boss, his DGSA and the consignor to ensure that the relevant regulations are complied with.

If your going through the Channel Tunnel or any road tunnel then you'd possibly need to ask their advice on what is permitted.

A gas cylinder which is fitted on or in a caravan or motorhome comes under different regulations and generally a "gas bottle" sticker is affixed to the door or lid of the gas bottle housing, but that might be more to do with informing the owner on where and how to place the gas supply than making any kind of safety warning to the emergency services.

Whilst looking for some information, I did read on the BOC website that while being transported gas cylinders should not protrude beyond the sides or ends of a vehicle, but I presume that would apply to the larger lorry type transport. Having said that, mounting a gas bottle on some sort of carrier on the towbar could well constitute a hazard, such somebody be unfortunate enough to run into the back of you.

I do know that there are different regs regarding the storage of red (propane) and blue (butane) cylinders.

Compressed air and medical gases are usually identified with a sticker on the access point, such as the boot lid.

I must point out that I am in no way qualified (DGSA/ADR/CDG 2007) to give advice on carriage of dangerous goods by road.

what I see by having them attached to the rear of vehicle is a safety hazard to you and others. Some one does a rear ender to you and there is a tank leak, a very good chance for fire feed by pressurized gas

Thanks. I did think about that. Well, will keep in the back, should be fine.

No different to having 100lt LPG tank in the back, except that they will have venting to outside the cabin, while yours wont.

There's nothing special or dangerous about carrying it, but we used to wrap ours in a white bin liner to keep the sun off.

Peter