Make sure you do your research and if in any doubt ask a professional. Gas will be outside the range of many basic DIY enthusiasts and it can KILL - Be Safe and follow advice.
In the UK the main LEGAL requirement is that you must conform to is:
The Road Vehicles (Construction and Use) Regulations 1986 with amendments every year. The section that relates to LPG on vehicles is Section 40. This covers requirements and materials for LPG container, joints, valves and pipework. It has a lot of detail on positioning and installation. This is freely available from the UK GOV site. This doesn't cover the same amount of detail as the EN 1949 standard.
The main standards (still aligned between BS & EN at this moment after Brexit)
BS EN 1646:2018 - Leisure accommodation vehicles. Motor caravans. Habitation requirements relating to health and safety.
BS EN 1949:2011+A1:2013 - Specification for the installation of LPG systems for habitation purposes in leisure accommodation vehicles and accommodation purposes in other vehicles
These standards are mainly aimed at businesses manufacturing motor homes and caravans to provide industry best practise, so technically as a self builder you don't need to follow them. However, there has been a lot of thought and experience gone into generating these standards by people with a lot more knowledgeable than you or I so, it makes sense to follow them. If you intend to rent your camper out at some point in the future then I would advise that you follow as many standards as you can. You will need to get the camper certified and doing it right first time is always the cheapest way.
Greg Virgoe has produced a fantastic video as part of his brilliant camper van series that covers EN 1949 so it is well worth a watch as currently it would cost you £218! So, buy a bit off Greg's site as he has just saved you over £200.
Personal safety seems obvious but I’ve seen enough in my working life and on YouTube to realise many people either don’t understand or choose to ignore basic safety.
