So we need a sticker on all our vans and cars saying they contain fuel in a tank as when we have a fire for what ever reason and they catch fire and explode and send every shrapnel everywhere. NO, its a safe as you allow it to be and the time you spend checking to see if any leaks are fixing. If you are not sure fit a gas detect alarm or don`t use them if you are a fear driven person.
A few points here -
1-unless its full electric every motor vehicle on the road will have fuel in a tank , a very low percentage will have a gas cylinder in the back.
2-Yes fuel tanks can explode although this is fairly rare and when they do its just a momentary fireball that a firefighters fire kit would withstand .(diesel wont burn until its either heated or under pressure).
3- Car fuel tanks are not pressurised cylinders - gas bottles /tanks are at high pressure and when subjected to the intense heat of a fully alight car/van will explode and the shards of metal from the cylinder can slice you in half , nothing your wearing will protect you from that .
4- You can check for leaks all you like and maintain it all in perfect condition ......that doesn't stop your car/van catching fire for other reasons (usually electrical) , i have been brand new vehicles including a two week old vw transporter that have caught fire due to electrical faults.
So yes it would be a good idea to put the sticker on your van, they cost very little !
I really do wonder about some people !