LPG is not high pressure.

CNG is high pressure.

LPG is 8 bar in a cartank, filled 80%....now put that tank in the sun and see the pressure go up...untilllllll

It doesn't matter how high the pressure is (CNG has 200 bar) it's what the tank is designed for.....and if the tank has a pressure release valve for emergency or it will say BOOM.

In my homecountry it's very illegal to fill bottles at the lpg-pump but some folks weld the right connector on their bottle and still do it.

You're right of course.

You know, if Thailand jury/government system had any competency at all, they wouldn't have all this scam crap going on. But then, what am I talking about? Going beyond competency, you have to get past ethics, as well. There is no hope for Thailand...