Always off when on the move and on when on site.
IF you decide to leave the gas on when travelling as someone has mentioned, and you need to stop for fuel, extinguish any naked flames BEFORE pulling in to a petrol station. Could be a tad exciting otherwise!
------------- Work is the curse of the camping classes!
Thanks for all the replies guys,bit of a mixed bag eh,if it wasnt for the wife nagging i`d leave it on all night but being one for a quiet life i`ll turn it off....thanks Dave
Off for travelling, on when sited. My fridge is only gas/12v, so it has to be left on overnight.
I don't think you should ever drive with the gas on. I'm not sure if there's a law against it or owt, but it seems like common sense to me to have it switched off when in transit.
Turned off at the bottle in transit is good practice as if you have an accident and one of the pipes get split in the van you would have gas pooring out if the bottle is turned on.