Addition to my last post (Patreon)

Guys, thank you so much for your advice. Forgot to mention though that the gas system in the caravan has this thing as well so i can turn gas on and off with these nobs for each item, the onnly one left out of these three is the gas hob.. would that not be sufficient if i just turn the fridge and heater nobs off as they no longer exist only leaving the hob on? Or do i still need to seal the pipes off which connected fridge and heater to the gas supply???