Do you need a gas shut off valve when using gas canisters?

[leideang]

We are taking over the running of a small cafe that has a commercial gas cooker and is supplied by gas canisters that automatically change from one bottle to the other.

We've just been told by a family friend that we need a gas shut off valve fitted near the cooker. Is this correct? It isn't connected to the mains

 

[ShaunCorbs]

Where are the bottles located ?

 

[leideang]

Where are the bottles located ?

Hi, they're outside

 

[ShaunCorbs]

When was the last time it was inspected by a com cat engineer?