Gas supply shut-off

I’ve seen yellow PEX pipe coming through an external wall from the meter box outside and then transitions to metallic pipe, then to an automatic shut-off valve (connected to fire alarm panel). Next is the manual shut-off valve.

I have been assured that the installation is compliant with relevant standards.

It bothers me that in the event of a fire alarm in the building, the automatic shut-off will activate downstream of the PEX pipe. It will burn away and gas will continue flowing into the firecell.


  1. How does this prevent gas fuelling the fire?
  2. Is there another shut-off valve in the meter box, and if so, why is there another one inside the building?
  3. As the fire engineer, are we overstepping our responsibility?

For my own peace of mind, could someone provide a schematic showing where the safety devices are and how they operate?