Where the guidelines apply
The PNGRB guidelines for gas supplies to multi-occupancy residential buildings (2020) cover buildings where natural ventilation is not available. In such buildings, the gas installation needs extra safeguards, because gas that escapes has nowhere to go.
Detectors and automatic shut-off
The guidelines ask for gas detectors that meet BS EN 60079-29-1 and -2 or an equivalent, with at least two installed. They are interlocked with the shut-off valve, so a leak closes the gas supply, and they are backed by hooters that warn the people nearby. The gas solenoid valves must not be bypassed.
Monitoring 24 hours a day
A centralised building management system should monitor the gas safety systems all day and every day. Its working must be demonstrated at intervals of no more than six months, so that a fault is found before it matters.
Emergency access
A fire-rated door is required at each level, so that the shaft can be reached in an emergency and a fire does not spread through it.
Ventilation and risk assessment
Adequate ventilation comes first. Where natural ventilation cannot be provided, a risk assessment following IGEM/G/5 is needed. The guidelines also require a recorded risk assessment of the whole building, covering the hazards, the people who could be affected and the controls in place.
What to check at handover
Check that the detectors are in the specified places, that they trip the shut-off valve when tested, that the hooters sound, that the monitoring system shows the right signals, and that the records are kept for the building operator.
If you are planning the gas safety systems for a tower, send us the building details and we will outline what the design should include. See our PNG riser stress analysis service.