Gas network evidence¶

The gas network leaves a different record from the electricity net, and a thinner one. Real-time telemetry reaches the pressure-reduction stations but rarely the street mains, and the safety that counts most, the mechanical chain that shuts a station on over-pressure, works without a control room and so without a log. What proves the network safe is largely periodic: a cathodic-protection potential, an odorant check, a leak survey, a permit to open a live main. So the gas record leans on measurement, inspection and paperwork, and its signatures are as much about missing or stale records as about anomalous ones.