HIS re-examination complete, rail expert Nick Gallup is explaining the complexities of rail gauges to inspector Andy Mead.
The system, designed to ensure rail trucks do not hit or clip bridges, tunnels or station platforms , gives a classification to every piece of track.
Mr Gallup has explained that different gauges are needed depending on the type of containers and rail wagons used, taking into account the possibility of fitting a short and wide load into a tall and thin gauge.
Rail lines serving coal mines or heavy industrial plants, he explained, need different gauges from those linked to distribution depots, ports and the Channel Tunnel.
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