Even my 3 year old daughter knows what red, amber and green mean. No wonder that countless information systems exploit this colour system as a visual aid, usually to great effect.
Southeastern Railway – operators of the Metro, Mainline and Highspeed rail networks – have chosen to blaze their own trail:
The photo above is the Big Info Board at Charing Cross train station, which you usually first glance from 100 feet away – so the low-key second column (Good Service) is hardly visible. Southeastern would have done well to consider this context when planning their colour system.
The separation of trains into the three networks provides little benefit to the end-user, who is seeking for info on their train only, usually in a hurry. The Big Board table could be improved by adding sub-group headers (Metro, Mainline. Highspeed), but better to scrap the network colour system altogether, and use a traffic light system for the Status column to the right.