HOW they work in UK ..Variable speed cameras appear and are used on many motorways in the UK, including the M1, M25 and M62. Unlike other fixed cameras and average speed cameras, variable speed cameras don't tend to enforce the road speed limit 24/7, but are used when the motorway's national speed limit, normally 70mph, is temporarily lowered e.g. 60mph or 50mph. These temporary speed limits are set and changed automatically at the press of a button by operators at a control room.
Speed cameras are sited on overhead gantries above each lane of moving traffic, meaning gantries can have up to four or five individual speed cameras targeting each lane of the motorway.
Cameras used at these locations are often the popular Gatso ones, when a vehicle travels in excess of the posted 'variable' or 'temporarily' speed limit the camera is triggered and photographic evidence of the speeding offence is recorded.
IN Ireland they WILL be used as ordinary speed cameras as the legislation allows for it .
