What is diamond sign that now appears on major road near my French home?

Reader question: A major ring road near my house has a diamond sign on the road, that I have never seen before? What does it signify? 

The diamond or ‘lozenge’ system is becoming increasingly common across France, and is the basis of an extended trial. 

Since 2023, the trial has been using the symbol – a white diamond on a blue background – to inform users that a lane on the road is limited to certain vehicle types. 

Found most commonly on dual carriageways and city ring roads, it indicates that a lane – usually the left-most – is off-limits to vehicles without any passengers. 

The lanes will be restricted to: 

• Vehicles with multiple occupants, either in the front seat or back seat (including motorbikes with two people on them)

• Vehicles that are 100% electric, 100% hydrogen, and have a Crit’Air sticker. In this case, there does not need to be multiple people in the vehicle, but hybrid vehicles are not included

• Official taxis, even with no passengers (ride-share drivers can usually only use the lanes if they have a passenger inside)

In short, it denotes a lane is a car-sharing one, with certain other vehicles also allowed.

Roads where the rules are in place use high-tech cameras that can assess whether a vehicle has a suitable Crit’Air sticker or multiple passengers (including children and people sitting in the back seat).

In some cases, whether rules apply depends on the time of day – usually implemented in rush hour - with electronic signage indicating whether the rules are in force. 

If you drive in the lane without authorisation, you face a fine of €135.