Door Zone

The 'door zone' is an area next to parked vehicles where a door can suddenly open into the path of an unwitting bike user. Not only can this injure people through the initial impact with the vehicle door, a 'dooring' like this can also push people into the road, into the path of oncoming traffic. (A similar result can occur if someone is swerving to avoid a door that has suddenly opened).

Unfortunately many cycle lanes in the UK are painted in the door zone. 

On main roads, cycling infrastructure should run between the footway and parking, not between parking bays and the road. This reduces the risks of dooring, for several reasons;

• people naturally cycle to the left. On the road, this will place them close to parked vehicles; on a cycleway next to the footway, they will be cycling further away from those parked vehicles;
• the vehicle doors adjacent to where people are cycling will be the (lesser used) passenger doors, rather than the driver-side doors, reducing the chances of 'dooring' occurring;
• if a car door does open, people cycling will swerve onto the footway, rather than into the road.

There should also be a sufficiently-wide buffer strip between any cycleway and parked vehicles.