Road safety policy for fifty years addressed the behaviour of the road user.
Campaigns, licences and all assume that the is a failure of a person.
The alternative approach begins from the observation that people will always make mistakes.
A system that turns an ordinary mistake into a death is a badly designed system.
The human body fails at known speeds, and those numbers are the design input.
A struck at thirty kilometres an hour usually survives; at fifty, usually does not.
Streets where the two mix are therefore designed so that fifty is difficult to reach.
Narrow lanes, raised and tight corners achieve this without a single sign.
is then needed only for the minority who defeat the design.
Separating users by speed is the other half of the method.
Where separation is impossible, speed must fall to the level of the weakest user.
Countries that adopted this framework reduced deaths while traffic rose.
The obstacle is that the results appear slowly and the inconvenience appears immediately.
A resident notices a longer journey this week and cannot notice the that did not happen.
Publishing the figures by street is the only way found so far to make the second visible.