Bristol is about to go into a review of its 20mph speed limits.
The arguments around removing 20mph speed limits always focus on how they do not work and people *still* speed through areas. Even the DfT admitted 80% of drivers broke the 20mph speed limit. Yet you will find that the average speed on a 20mph road is around 23-24mph.
What people fail to recognise though is that the impact kill curve is not linear. Hitting somebody at 23mph is of an order of a magnitude less deadly than hitting somebody at 27mph.
When seatbelts became mandatory, pedestrian deaths went up as people felt safer in their cars and drove faster. 20mph speed limits and zones (where the road is designed to make it hard to go faster than 20mph), are key to redressing this balance and preventing the continued whole sale slaughter of pedestrians, the biggest group of victims of road violence.
Let’s not forget that we should also be implementing cheap Low Traffic Neighbourhood Cells within our cities to reduce road deaths, air pollution, and get more people walking and cycling. 20mph speed limits and particularly 20mph zones are key to making these successful.