With reference to the letter from Rev John Collins on August 23, titled Are 20mph limits really better for us?, I would like to challenge his conclusions.
The statistics recently published by the DfT need to be taken in context.
Firstly, they quote the absolute number of people killed, seriously injured or receiving minor injuries in each speed limit bracket without indicating how many miles of road are covered by such limits.
In the case of 20mph limits, the roads covered are increasing significantly year on year. However, it would seem even the DfT does not know how many route miles are included in such schemes.
A 17 per cent increase in fatalities in 20mph areas may seem alarming – if it were not for the that we are talking about ONE individual (seven in 2011 compared to six the year before).
On such a small sample, statisticians would argue this is not significant.
Since the rest of Rev John’s letter is based on the premise that a reduction in deaths would see a major increase in long-term injuries, I would like to suggest this is now null and void since it is based on such a small number of fatalities nationally.
It is, of course, true that travelling at 20mph will reduce (or indeed avoid) impact of casualties, as both the force of the impact will be less and/or the road user (whether this is car driver, pedestrian, cyclist, motorcyclist etc) has more time to respond to the immediate circumstances to avoid an accident happening at all.
Finally – on the point about reducing speed limits below 20mph – the only authorised speed limits mandated by the DfT are 20, 30, 40, 50, 60 and 70mph. You will see lower speed limits only on private estates (such as Graylingwell Park).
Whyke Lane, Chichester