Speed limits, schmeed limits

Speed Kills? It's not quite that simple.

The government is trying to get us to slow down. Why? We've already got some of the safest roads in the world, and they had been getting steadily safer until speed cameras started proliferating at a stupid rate. For me, cameras are having the opposite effect to that desired by our leaders.

Whilst I've always driven enthusiastically in national speed limits, I also used to obey slower limits religiously, on the basis that they were there for a good reason. Now, that's not true. I know of many local roads which, over the past few years, have had inappropriately low limits applied, frequently going from a national (60 mph) limit down to 40 mph or even 30 mph. It's too widespread to be simply a "mistake". Of course, the cynic in me steps forward to offer the explanation that the lower the limit, the more motorists they can catch breaking it.

The method that is supposed to be used to set a speed limit is to measure the speeds of traffic along a road over a period of time, and then base the limit on the 85th percentile. There is sound evidence, from many countries, for choosing this speed as the limit. Unfortunately, many local authorities are ignoring the government recommendations, and are setting the limits unreasonably low. Also, it doesn't help that the survey equipment looks suspiciously like a speed trap, so many drivers will artificially slow for it, so reducing the 85th percentile speed.

Now that I have little confidence in the posted speed limits, I find that I make my own judgement about the safe limit for a particular road. Of course, I've always done this, but before if my estimate was higher than the posted one then I'd have held back. Now I am more inclined to go for it. If it's a 40 limit, but the weather and traffic conditions are good, and I can see that there are no hazards around, then I will drive at an appropriate speed. It also works the other way. I often find that in poor conditions (heavy traffic, poor visibility, low grip) I drive more slowly than the majority of the rest of the traffic.

Rather than just spouting "Speed Kills", wouldn't it be better for the government to figure out how to better educate drivers? Then set fair limits, and rely on drivers to have some intelligence in interpreting them? They should use the existing laws of careless and dangerous driving to prosecute people for driving too quickly for the conditions, tailgating, distracting themselves whilst driving (by smoking, using the phone, shaving, reading a book - I've seen all of those). By all means use speed cameras in sensible places and with sensible limits, like outside schools, and near pedestrianised shopping and residential areas. And leave the people who are safely doing 90 mph alone.

See also:
SafeSpeed: a sensible "S.P.E.E.D. kills" campaign.
Association of British Drivers: increasing US speed limits reduced fatalities.
Peppipoo. Lots of good info for fighting a speeding ticket.



This page is http://www.strangely.org/diary/200510/speed.html. It was first published on Monday 24 October, 2005 and last updated on Monday 24 October, 2005.