Done a lot of driving of late (most recently to a wedding at Brocket Hall, as in Lord Brocket, I’m a Celebrity.. and all that), and pre-Ben driving was a social experience with the missus, but these days she’s usually in the back looking after him, so we can’t really talk.

Although it’s sad not to be able to chat, it does leave a lot of time for thinking, mostly about driving, which probably figures. Anyway, latest jaunt along the M1 I was thinking about speeding, and speed limits. Why bother with speed limits at all?

I reached two (related) reasons for having a speed limit – first, and probably most importantly, it reduces the likelihood of accidents, for reasons I’ll elaborate on in a mo. Secondly, if there is an accident, the slower the vehicles involved are travelling, the less harm is likely to be caused to those involved.

So why does a speed limit reduce accidents? Well, the conclusions I reached were:

  1. At higher speeds, things happen more quickly (relatively non-withstanding). During a 2 second glance in the mirror at 70mph, you travel about 60m. At 100mph, it’s about 90m – or something like 15 car lengths further. Similarly for reaction times.
  2. If something does happen, you’ve got more speed to shed.
  3. Cars are generally less stable at higher speeds and heavy braking, raising the likelihood of swerving/skidding/drifting into other cars, barriers, etc.
  4. Speed differentials will be higher. What I mean is a 60mph wanders into the fast lane, a car coming up at 70 is a different proposition from one hareing up at 100. This is true of coming up behind other cars too – I’ve been caught out even at 70 when a Lorry or caravan has been going more slowly that I had thought.
  5. Higher speed impacts will spread debris/cars/other obstructions further afield, raising the likelihood of further accidents.
  6. Slightly more dubiously, driving faster may increase adrenalin, ‘pump you up’, making you more likely to make a silly mistake.

Arguments the other way probably would say things like modern cars are very stable, have lots of driver aids (like ABS), good crash protection anyway…

Dunno – shall post some thoughts on why people speed later this week, I think.