"Why have speed camera warnings?"

I was asked a good question on the NavMii forums this morning, that warrants repeating here...

"in fact if you are sticking to the speed limits anyway why do you need a camera warning at all..."

It's actually a blindingly good question, but not for the reasons you might think of immediately...

OK, think about what happens when drivers see "Safety Camera". Most will glance down at their speedo to check their speed, thus taking their eyes off the road. The two or three seconds involved, bearing in mind that stopping time has direct relationships with reaction time, distance, and speed (see the chart to the left, pinched off the Highway Code website), is crucial for two reasons:

1. It puts you in advance of the mass "look down, smack down" effect, thus giving you a fighting chance to avoid ploughing into the muppit in front who's likely to be standing on his anchors having realised that he's going a bit over the odds, and
2. Having already (if neccessary) slowed down, saves you the indignity of being whumped up the rump by your following vehicle, who also may be in the process of executing a "look down, smack down" manouevre.

Thus by having a warning at an earlier stage in the journey, you are helping yourself avoid the potential for the results of the rippling "look down, smack down" effect.

So, there you have it.

SatNavs with Safety Camera warnings could prevent collisions!