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Crying wolf
Page 64
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My colleague reports that, in foggy conditions at least, police views are often out of touch with patchy fog. On the M6 last week, the illuminated speed limit signs were all in use but frequently bore little relation to actual conditions. Near the Corley service station, for instance, several signs were justifiably set at 20mph. Then one read "40mph" just as the fog got thicker! And within half a mile he came upon a serious accident — one in which a lorry driver was badly injured.
Further north, signs were persistently set at 40 when conditions safely permitted 60 mph driving. All too often, in non-foggy conditions, warning lights are used for accidents or road works that took place some time earlier and the road has subsequently been cleared. This constant crying wolf has the effect of reducing the effect of these signs. And in fastchanging weather conditions the speed signs need to respond quickly if they are not to be ignored.