When
out with traffic police, I noted much of their use of lights, siren and their decisions to adhere to speed limits or not – with or without emergency equipment being used.
Lights – a vast selection is available for their use. These comprised:
- 360degree revolving blue lights – on roofbar
- front flashing blue lights – on roof bar
- front flashing blue lights – on grill/front bumpers
- rear flashing red/blue lights – either roofbar or within vehicle rear lamp cluster
- flashing headlamps – daytime use only, per ACPO guidelines
- or all on (a “999” switch) including activation of siren
Siren – 4 types I noted available:
- wail
- yelp
- 2-tone
- Buzz (or something, can’t remember that one exactly)
The sirens (once activated by the master control switch with the light controls) is switched on/off via the horn press on the steering wheel. If the siren is off, a single press will switch it on, and then another press will move on to the next siren type and so on; 2 presses will switch the siren off. This is why you often hear the horn bleep when they switch their sirens on/off.
As for siren use, and lights for that matter – they are only used to alert other road users of their presence. To leave the sirens on all the time defeats the element of surprise (no, really) as the siren coming on is the most important noise it can make; once it’s wailing away it loses effectiveness. What was noted in town driving the sirens were used to alternate types when traversing junctions, going on roundabouts, over pedestrian crossings etc, and then switched off.
At high speed on a fast road, again their use was very marginal as the sheer speeds involved made their noise virtually useless against normal traffic noise.
When approaching a vehicle from behind on a dual-carriageway, the police car would get exceptionally close to the rear bumper, positioned very much in view of the drivers’ door mirror of the vehicle in front – lights are more effective than noise (plus much gesticulation from the police driver
)
As for high speed with no lights/siren, this seemed to be commonplace – very notable when they were responding to an incident where it was not an A-grade (I think other forces use a different grading system, but Cambs have an A-grade has a priority call) but on a so-called “hurry up” where attendance was needed but not critical to get there as soon as they could.
Sorry for long post!
