Having busted through many a traffic light going as quickly as possible on my way to the local donut shoppe… I will have to say that we often just used our fingers, not some study, to determine which siren to use.
The average police car has all of the aforementioned sirens in his catalog of sounds and few that he or she may just not use.
Most often, we will switch between one and another, “our favorites”, and then flick the air horn when approaching an intersection. They are most often arrayed as a bank of toggle switches on a small box amongst the thousand other things that a cop must fiddle with while driving (his computer, his heater, the coffee, the fresh donuts, the radio, the radar gun, your partner). You guys think you have distraction issues!
People don’t hear sirens and they don’t hear the horn. So, I just generally did what any law abiding cop would do: yell from my closed windows “GET OUT OF THE WAY YOU MORON!!!” and merrily went on my way.
One possible addition, which is coming into use, is priority signals. The emergency vehicle sends a signal to the traffic signals ahead, which then cycle to green to clear the way. It won’t supplant sirens. It’s pricey, and unlikely to be installed on all of a city’s signals. And if the system goes out, at either the vehicle or the signal end, you’d want a backup.
My problem isn’t with real sirens, it’s with sirens from the radio. On two different occasions I was listening to a story on NPR and as part of their on-the-spot, you-are-there reporting, the played a @#!$! siren. I immediately slowed down (in traffic) and tried to figure out where the siren was coming from. Another time, NPR decided their story needed to include a cell phone ringing. Considering that the bulk of the NPR audience listens while driving, this seems stupidly dangerous.
As a firefighter for 8 years now my experience has been that it comes down to driver awareness/selfishness, and distractions. Cell phones, radios, air conditioners etc are all part of the problem contributing to lack of driver focus. Those annoying radio sounds, including cell phone rings, sirens, and horns played on the radio to get your attention contribute to desensitizing drivers, but my experience has been that the major issue is driver indifference. I kid you not but on several occasions I have been responding to a call in a structure engine, running code (lights and sirens) and have been passed on 55 mph, two lane roads by private citizens. (Law enforcement gets a plate number over the radio when this happens…)
I say it is selfishness because unfortunately we recently had a civilian run a stop sign and pull in front of a department truck that had right of way, was operating at the speed limit and was running code, resulting in a civilian fatality. Since this happened there has been a noted positive difference in private vehicle behavior in the region that multiple departments have commented on. Nothing else has changed as far as lights, sirens, or response behaviors except that awareness seems to have gone up. People seem to be paying attention and that seems to be making a difference. So I would suggest that driver attitude is the major variable that needs to be tested.
In the UK I rarely see an emergency vehicle running with the siren on while “Hot”. They turn it on for a moment if they need it, such as a bunch of traffic ahead, but if they way looks clear they leave the lights on and turn off the noise. It’s a tool, not a weapon after all.
I’m old enough to remember, and miss, the old mechanical wailer. (I think it had already been replaced in Europe by the time I was a kid.)
I’m also old enough to remember that you could get one that mounted on your bike. (The difference in volume was enough that only a very silly person would confuse one with the real thing.)
I was driving home the other day and heard a siren behind me. I looked in the mirror for the lights, only to have NPR play a clip with a siren in it at the same moment, distracting me from the very real ambulance behind me. For such an intelligent radio station, they do really stupid things.
Huh? That siren, which was electromechanical, rose and fell with the speed of the motor operating it, which was independent of vehicle speed. I think you are thinking of vacuum windshield wipers. Their speed depended on engine vacuum, and changed according to load and how much you needed your windshield wipers–if the car was parked they worked great but if the car was accelerating they would slow or stop.
its been 25 years since i was a medic, but back then, you could get siren tones inbetween the siren settings, sorta combining the 2 its between. you could get a rising ping for example. every new guy had what they believed was the most effective sound for the particular environment. old farts just turned it on and what ever it was on it was on. illegal but polite, in the wee hours of the morning, i’d often just run lights. if you couldn’t see that you were’nt watching anyway. it let people sleep and attracted fewer gawkers. we were always prepared to stop at an intersection and i’m alive because of it. jim
Many US states require non-police emergency vehicles to use the siren continuously in emergency mode. It’s kind of a pain in the ass and people don’t always do it, but is the rules.
Back in the early 70’s I worked at a Seattle FM rock station. One of the nightly features was called the 7 o’clock side, one side of a popular album of the time would be played. Of course, many folks took advantage of this and would record the album off the air. The local FCC decided that the station was violating the rules, the dead space between songs was an attempt to make the music recordable. The station was ordered to fill the dead air gap between songs. The DJ’s had a variety of sound effect tapes available, all one had to do was press a button corresponding to the tape player and the sound effect was broadcast. One particular night Ted Nugent’s first album was the 7 o’clock side. I was at the controls and just as Stranglehold ended, I hit the button for the sound effects and it was a siren. It only played for about 5 seconds then I shut it off as the next song started. About 5 minutes later a call came in, some guy was on the road and just happened to be smoking a number when the siren sound was played. He said it scared the crap out of him. For the next 2 hours, the station got at least 20 calls from folks about the siren including some guy that said he ran off the road. The next night there was a note from the station manager, no sirens over the air. I was a victim of this myself a number of years later, there is a siren at the end of the song Last Child by Aerosmith. It had me looking for flashing lights for a few seconds.