Do the sirens that ambulances, police cars, fire engines use make different sounds. If so, how can you tell?

Question

Is there a subtle difference? And part of the questions is why would they need to have different sounds, who would this help?

Answer 1

WOW Craig! You got a ton on answers on this one!

If I buy a model XYZ (example model number, not an actual one) Federal Signal Tone Generator and a 200 Watt speaker at attach it to an ambulance will it sound differently if I attach it to a police cruiser and put it on the same setting? I think not!

It's popular and customary to put those older "motor driven" sirens on fire trucks that create that long high pitched whirr, but I suppose if I wanted to put one on an ambulance, there's nothing to stop you. I have seen a few with those attached to them. It's not as easy to put an "air horn" on a vechile that doesn't have air brakes, but it can be done if you really want to. I hooked one up to a CO2 bottle once... worked great! Hell of a lot of fun too to put one on a car... NO ONE EXPECTS IT! Often firetrucks employ multiple warning devices, while a police car usually only has 1 siren. Why? Well, if the siren goes out on a police cruiser, it's easy enough to grab another car for the day. Fire apparatus and squads may not be as handy depending on the size of the department, but I digress...

Bottom line, it's not exclusively about the vehicle, it just about what warning devices have been attached to it. Heck, my local police department doesn't even have the same sirens on each of thier police cars. Doesn't mean anything really, it was just about the model available at the time.

Answer 2

Yes they do. Police cars typically use one siren system, while fire trucks use two or even three. Usually ambulances use 2 or 3. Fire trucks typically use an air horn like an 18 Wheeler, while police cars have an electric air horn. Fire engines also usually have a round stainless steel siren on the front bumper which sounds something similar to a wind up siren. The difference between an fire engine and an ambulance is very subtle and it takes an experienced ear to tell the difference, however the difference between fire and police is distinct. As for why they have different tones I do not know for sure. There are however many different manufactures of siren and light systems and each police or fire vehicle builder probably just likes the performance or has just used the same manufacturer for years. The need for diff tones depends upon the situation. Some tones travel farther while others are very distinct at short distances, such as intersections.

Answer 3

I can't answer for all cities, but I am a firefighter for the city that I live in. Our Fire and most of our police cars have the same siren systems installed in our vehicles. The systems allow for up to 4 different tone variations that can be switched at anytime while driving. Each is very unique and can be distinguished from one another. Sometimes the subtle difference can be caused by different systems. There is no requirement to have matching sirens in each of the fire, police, and ambulance vehicles. One system could cound higher than another, even on the same tone.

On a fire call, we will use a certain tone the entire time until we get to the location. There is no set tone that we have to use, but there is one tone that is the "norm" that we will almost always use. We have a 5th siren on the truck that is used near intersections coupled with the airhorn. Our policy is to always use the airhorn when comeing to an intersection that either has a stop sign or stop light. The 5th siren is optional, but most use it.

The police in our city have their own guidelines for tones. For the most part, they will switch to a more frequent tone when going through controlled intersections. There are times where the fire and police are using the same tones, but nobody really cares. The most important thing is that we are heard and seen so we can get to the emergency in a timely and safe manner.

The different tones have different wave lengths, and will have different distance ranges. Some have longer wave lengths that will project farther out, while others are best used for shorter distances, like coming to an intersection. Its basic Physics. And I thought I would never use that stuff!

Answer 4

There is no standard siren for any branch of emergency services. It all depends on what the department buys. In some areas all three departments will use the same siren, and in other they will all use different ones.

Where I live the police use a standard electric siren. EMS uses an electric double siren. Two sounds are used at the same time. The fire department uses either a standard electric siren or an air powered siren, which is similar to an air raid siren.

The best way to tell is just listen to the siren of each vehicle when it goes by and compare them.

There is no real benifit to having all the same or all different sirens. Regardless of what kind of vehicle is using it you still need to get out of the way..

Answer 5

Yes, the three services do have different sirens. The only way to tell the difference is through experience. However, it's not as simple as it used to be.

In the 'old days' there was a specific sound for each one of the three. A police car would sound like a police car everywhere.

More recently, within the police in particular, there has been experimentation with alternative siren sounds. 'White noise' has been used by a number of forces in an attempt to increase driver awareness etc.

In short, there are still key tones for each of the services, but there is also more variety than before. Don't worry about which one it is ...... just get out of the way!

I'm not an expert, but I hope that helps.

Answer 6

Sirens on emergency vehicles are not particularly different - ie you cannot necessarily TELL whether it is police, fire or ambulance.

However, different areas have different vehicles and consequently have different sounding sirens. Many are beginning to sound much more American now - the big blasting hooter type noise.

Many emergency vehicles now have three different types of siren - warblers, wailers and white noise. Warblers and white noise work better in heavy traffic and built up areas. The white noise is more directional - so it should help other road users identify the direction the vehicle is coming from. The wailers are the longer tones used on clearer roads.

Answer 7

Fire Engine Sounds

Answer 8

Police Siren Soundboard

Answer 9

There is no easy way to answerthis question. I've been a paramedic for 16 years and volunteer as a firefighter in my off time. Generally siren manufacturers build their products to be used by any service that wants to purchace them. As an agency you can chose to use whatever type of siren that you want. EVOC (emergency vehicle operations courses) differ from state to state, but most require that the sound be changed at certian distances from intersections to warn oncoming traffic. Usually the only way to really tell the difference, aside from visually, is knowing the policies of each department. One other concideration is that the standard Q siren is generally used on fire engines due to it's size.

Answer 10

I worked for 7 years at an Acident & Emergency unit and came to recognise the different sirens pretty well and can tell the difference straight away, so yes they are different.

Ambulances would always turn off their sirens on approach to the A&E unit - if they kept them on all the way to the main doors this meant that there was an emergency and that the paramedics required medical assistance on the ambulance. It is therefore important to be able to recognise what type of emergency vehicle is on its way.