"Do the emergency services in Brattleboro use unique sirens? Can I
tell whether a siren is for an ambulance, police car, sheriff, or fire
truck just by listening? If so, how do I tell them apart?"
...
The sirens that BPD purchases are capable of making a variety of sounds. When we purchase sirens we look for the lowest cost (we're always trying to use tax dollars efficiently) while still insuring a quality piece of equipment.
The sirens that are currently in our inventory make three distinct sounds: a longer up-down type siren known as a wail, a shorter frequency siren often called a yelp or hyper-yelp, and the traditional (and somewhat corny in my opinion) European siren that goes "nee-nerr-nee-nerr."
I can only assume that fire and rescue purchase sirens with similar criteria. As long as it is loud enough to alert traffic and is a durable product, it is considered for purchase.
I asked several people in all three agencies and there is no standard siren for each type of emergency responder. As a result, it is probably not possible to determine exactly what vehicle is coming just based on the sound. However, Vermont law requires the same action of drivers regardless of whether the approaching vehicle is a police car, ambulance, or fire truck. That is "all other vehicles shall pull to the right of the lane of traffic and come to a complete stop..." (23 VSA 1050a).
This is a little off topic but I can tell you that police officers are trained to use two different siren settings when traveling to an emergency in multiple vehicles. The reason for this is that upon hearing two different sirens a motorist is more likely to expect two vehicles rather than just one. A motorist pulling out in front of a second emergency vehicle after the first one has passed is a frequent cause of collisions between citizens and emergency vehicles.
If you have a question for the Brattleboro Police Ask-a-Cop please send it to info@ibrattleboro.com and put "Ask-a-Cop" in the subject line.