If You Hear a from “Fire Truck Siren”

By: DavidPage

Remember to help paramedics and firefighters get to an emergency faster by hearing a Fire Truck Siren.

  • When planning your next move, make sure to look in all directions for emergency vehicles. You should be aware that there could be multiple responding crews.
  • When you see a green light, stop and look for emergency vehicles.
  • Never stop at an intersection. Continue on through the intersection, and then turn right as soon as you can.
  • Do not slam on the brakes.
  • Do not pull over abruptly.
  • Show emergency personnel the direction you are going by using your blinker
  • Move carefully on the freeway out of the lane for emergency crews. Once again, use your blinker.
  • Do not try to outrun an emergency vehicle.
  • It is against the law to stay within 300 feet of an emergency vehicle responding to an emergency call.
  • Do not stop where an emergency vehicle cannot reach you.

San Diego’s emergency personnel are increasingly seeing motorists who refuse to yield to the sirens and lights of ambulances and fire engines. You could also be causing delays in life-saving medical care by obstructing emergency vehicles’ response.

Sirens. Sirens are loved by firefighters, but they also make people nauseous. Lawyers have become increasingly fond of sirens for generating new revenue streams.

Air conditioning is now a standard feature in modern automobiles. It does a fantastic job keeping unwanted noises out and allowing for desired sounds, such as those from modern entertainment systems, into the vehicle. It can also shield the driver from approaching emergency vehicles sounding their Fire Truck Sirens.

The U.S. Department of Transportation analyzed a siren’s frequency range effective for signal attenuation. This is the amount of signal intensity that loses as it travels through a medium. The medium in this case was an automobile 1952 Chevy Truck with a closed window and typical masking noise.

The test results revealed that the siren sound did not penetrate the vehicle at an urban intersection until the Fire Truck Siren was within 26- to 40 feet.

Sirens for Electro-Mechanical Fire Trucks

The sirens are electro-mechanical and compress air to accelerate it up to 130,000 feet per minute (or 124 miles per hour). The compressed and accelerated air is then passed through a rotating rotor that pulses it to formĀ  a square wave.

As the siren’s guiding throat is 2 3/4 inches in diameter, the resulting column expands and spirals at 9,000 revolutions per hour. The siren’s sound is like an ocean’s waves curling from a short guide throat. On off and on, the variable sound is produced. A foot switch allows the operator to adjust the volume and pattern.