Ambulance Sirens

If you’ve ever been driving down the road, heard the whir of an ambulance siren, and caught a glimpse of flashing lights speeding towards you, you’ve probably been grateful for the warning.

Siren, as a word, has its origins in Greek mythology where it was associated with the dangerous songs of mermaids who lead sailors to their watery graves. Today’s ambulance sirens are more often associated with caution, rather than danger.

Ambulance sirens save lives by alerting other motorists to the presence of an emergency vehicle so those motorists can exercise extreme caution while the emergency vehicle travels by them at a high rate of speed to respond to an emergency or deliver a critically ill patient to the hospital.

Ambulance sirens compel such caution, in fact, that there’s a legal penalty for not yielding to the emergency vehicle. In the state of Washington, failure to yield to a police car, ambulance, or any other authorized emergency vehicle using visual and audible signals, i.e. lights and sirens, can result in ticket and a fine of more than $1,000.

To generate all that caution awareness and help people avoid steep fines,  ambulance sirens have to be able to penetrate the seemingly hermetically sealed passenger cabins of today’s highly evolved vehicles.  In the early days of ambulance sirens, emergency vehicles were outfitted with a mechanical bell, mounted to either the front or the top of the vehicle. On today’s ambulances, most sirens are electronic and produce a range of noises with the operator can alternate to achieve maximum traffic dispersion in heavy traffic or crowded intersections.

Most siren manufacturers build sirens that work on a variety of emergency vehicles, but there are some manufacturers, such as Carson, who build sirens specifically for ambulances. The SA-441 Magforce Mechanical Siren combines the traditional mechanical tone and the Carson “stutter” air horn with a powerful, independent, two-channel, 200 watt amplifier to clear the streets quickly and effectively. Because it features a dual tone audio output with siren tones and the mechanical tone, it gives surrounding motorists the impression that there are two emergency vehicles with their sirens on in the area at the same time.

Next time you see an ambulance in your review mirror or hear a siren passing in the night, consider the technology that keeps you safe.