City Sound Blocks: A Soundscape of Ambulance Sirens

Emergency vehicle sirens are a necessary evil in the urban environment. The combination of lights and sirens are a warning to the surrounding traffic. However, the tonal sounds produced are not always directional, so it can be difficult to tell where the emergency vehicle is coming from. This chaotic reaction includes those in vehicles, pedestrians, and those inside their homes. In my apartment, the walls are paper thin and chances are good that the windows are open.

Within a neighborhood that is neither a rural or densely urban soundscape, the ambulance's piercing sirens can be all the more disturbing. The sirens are both expected and not expected. The sounds are expected because the presence of two hospitals in the neighborhood forms a soundscape of occasional high trafficked sound. Ambulance sirens, helicopters, and car traffic are characteristic sounds of this residential/urban neighborhood.

Yet, the ambulances are unexpected because they cannot be tracked exactly everyday. Accidents happen and as they occur, ambulances respond at any time of the day. The time of day and amount of traffic effect what kind of siren the ambulance will make. Small warning sirens occur when there is less traffic and contains unexpected rhythms and variations of sounds, while a full volume customary siren usually occurs when there is more traffic.

At any rate, the sirens are loud and unpredictable. Although ambulance operators mostly abide by the aforementioned less traffic, more traffic rules, unexpected loudness within a moderately quiet soundscape can be frustrating and daunting. Sometimes in the wee hours of the morning sirens will be wailing enough to wake up everyone in the neighborhood. Is this action too excessive? Many articles describe this exact problem. Are emergency vehicle drivers abusing their power? And are there ways to change the current siren norms?

Both Noise Abatement Society and Rodney C. Lawley's article Emergency Fire and Police Sirens; The Loud Noise Bully of the Twenty-First Century, address issues of emergency vehicle technology and excessive noise or noise pollution.

Noise Abatement Society is a UK based group that raises awareness of noise pollution. They have many campaigns that they lobby for, one topic being emergency vehicle sirens. To end the confusion and non-directional siren technology that currently exists, they are advocating for "a broadband sound siren [that] matches current needs, but [has] greater directivity and less adverse impact on the health and safety of staff, patients, the public, especially at night, and other road users (pedestrians, cyclists and motor vehicle drivers) and the environment (noise nuisance)" (NAS). Broadband sound technology is directional and uses multiple frequencies of sound. However, it is unclear whether this type of technology would be able to cut through loud car stereo systems and general urban noise. There is no agreement as to whether this type of technology would be quieter than conventional sirens.

Lawley discusses emergency vehicle sirens in general (police, fire department, ambulance), but his concerns are also borne out of frustration and distrust in the operators of those vehicles. Also, to combat the "current onslaught of noise" new technology (the Howler) is becoming the standard piece of equipment in emergency vehicles throughout the U.S. The Howler uses a low frequency bass tone to penetrate vehicles two-hundred feet away. Essentially, people would literally feel the siren before they could hear the higher siren frequencies or see the vehicle. The siren would in theory also be able to penetrate homes and residences as it passed by as well. I have not experienced this type of technology yet, however how emergency vehicles are negotiating between noisy urban soundscapes and the need to warn those on the road is disturbing. The stress and physical harm that these sirens are causing is still uncertain.

After a month I was able to finally record the perfect ambulance example. At other times I was not near my recorder nor was not home to witness the sound. However, I hear this type of siren a few times a week. The ambulance nears the intersection by the apartment at full siren volume and then speeds away, while the dogs in the background are howling.