Don’t be alarmed.

Some New Yorkers have been noticing that ambulance sirens are changing their tune from the traditional American wail to the two-toned call heard on emergency response vehicles in European cities like London and Paris.

We’ve imported our new ambulances. #ambulance #europe #siren #nyc

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Mystery solved: Bob Levy, the EMS Supervisor of the Mount Sinai Health System in New York City, told Moneyish that the hospitals are testing more ambient alarms on the fleet of ambulances servicing its seven hospitals to be easier on the ears.

Noise is the number one complaint in the city that never sleeps, and the noise pollution from ambulance sirens is also the most common complaint that Mount Sinai gets.

“We respond to 65,000 calls a year, and then 40,000 of those calls involve patients that need to be transported back to the hospital, so we’re roughly running the siren on 100,000 trips a year. We’re bound to upset somebody,” Levy said.

“But the sirens are important because they alert people that an ambulance is coming,” he continued. “We have to get there, we have to get there safely, treat the patient, and possibly bring the patient back to the hospital safety.”

Noise pollution also takes an economic toll on cities. One report found that residential properties exposed to 65 decibels or louder of railroad noise saw a 14% to 18% drop in property values. Most ambulances run at 120 decibels. Others have found an 8% to 10% drop in property value for places near high-traffic roads and highways. And noise-related loss of sleep, hearing problems and stress can drive up medical costs. England puts its annual social cost of urban road noise at $9 billion to $13 billion. The CDC reports that 10 million Americans have noise-related hearing loss, with 22 million workers in particular exposed to potentially damaging noise on the job each year.

So the 14 emergency units at Mount Sinai’s locations have been quietly testing different siren sounds on each of its $160,000 rigs. And fortunately, a mechanic has been able to change the settings on the existing sirens, instead of the hospital having to order new sirens at $1,000 apiece.

While the wailing sirens and the two-tone sirens are equally as loud, Levy said the two-tone siren they’re experimenting with is less shrill and invasive.

“The traditional siren that you hear [in the U.S.] is called the wail, where it goes up and down, almost like an ocean wave. It’s very piercing, which is why it is the default on most sirens,” Levy explained. “The European alternating high-low tone seems to be more melodic to the ear, and it’s gotten a lot of positive response. And it’s also getting people’s attention better because it sounds so unique.”

Emergency responders have been agonizing over these siren songs for years, Levy noted. Research suggests that ambulance workers suffer hearing loss from long-term exposure to the ear-splitting alarms. And there’s also research to suggest that ambulances running with red lights and sirens on are more likely to get into accidents, particularly at intersections, which has some members of the emergency medical services community calling to use ambulance lights and sirens in less than 50% of responses.

Problem is, the ambulances still need to get the attention of drivers and pedestrians, as well as to assure those in trouble that help is on the way. And as cars have become more soundproof, and people are more distracted by their phones, emergency rigs need to blast a sound that can pierce through the background noise to get the public’s attention.

“To be perfectly blunt, there’s fear on the part of a lot of people in this field that if they change the siren, it will be a liability,” Levy said. “I think we’ve taken the lead on this … and we need a few more months of running through this to prove it works. But I think it’s gonna force others to change, too.”

He added, “We’re trying to find a happy medium where we can assure the safety of the patients we transfer, and our staff, without driving everybody crazy.”