Though sound has largely been ignored in the healthcare industry, several studies have highlighted just how widespread and chronic the issue is. One report by the American Association of Critical-Care Nurses found that from 72% to 99% of all hospital alarms were false. At just one hospital – Johns Hopkins Hospital in Baltimore, Maryland – there is an average of 350 alarms per patient per day.

A global study by the Mayo Clinic found that hospitals had grown increasingly noisy over the past 50 years, with daytime noise levels rising from 57 decibels to 72 and night-time levels from 42 to 60. According to the World Health Organization, night-time noise levels shouldn’t exceed 30 decibels, and exceeding 55 can disturb sleep and increase the risk of heart disease. Another study specifically looked at alarms that signalled arrhythmia (an irregular heartbeat) and found that nearly 90% were false.

“Imagine a neighbour who has a hair trigger car alarm that goes off all the time,” the report reads. “If someone actually breaks into this car, setting off yet another alarm, would anyone be likely to call the police?”

Probably not. Between 2005 and 2010, at least 216 deaths across the US were linked to unheard or otherwise dysfunctional alarms. If anything, this number could be low – alarm-related deaths often go unreported. And while the responsibility for these deaths officially lies with the hospital staff, the root of the issue is largely out of their hands.

“Nurses just start to assimilate that noise. It just becomes ‘beep beep, beep beep’,” says Michele Pelter, assistant professor at UCSF’s School of Nursing and co-author of the study on alarms and arrhythmia. “We also know that nurses are turning the volume down for their own sanity and for their patients and their families.

“In extreme cases, nurses have even totally turned off the alarm.”

This isn’t without reason. Though the auditory neurons in our brains stop firing when a sound or sound pattern is repeated – creating a phenomenon known as auditory selective attention – that doesn’t mean the damage of noise pollution isn’t filtering in anyway, according to a study published in the European Journal of Neuroscience. Exposure to high- and low-level sustained sounds has been shown to cause problems as wide-ranging as loss of sleep and trouble concentrating to more serious issues such as diabetes, depression, and birth complications, according to Science X.

To find solutions, Sen worked with academic researchers in psychoacoustics and critical alarm design to craft sounds that are more harmonious – without diminishing the sense of urgency current alarms create. The result is a set of sounds she helped device company Medtronic to design and which will soon be released to market.