Even a small amount of airplane noise can have a major impact on sleep: study

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Anyone who has been on a long flight can confirm airplanes don’t make it easy to get some shut-eye — but according to a new study, you don’t have to be on a plane for them to be the cause of a poor night’s sleep.

The study published last month in the peer-reviewed journal Environmental Health Perspectives found women who were exposed to even quiet airplane noises were more likely to get less than seven hours of sleep a night.

Researchers say it sheds more light on how this ambient noise level affects those who live near airports or in places where airplanes are frequently passing by.

“This study helps us understand the potential health pathways by which aircraft noise may act, such as through disrupted sleep,” Junenette Peters, associate professor of environmental health at Boston University School of Public Health and study senior author, said in a press release.

According to researchers, this is the first large-scale investigation into airplane noise and its health impacts.

The study looked at the self-reported sleep levels of more than 35,000 people living near 90 major U.S. airports.

To get a broad base of data, they drew from an ongoing study of U.S. nurses called the Nurses’ Health Study, which has been tracking various aspects of its cohorts’ health through questionnaires since 1976. The cohort only includes female nurses.

Researchers created a picture of increasing aircraft noise levels by looking at the reported levels every five years from 1995 to 2015, including both estimates of nighttime noise levels and daytime noise levels to create an average.

They added a 10dB (decibels) adjustment to the level of nighttime aircraft noises to account for the fact that all other competing noises are so much quieter at night.

The day-night estimate of aircraft noise levels (DNL) is what agencies such as the U.S. Federal Aviation Administration (FAA) use to set limits for aircraft noise levels in order to mitigate negative effects on humans living in the area.

The threshold for significant noise impacts, as defined by the FAA is above DNL 65 dB.

According to the U.S. Centers for Disease Control and Prevention, a whisper is around 30 dB, while normal conversation is around 50 - 60 dB. Prolonged exposure to noises over 70 dB may begin to damage your hearing.

In this study, researchers found that being exposed to airplane noise at average levels as low as 45 dB resulted in those participants being more likely to sleep less than seven hours a night.

“We found surprisingly strong relationships for particular subgroups that we are still trying to understand,” Matthew Bozigar, assistant professor of epidemiology at Oregon State University and study lead author, said in the release.

“For instance, there was a relatively strong signal between aircraft noise and both dimensions of disrupted sleep, short sleep duration and poor sleep quality, near major cargo airports. There is likely more going on to this story, as cargo operations tend to use larger, older, heavily laden, and therefore noisier aircraft that often fly through the nighttime hours. And the quantity of cargo shipped by air has been steadily increasing over the last couple of decades, possibly linked to more e-commerce. If the trends continue, it could mean more aircraft noise impacts to more groups of people.”

The odds of sleeping less than seven hours a night increased as the noise level did, according to researchers, even after controlling for demographics, comorbidities and other environmental factors such as the nightly light level.

However, there was no consistent connection across the board between the reported quality of sleep and the level of airplane noise, despite the connection between length of sleep and airplane noise.

Researchers noted that the study is limited by its scope, as they only utilized a cohort of female nurses, meaning more demographics need to be studied.

“Though we cannot recommend policy changes from the results from a single study, our study of around 90 U.S. airports did reveal a connection between aircraft noise and getting less than the recommended amount of sleep,” Bozigar said in the release.

“Current gaps in knowledge could be filled in the future by including additional demographic groups—such as children, men, minority groups—and more detailed metrics of aircraft noise rather than a nightly or 24-hour average in studies.”

Bozigar added future studies should look into the health impacts of noise from other types of transportation as well, such as cars and trains.