As a sound designer for film, part of my job is to record replacement dialogue due to noisy background sound contaminating the original dialogue.

I then have to re-create the backgrounds and make them sound realistic while maintaining intelligible dialogue. Thus, I have become a bit of an Angry Nerd when I watch movie scenes that take place in airplanes with virtually no cabin noise and with actors who deliver lines with zero vocal effort. Suspension of disbelief doesn’t work on me here. Airplanes are loud.

Is Airplane Cabin Noise Dangerous?

The short answer is, yes, it can be. The long answer is, it depends. In the ten years or so I’ve spent measuring sound levels in airplanes, I’ve found that cabin noise can range from the low 70s (dBA) to the low 90s. Yes — the 90s! Egad. Typically, smaller planes are louder, and, fortunately, long haul, international flights tend to be quieter. Also, you’ve probably noticed that the back of the plane tends to be louder (engines are sometimes in the tail), as well as near the wings (engines are usually near the wings). As we know, sound level and duration of exposure determine whether a person is at risk for hearing injury, but if a patient asks for a simple rule to proactively prevent injury, you might advise them to wear hearing protection (earplugs, isolating earphones, noise-canceling headphones, etc.) if the flight is over 2 -3 hours and assuming they are not taking a private jet. Remember that according to NIOSH, exposure to 88 dBA for over 4 hours is potentially hazardous, and at 91 dBA only 2 hours!

How Helpful Are Noise Canceling Headphones, Really?

The short answer is, very. The long answer is, that it depends. Active noise canceling (ANC) head/earphones can be extremely effective in reducing low frequencies (typically 700 Hz and lower). However, not all devices are created equally as we know. Some headphones dramatically reduce noise (like Bose Quiet Comfort and Sony WH-1000XM5). Others reduce the lows but have an audible, internal noise floor (Airpods Pro). Others still reduce the lows only a smidgen and I swear, seem to amplify the cabin noise compared to your naked ears when the ANC circuit is off.

However, if we’re using objective tools like a sound level meter to determine what is safe, then ANC alone might not reduce the sound level by much since NIOSH and OSHA use the dBA-weighted scale. So we also need to pay attention to…

Passive Attenuation

Passive (no electricity) isolation, or the attenuation of sound simply due to the earphone or headphone acting like an earplug or earmuff, will help reduce all frequencies. Like with earplugs and hearing aid earmolds and domes, seal, insertion depth and the material will affect attenuation. So, we want head/earphones with a high-quality ANC circuit as well as good passive attenuation.

Still, even a mediocre ANC circuit is not for naught, as a modest amount will help keep media volumes lower. Two studies* demonstrated that people tend to turn the sound level up 13 dB higher than the surrounding noise. If the cabin noise is 85 dBA, and we use the airline-provided earbuds which seal poorly or not at all, that means we could easily be listening to Ferris Beuller’s Day Off at 95 dBA! Nobody’s ears need that.

Right now, summer of 2022, there is a surge in airplane travel even with notoriously-common canceled flights and sky-high (pun intended) ticket prices. Patients may ask about the best way to reduce noise and listen to their music, podcasts, meditations, or movies without blasting their ears.

*Citations:
Fligor B. Recreational noise. In: Chasin M, ed. Hearing Loss and Noise. Sedona, Ariz: Auricle Ink Publishing; 2010:Chapter 4 citing Airo E, Pekkarinen J, Olkinuora P. Listening to music with headphones: an assessment of noise exposure. Acustica. 1996;82(6):885–894 and Williams W. Noise exposure levels from personal stereo use. Int J Audiol. 2005;44(4): 231–236.

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