How to Measure Decibels

Question:

How do I measure decibel levels on a sleep phone to ensure it remains below 85 decibels?

Answer:

Many adults may already have some hearing loss in some frequencies. 1 in 3 adults over age 65 have hearing loss. Many things can cause hearing loss, including illness and certain medications. But to prevent noises from causing hearing damage, it's important to control your environment. We recommend keeping all music that you listen to under 85dB to prevent hearing damage. Chuck asked how to measure that, which is a great question. Here are a few ways to measure decibels.

1. A Decibel Meter

   There are entry level to pretty good decibel meters that range from $19 to $60. These may not pass OSHA standards, but they are good enough for most purposes. The professional ones that would pass OSHA standards are about $150 and above. These would be the most accurate ways to measure decibels. Follow the instructions on the meters for the most accurate measurement. Remember that distance from the sound is extremely important.

2. A Smart Phone App

   According to this study by the CDC (http://blogs.cdc.gov/niosh-science-blog/2014/04/09/sound-apps/), the iPhone apps are more reliable than Android apps. 3 apps in particular are quite reliable, missing the mark by only a few decibels, which is comparable to the decibel meters.

   Looking at the chart, the better iPhone apps are:

   • Advanced Decibel Meter ($0.99)
   • NoiSee ($0.99)
   • SPLnFFT ($3.99)
   • SPL Pro ($7.99)
   • SoundMeter ($19.99)

   We do not formally endorse any of them, but they seem like a pretty good solution!

3. Guessing based on comparing with other sounds

   Here is a chart from OSHA:

   

   Here is a link to some other comparisons: http://www.chem.purdue.edu/chemsafety/Training/PPETrain/dblevels.htm

   Vacuum cleaners are about 70dB. Food blenders and hair dryers are about 80-90dB.

   To me, vacuum cleaners are already pretty annoying and loud, and the blender is really loud (enough to make me want to cover my ears). So I would just make sure that anything I listen to is less than that.

Summary

The cheapest and fastest way to keep sounds less than 85dB is to think about how loud a food blender or hair dryer are, and make sure that you keep the music that you listen to less than that. But to be a bit more scientific, for $0.99, you can get a pretty accurate measurement with an iPhone.

Disclaimer: Written by Wei-Shin Lai, MD. This should not substitute for medical advice from your doctor. Please call your doctor if you have questions about hearing loss.