October is National Protect Your Hearing Month, providing a perfect opportunity to remind my readers about the importance of guarding their ears against potentially damaging, high decibel noises. The harmful effect of loud sounds is well documented, as anyone who has served in the military knows all too well. However, a recent news story on “sound cannons” underscores just how crippling sound can be.
A device called a long range acoustic device (LRAD) was used in late September by Pittsburgh police as "sound cannons" to blast the ears of protesters near the Group of 20 meeting of world economic leaders. The police used the device as a means of crowd control that delivers an "unmistakable warning," according to the manufacturer of the instruments. Its shrill warning tones can be heard at least 1,600 feet (500 meters) away and depending on the model of LRAD, it can blast a maximum sound of 145 to 151 decibels — equal to a gunshot — within a 3-foot (one meter) range. That easily approaches the noise generated by a jet engine, which emits a deafening 140 to 180 decibels of sound. Permanent hearing loss can result from sounds at about 110 to 120 decibels in short bursts or even just 75 decibels if exposure lasts for long periods, according to the National Institutes of Health (NIH). You can read the full story here.
A helpful guide for measuring the safety of various sounds can be found on the website of the American Academy of Audiology by clicking here.
Remember, even seemingly harmless devices like MP3 players can cause damage if played loud enough. Protecting your hearing is critical because once it is damaged, it is not reversible.