iSAFE, cell phones, and sounds some can't hear

Image from: http://www.flickr.com/photos/bjmcdonald/4494079025/

One of the most enlightening tidbits from the iSAFE session this morning may have been about cell phone ring tones that “adults” cannot hear. Although I had heard of this and seen websites a couple years ago, as a former science teacher, I had to do more investigating regarding the science behind it all and thought I’d share a little...

Notice from the chart below that younger folk (aka – our students, children) can apparently hear tones closer and possibly beyond the 20,000 Hz (hertz) or 20 kHz, as can rats, cats, dolphins, moths, mice, and sea lions. Insert your comments here: _______

From - http://faculty.washington.edu/chudler/facts.html

Hearing Range (young adult human) = 20 to 20,000 Hz
Hearing Range (elderly human) = 50 to 8,000 Hz (Guyton, A.C., Textbook of Medical Physiology, 1986)
Hearing Range (rat) = 1,000 to 50,000 Hz
Hearing Range (cat) = 100 to 60,000 Hz
Hearing Range (dolphin) = 200 to 150,000 Hz
Hearing Range (elephant) = 1 to 20,000 Hz
Hearing Range (goldfish) = 5 to 2,000 Hz
Hearing Range (moth, noctuid) = 1,000 to 240,000 Hz
Hearing Range (mouse) = 1,000 to 100,000 Hz
Hearing Range (sea lion) = 100 to 40,000 Hz
(Hearing range reference: Discover Science Almanac, New York: Hyperion, 2003)
Most sensitive range of human hearing = 1,000-4,000 Hz

And if you’d like to have your children or students tell you when your phone is ringing, here’s a website for you to test your hearing and/or download one of these ring tones — called “Mosquito Ringtones.” Better yet, for those w/ a home phone that never rings for you, maybe this tone can be used for that as well (just kidding).

Note that (for good reason) this site is blocked at school, so try it at home! A variety of tones are listed that you can test and then determine what you can/can’t hear. FYI — 18.8 kHz was my highest threshold! I feel so young!!! With all the loud music via earbuds, I wonder how soon kids’ hearing will no longer be able to hear these high pitch sounds.

http://www.freemosquitoringtone.org/ 

Lastly, here’s a NYTimes story about it... From 2006 (it’s only been 4 years you haven’t noticed kids getting cell calls/texts... Not too bad!)
http://www.nytimes.com/2006/06/12/technology/12ring.html?_r=1