Wednesday, June 30, 2010


Okay, so I've been procrastinating about writing due to the World Cup. I feel positively European, since I can tell you which 8 games went on this week and who's advancing and when the next games are. One of the big to-dos about the games in South Africa is the use of the Vuvuzela, a traditional horn used there for soccer games.

At one of the U.S. games (I think it was England, if not it was Algeria), I saw two men in the American fan section wearing ear plugs. I was so amused (pleasantly). You could see the little yellow ear plugs, which means they probably weren't inserted exactly the right way. But, given the fact that these traditional horns can produce up to 120 dB(A) at 1 meter @ 1 kHz, I finally agree that any amount of noise reduction is a good thing. What I really want to know is who these two fellows are and why they thought that was a good idea. Do they already have occupational exposure to noise? Are they industrial hygienists or safety professionals or occupational medicine nurses/doctors? Or did they just decide 'hey, this is going to be really really loud, let's bring ear plugs!"

There are countless studies published on noise induced hearing loss (NIHL) and many involving sports-related exposure. Two months ago, immediately prior to the World Cup in South Africa, several articles have been published about the vuvuzula in particular, as well as - of course! - a Wikipedia page on health effects.

So, in summary, they're really really really loud.

original cited research (if the article is on-line, I included a link):

Swanepoel D, Hall JW III, Koekemoer D. Vuvuzela – good for your team, bad for your ears.
S Afr Med J (2010) 100, 4, 99-100.
with a follow up report from the authors explaining their noise measurement method & providing a table of results:  122 dB(A) at 1000 Hz and 2000 Hz at the bell opening.

Swanepoel D, Hall JW III. Football match spectator sound exposure and effect on hearing: A pretest-post-test study.
S Afr Med J (2010) 100, 4, 239-242

Berglund B, Lindvall T, Schwela DH, Goh KT, eds. Guidelines for Community Noise. Technical Report. Geneva: World Health Organization, 1999.

According to South African media Sports24, 1.5 million of these things have been sold in Europe since October.  If they were all being manufactured in South Africa, I would be more likely to believe the ever-present claims of sports proponents about how wonderful things like this are for the local economy.

One manufacturer has designed a vuvuzula which reportedly produces 20 fewer decibels.  While 100 dB dropped down to 80 dB will get you by in the workplace, it still ignores the fact that Soccer City in Johannesburg will hold up to 84,490 people for the World Cup this year.  Noise exposure is additive.  The end result of 20,000 (or more) people blowing is going to be far above 80 dB even with the new gadgets.

Picture of warning symbol on vuvuzula

One of these things turned up at the Riverview last week during the US : Slovenia game.  With the theater at almost capacity (I'd guess 90% of 700 person capacity), the vuvuzula was surprisingly loud.  Everyone turned around at the first blast and immediately knew what it was without seeing it.  One of them was a nice, if loud, addition to the game since it was only blown about a dozen times in short blasts.  In a really large movie theater, one was enough for me sitting at least 20 yards away.  I think it was at the back of the theater and I was sitting almost down front.

Last Sunday at the Germany : England game, someone brought a small (18") version to a restaurant.  It was an unholy racket.  Luckily he only blew it about 3-4 times before the game started.  The restaurant, needless to say, was much smaller than a movie theater.

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