By GREGG WYCHERLEY
It's the way farmers once kept track of their dairy cows ... and it's Waikato's secret rugby weapon.
Well, no ... not secret. The clanging cowbells used by fanatical Mooloo rugby supporters to urge their team on make far too much noise to be rated a secret.
Visitors to Waikato Stadium for tonight's NPC final between Waikato and Auckland will be subjected to bursts of cowbell-ringing of close to 110 decibels - and that's from just one bell.
Noise testing on the standard Mooloo bell shows peak levels of 106 decibels. A big home-made bell can reach an ear-shattering 109.8 decibels.
Add in thousands more bells, a lot of screaming, cheering and yelling, and the result is a maelstrom of noise guaranteed to leave the ears ringing.
The Waikato bell-ringers create the kind of racket normally experienced by workers in sheet-metal shops or on large printing presses.
One Mooloo bell is louder than a heavy truck from 6m away, or a pneumatic jackhammer smashing concrete.
It is louder than the platform of an underground train station at maximum level, and much noisier than the average construction site.
Don Williams and Murray Broom, from Opus International Consultants, who did the noise tests, had temporary tinnitus after the tests.
Tinnitus? Ringing in the ears, in layman's language.
Mr Williams said the bells were, in his professional opinion, "bloody loud".
"If you had someone ringing that thing behind you, I think you'd want to move."
He said decibel levels increased at an exponential rate.
That means a 106 decibel Mooloo bell is much louder than the 90 decibel pneumatic drill on a building site, but nowhere near the 140 decibels created by a military jet taking off.
Labour Department guidelines class noise of more than 120 decibels as intolerable and likely to cause hearing damage.
The Mooloo bell output is definitely loud enough to cause ringing ears and hearing loss.
But the damage is likely to be temporary if the noise is not sustained.
Any noise that gets up around 110 decibels is potentially dangerous, says Auckland ear, nose and throat surgeon Dr Ron Goodey.
"But for serious damage to occur, the noise has to be confined or sustained for some time," he said.
"I wouldn't want to have one rung anywhere near my head or ears, but because the sound is intermittent you'd probably get away with it.
"Bells wouldn't stop me going to the game, put it that way."
International studies recommend that people exposed to noise levels around 110 decibels, such as from a chainsaw, should limit that exposure to 30 minutes or wear earplugs.
But while the damage done to the ears can be tested, the effect on the morale of visiting teams can only be guessed at.
Maybe Blair Feeney's atrocious goalkicking effort during Otago's semifinal loss at Waikato last weekend was clanger induced.
And Waikato captain Deon Muir rubs salt into the wound by presenting bells to opposing captains after their games.
The marketing manager of the Waikato Rugby Union, Pat Mellsop, said the $20 Mooloo bells were a key weapon in the dedicated supporter's armoury.
They were imported because the local version was more expensive and not always available.
"It's rugged, it's solid, it makes a good sound, it's got the colours in the right order.
"For 20 bucks it's a great deal."
He estimates about one in five of any Waikato crowd is packing a bell.
Over the past three years nearly 700 children have bought them for the $10 it costs to join the Mooloo Kids Club, so the trend is not likely to slow.
With a perfect record at home during the NPC competition so far, Waikato's Mooloo bells are tolling success.
NPC schedule/scoreboard
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