Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: MONDAY, March 5, 1990 TAG: 9003023567
SECTION: EDITORIAL PAGE: A-11 EDITION: METRO
SOURCE: JOHN G. CASALI
DATELINE: LENGTH: Long
From my vantage point midway up in the stands, approximately 100 feet straight across from the junked cars at track center, I could fully appreciate the overwhelming size and sound of these trucks. The din produced by the unmuffled, supercharged, big-block V-8 engines in the enclosed arena was unbelievable. After donning my foam earplugs plus a heavy-duty earmuff, I proceeded to obtain noise-level readings as the trucks entered the arena in pairs and raced side-by-side over the flattened cars.
The decibel (dBA) meter confirmed the obvious; in a word, these vehicles are loud, very loud. The races were completed in slightly more than two hours, with a number of "quiet" periods interspersed throughout, including between-race breaks, an intermission and children's attractions. Even so, the average sound level for the two-hour event was 97 dBA. (By comparison, a jackhammer produces about 95 to 100 dBA and a vacuum cleaner about 70 to 75). During almost every match race, average noise levels exceeded 100 dBA. Under hard acceleration over the ramps, continuous noise levels frequently topped 122 dBA, with noise peaks of up to 139 dBA (levels near those of a jet taking off at more than 100 feet away).
What is the problem with this noise? After all, the engine roar seems to heighten the excitement and reinforces the staggering power of these giant trucks. Unfortunately, spectators are exposed to sound levels uncommon to everyday life, many of which are potentially hazardous to their hearing. For example, the noise of upwards of 120 dBA during acceleration, if encountered frequently enough, is sufficient to induce hearing loss. (In comparison, under federal regulations aimed at preventing hearing loss in the work-place setting, the Occupational Safety and Health Administration prohibits continuous noise levels of above 115 dBA for any duration during the workday.) While certain noise-sensitive individuals who attend monster-truck clashes (or similar indoor motorsport events) probably have some risk of incurring hearing damage, very avid spectators, track personnel, drivers and mechanics should exercise extra precaution due to the large number of their exposures.
Furthermore, if individuals participate in other loud recreational events such as target shooting or rock concerts, or have a noisy occupation, the overall hearing risk increases. A properly fitted noise-attenuating earplug or earmuff should be standard gear for even the most infrequent monster-truck spectator or participant. At the Feb. 18 event, only a minority of the audience members wore hearing protectors, and many of these used only cotton, which provides little or no protection.
No matter what the type of noise, if exposures are too intense for too long, irrecoverable hearing loss can occur due to delicate nerve structure damage. Impairment is permanent, and usually first affects one's ability to hear high-frequency sounds, such as birds singing or electronic wristwatch alarms, followed by a loss of speech understanding and the accompanying social handicap. No one really ever "gets used to" loud noise, though this may seem to be the case. When this feeling occurs, the ear probably has lost some of its sensitivity, providing a warning of sorts that damage may be impending. Other warning signs include "ringing in the ears," called tinnitus, and the sensation of sounds being "muffled."
The recent article indicated that Allan Goss (events manager for TNT motorsports) said the noise didn't bother him anyway because he is nearly deaf in one ear. But since hearing loss is progressive with continued noise exposure, he risks losing more hearing in his good and his bad ear!
Though we attend spectator events such as monster-truck and similar motorsport races by choice, can't something be done to alleviate the possible risks to our hearing? Most certainly, and without great expense.
Because many individuals are simply unaware of the health threat that high-intensity noise poses, conspicuous warnings of the potential danger of the event's noise should be posted at the arena entryways. The spectator's primary defense is to wear hearing protectors, such as the earplugs available at the truck clash for $1 per pair. But why should spectators have to pay extra to be protected from the noise generated by the very event they've paid to see? In the spirit of promoting safety (which is evident in the monster-truck crash safeguards), event promoters could provide free disposable earplugs to spectators entering the arena. With high-quality earplugs available in bulk at 15 to 20 cents per pair, and the ticket price $10, this would represent a small investment for safety.
Couldn't the monster-truck engines simply be muffled? No, says Goss in the article. "Any kind of exhaust system reduces horsepower. Besides, these engines would blow a muffler right off." Not exactly. With properly engineered mufflers designed for high-performance engines, power loss can be avoided. (But with some 1,500 horsepower on tap, there's certainly a bit of horsepower available to lose.) Of course, the natural argument is that quieting the monster engines would reduce the excitement. But 95 dBA is still exciting (and considerably less risky to our ears than 120).
Adding it all up, the Monster Truck Clash was action-packed and lots of fun for the spectators. The drivers and their vehicles put on quite a show, leaving a lasting impression on the audience. Let's just urge the organizers to take a few steps to insure that next time, there's no chance for a lasting impression on our hearing.
by CNB