THE incidence of noise induced hearing loss is as high as 60% in noisy workplaces. Brad Witt calls for a new approach by safety professionals, looking beyond traditional Sound Level Conversion class ratings in protective equipment to consider the human factors.
"IN spite of growing awareness of hearing loss and increased efforts to combat it, the incidence of noise induced hearing loss among industrial workers continues to rise," says Brad Witt, Audiology and Regulatory Affairs Manager for the Hearing Safety GroupBacou-Dalloz .
He cites a study of the Australian construction industry (Milhinch, Dineen & Doyle, 1997) that has shown the incidence of noise induced hearing loss to be as high as 60% in noisy workplaces.
Witt calls for a new approach by safety professionals, looking beyond traditional Sound Level Conversion class ratings in protective equipment to consider the human factors that undermine hearing conservation efforts, he says, and look at new technologies now becoming available.
"By gaining a better understanding of how workers view noise, their hearing and hearing protection devices--as well as how they actually use safety protection tools on the job-safety professionals can make better purchasing choices and help reduce the likelihood of continued noise-induced hearing loss incidents." He advocates an approach based on what he calls the "four C's--Caring, Comfort, Convenience, and Communication."
The first step, Witt says, is to help workers understand and care about hearing protection. "For many workers, hearing loss is a remote threat at best," he says. "Many people don't realise that the impact of hazardous noise is cumulative, and even brief periods without protection can generate real, lasting hearing loss. This requires an educational effort."
Safety officers must also make sure hearing protection devices are comfortable, convenient to use, and fitted correctly. "Our research clearly indicates that comfort is a prime driver of how diligently people will wear hearing protection."
Witt cites several new product technologies that enhance comfort and usability, including a new Matrix earplug from Howard Leight, which utilises high-tech, dual-density TPE foam to create a smooth-skinned cylinder. The earplugs not only fit different ear canal sizes more comfortably, they require no rolling to insert and provide instant protection upon proper insertion.
Another new technology used in a Howard Leight product called SmartFit allows the earplug to change shape as it warms to body temperature and conform to the contours of the wearer's ear canal for a more personalised fit.
New comfort and usability features extend to earmuff products, as well. Witt points to new Bilsom headband designs, which include soft, ventilated inner surfaces to prevent heat and perspiration buildup; adjustable outer headbands to ensure a comfortable fit and minimise slippage; and unique multiple position headbands that allow the earmuff to be worn with other personal protection equipment.
Softer ear cushions also promote increased comfort and create a better seal around the ear, while a snap-in design allows easy replacement, extending the life of the earmuff for maximum usability.
But the biggest need Witt sees is to enhance a worker's ability to communicate while wearing hearing protection on the job. "It's ironic," he says, "that in order to protect workers from permanent hearing loss, we subject them to temporary hearing loss."
Witt cites a growing body of research that suggests links between the inability to hear while wearing hearing protection and industrial accidents. In addition, workers who cannot communicate easily feel more isolated on the job and are less likely to be contented and productive.
A number of new products are available to facilitate protected communication, Witt points out, using both passive and electronic solutions. One new technology resulting from advanced materials research is called 'uniform attenuation.'
This uniform attenuation profile blocks harmful noise while allowing other sounds, like human voices and alarms, to be heard more naturally. Several products are now on the market with this capability, including the Matrix earplugs noted above, and the newly redesigned Clarity line of earmuffs from Bilsom.
Also of value in protecting against what Witt calls "the dangers of overprotection," are hearing devices that are available in a variety of class ratings. These allow users to target the level of attenuation to the needs of their work environment, enhancing both their ability to communicate on the job and their psychological well-being, as well as saving resources.
"After all," says Witt, "we are dealing with human beings. If we are to reverse the growing incidence of noise induced hearing loss, we need to consider the human elements of the equation, and choose products and tactics which will allow us to address those elements successfully."
Since its beginnings as a one-man operation more than 30 years ago, Howard Leight Industries has grown into one of the largest manufacturers of in-ear hearing protection in the industrial market and is widely recognised as an innovator in protection and fit. Since 2001 Howard Leight has been a part of the Bacou-Dalloz Hearing Safety Group.