When feasible, employers are required to use engineering solutions to reduce hazardous noise in the work environment. When an engineering solution is not possible or economically feasible, it is acceptable to use hearing protection as a temporary solution. The best hearing protector is the one that is comfortable and convenient and that the worker will wear every time they are in an environment with hazardous noise.
The following provides information on the different types of hearing protection devices:
Disposable formable plugs are made of a material that is designed to expand and conform to the shape of the wearer’s ear canal. They are rolled or compressed by the wearer prior to inserting it into the ear. It works best when the wearer creates a smooth tube thin enough to fit in the ear about half the length of the plug. These formable ear plugs can be for single use or reuse for up to a week. They are good for a variety of noise areas, but are not recommended for use in areas where workers’ hands can become contaminated with abrasive materials, dirt, or irritating or caustic substances since the plugs must be formed using the hands. Some individuals with small ear canals may have difficulty rolling the plugs small enough to make them fit; in these situations, a small-size, expandable plug can be used.
Pre-molded plugs are reusable and generally made from silicone, plastic, or rubber, and are available in several styles – as one-size-fits-all, sized, or custom molded. The plugs should seal the ear canal without being uncomfortable, which generally takes trial and error of the various styles and sizes. Advantages of pre-molded plugs are that they are relatively inexpensive, reusable, washable, and convenient to carry, and come in a variety of sizes – nearly everyone can find a plug that will be comfortable and effective. Unlike the disposable formable plugs, in dirty or dusty environments, a worker does not have to handle or roll the tips. These plugs are recommended for hearing protection where workers are exposed to high levels of noise. A critical user-tip about pre-molded plugs is that a worker may need a different size plug for each ear.
Canal caps are cone-shaped earplugs on a flexible plastic or metal band. The earplug tips may be molded by the user or be of a pre-molded material. The headbands provide a means to wear the device over the head, behind the neck, or under the chin. Some models have jointed bands, increasing the ability to properly seat the earplug. The main advantage canal caps offer is convenience. When it is quiet, workers can leave the band hanging around their necks and can quickly insert the plug tips when hazardous noise starts again; however, some workers find the pressure from the bands uncomfortable. In addition, not all canal caps have tips that adequately block all types of noise. Generally, the canal cap tips that resemble stand-alone earplugs seem to block the most noise. Canal caps are recommended for a variety of noisy locations, and especially for workers who are uncomfortable wearing plug-type protectors.
Earmuffs are available in active noise reduction (ANR), dielectric, and passive designs, and come in many models intended to fit most people. They work to block out noise by completely covering the outer ear. ANR earmuffs employ electronics to cancel low frequency noise and are recommended for locations with high level, severe noise. Dielectric earmuffs do not contain any metal parts and are recommended for work around high-voltage lines, power plants, utilities, and generating plants. Passive earmuffs allow desirable sounds (conversation) to reach the ear, and are recommended for impulse noise locations, rather than locations with sustained, high-noise levels. Some earmuffs also include electronic components to help users communicate or to block impulse noises.
Workers who have heavy beards or sideburns, or who wear glasses, may find it difficult to get good protection from earmuffs. Beards or sideburns, and the temples of eyeglasses, can break the seal that the earmuff cushions make around the ear; for such workers, earplugs are recommended. Other potential drawbacks of earmuffs are that they can be hot and heavy in some environments.
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