SoundIntensity of Sound |
Are there federal standards for using hearing protection? |
After leaving loud rock concerts, many concert-goers often complain of ringing in their ears. The ringing sound is a result of the damage to the cilia by the intense sounds. Usually the ringing is gone the day after the concert, but permanent damage has already been done, because those hair cells will not recover. Although the effects of such hearing loss may take many years and repeated exposure to loud sounds to become apparent, they can nonetheless become very devastating.
Federal regulations mandating the use of hearing protection in the workplace state that if an employee works for eight hours in an environment in which the average noise level is above 90 decibels, the employer is required to provide free hearing protection to those employees. For example, many high school and college students work for landscapers in the summer. Since the average decibel level for a lawnmower is about 100 decibels, and if the employees are working for eight or more hours per day, free ear plugs or ear muffs must be provided to the employees.