Occupational Safety and Health Association

Although any worker can be at risk for noise-induced hearing loss in the workplace, those in certain industries typically have higher exposures to this workplace menace. Industries with significant numbers of at-risk workers include agriculture, mining, construction, manufacturing and utilities, transportation, and the military. For example, industry-specific studies compiled by OSHA show that:

• 44 percent of carpenters and 48 percent of plumbers reported that they had a perceived hearing loss.
• 49 percent of male, metal/nonmetal miners will have a hearing impairment by age 50 (versus nine percent of the general population), rising to 70 percent by age 60.

Noise Numbers
OSHA warns that continued exposure to more than 85 decibels (dBA) of noise may cause gradual but permanent damage to hearing. Therefore, federal regulations require that, when engineering controls and/or administrative controls cannot reduce noise levels to an eight-hour time-weighted average (TWA) level of less than 85 dBA, a hearing protection (conservation) program must be established. According to the American Speech-Language-Hearing Association, this five-phase OSHA program includes:

1. Noise Monitoring: Sound levels must be measured. Results of the test are used to decide a) which employees need to be in the hearing conservation program; b) whether hearing protection devices must be used or be available on an optional basis; c) which hearing protection devices are appropriate for different noise levels of the facility.
2. Audiometric (Hearing) Testing: All employees in a hearing conservation program must have baseline and annual hearing tests. Baseline audiometric testing helps the employer determine the presence or absence of a pre-existing hearing loss and may assist the employer in determining job placement for the employee. Annual audiometric testing assesses the effectiveness of the hearing conservation program. Each annual audiometric test is compared with the employee's baseline test to determine if there has been any deterioration in the employee's hearing.
3. Employee Training: Employees involved in a hearing conservation program must receive annual education and training on a) the effects of noise on hearing; b) hearing protection devices (their availability to employees, their advantages and disadvantages, techniques for proper selection, fit, use, and care); c) the purpose and procedures of audiometric testing.
4. Hearing Protectors: Hearing protection devices should be made available to all employees; mandatory versus optional use is determined by noise exposure monitoring. Hearing protection devices must be worn by employees whose eight-hour TWA is 90 dBA or greater and by employees whose TWAs are between 85-90 dBA if they display standard threshold shifts in hearing levels. A standard threshold shift is defined by OSHA as "a change in hearing threshold relative to the baseline audiogram of 10dB or more for the frequencies 2000, 3000, and 4000 Hz in either ear." Hearing protection devices must meet sound reduction levels required by OSHA.
5. Recordkeeping: Sound measurement results, equipment calibration results, and audiometric test records of employees must be maintained for specific periods of time.

Change Is Coming
OSHA's workplace noise standards specify that "feasible administrative or engineering controls" must be used to reduce noise to acceptable levels; personal protective equipment, such as ear plugs and ear muffs, must be used only as supplements when administrative or engineering controls are not completely effective.

OSHA notes that engineering and administrative controls are generally more effective than personal protective equipment. However, under OSHA's current enforcement policy, the agency may issue citations for failure to use engineering and administrative controls only when they cost less than a hearing conservation program or when such equipment is ineffective.

OSHA wants to change that. It is proposing to issue an interpretation of the term "feasible administrative or engineering controls" as used in the general industry and construction occupational noise exposure standards and to amend its current enforcement policy to reflect the interpretation. OSHA is seeking comments on this issue through Dec. 19, 2010, at its web site http://www.regulations.gov