Q. We have a lot of machinery that give off noise. How do we know if we need some type of hearing loss program?
A. The Occupational Safety and Health Administration (OSHA) protects workers in the workplace from many hazards. One of the hazards that is often overlooked by employers is noise exposure, because you cannot see it. However, long-term exposure to loud or high pitched noise can cause irreversible damage to employees, so OSHA created the Occupational Noise Exposure standard found at 29 CFR 1910.95.
Without getting into any numbers yet, some good indicators that noise levels in your workplace have exceeded “acceptable” limits include, but are not limited to, the following:
- It is necessary to shout in order to hear three feet away,
- Noise levels seem louder than busy city traffic,
- After exposure, you notice muffling or softening of sounds,
- After work shift ends, it is necessary to increase the volume of the radio or TV to a level too loud for others, or
- You experience tinnitus (a loud ringing or buzzing noise that continues after the noise stops).
OSHA requires noise exposure to be measured in decibels according to the “A scale” (dBA). The dBA scale most closely mimics the scale of human hearing and is measured with a device that has a damper on the meter needle. This ensures that readings are averaged out when sound levels are uneven.
Depending on how many hours an employee is exposed to a given noise, they will have different permissible exposure limits (PEL). Regardless of PELs, employers must administer a hearing conservation program whenever employee noise exposures equal or exceed the “action level.” The action level is an 8-hour, time-weighted average (TWA) constant sound level of 85 dBA, or equivalent dose. [29 CFR 1910.95(c)]
The TWA is the daily “amount” of noise that the employee is exposed to, not a single exposure, and is affected by how loud the noise is, how close the employee is to the source of the noise, and how long the employee is exposed. It is important to note that this noise level should be calculated without regard to protection offered by personal protective equipment (such as ear plugs or ear muffs).
The regulations for PELs and measuring TWAs can be found in Appendix A
of 29 CFR 1910.95
If it is determined that you need a hearing conservation program, it must include the following elements:
- Employee monitoring,
- Employee notifications,
- An audiometric testing program,
- Hearing protectors,
- Employee access to information, and
If you or anyone at your facility requires more information on OSHA’s standards for noise exposure, we recommend taking Lion’s Hearing Conservation
online training program