Protecting Workers from Hearing Lose Due to Excessive Noise Levels
Clark Seif Clark conducts industrial hygiene surveys for occupational exposures to noise and provides employer compliance consulting services.
Chatsworth, CA -- Worker exposure to environmental noise is sometimes difficult to avoid. However, understanding noise levels employees are exposed to is not difficult. The most significant effect of high noise levels is permanent hearing loss. Hearing loss and the degree of loss are directly related to the total energy impacting the ears. Often, the total energy at a noise source cannot be changed. In these cases, a way to keep the full force of that energy from striking the ear needs to be found.
The Occupational Safety and Health Administration (OSHA) limits noise exposure to a 90 dBA time weighted average for an 8 hour workday. However, individuals are all different in terms of whether the 90 dBA limit is enough to protect them. In fact, the National Institute of Occupational Safety and Health (NIOSH) believes that limiting exposure to 90 dBA for an 8 hour workday will still result in a 25% excess risk of a material hearing loss. The excess risk is risk of losses in the population that occur in addition to hearing loss caused by normal aging or other non-noise related causes.
So, what is too loud? If one needs to raise their voice to talk to someone who is less than 3 feet away, it is likely too loud.
“Whether a worker has to raise their voice or not to communicate is not a scientific assessment,” said William Jones, CIH, CSP, CPE and Vice President of Industrial Hygiene at Clark Seif Clark. “A more complete assessment can be easily done through a combination of personal exposure dose measurements, sound measurements at the source and area sound measurements.”
If measurements indicate that the limit is exceeded, reducing the total energy reaching the ear can be done as follows:
- Engineer the noise out through replacement of equipment, using barriers or sound absorption, moving the noisy operation farther away from personnel or enclosing the operation
- Use administrative controls such as limiting exposure time by rotating personnel in and out of loud areas, conducting maintenance more frequently such as changing band saw blades or lubricating machinery components more often
- Use personal protective equipment (PPE) such as ear muffs or plugs.
If there are noise exposures of 85 dBA or above (whether or not PPE is worn), OSHA requires a hearing conservation program. Hearing conservation requirements are detailed and specific. A hearing conservation program requires:
- Exposure monitoring (initially and when there are changes in the work environment)
- Audiometric testing (hearing test of exposed personnel)
- Hearing protection with known (i.e. tested) effectiveness
- Formal training program
- Record keeping
Clark Seif Clark’s experienced industrial hygienists can conduct noise studies, help write a customized hearing conservation program and even assist with written employee notifications of monitoring results. To learn more about this or other occupational, industrial hygiene, indoor air quality, environmental, health and safety testing services, please visit www.csceng.com, email firstname.lastname@example.org or call (800) 807-1118.