| OSHA’s
Hearing Conservation Requirements
Whenever feasible, employers are required to reduce the noise at the
source through engineering solutions. When this is not possible or
economically feasible it is acceptable to use hearing protection as a
temporary solution. The term hearing conservation as defined by OSHA
includes the following aspects, which the employer is responsible to carry
out:
- Monitoring of the noise environment. If the TWA (Time Weighted
Average) noise level is exceeding 85 dB(A), a hearing conservation
program is required.
- Selecting hearing protection devices appropriate for the environment
or environments at hand. Several different types of hearing protectors
are required to be offered to the employees, in order to introduce a
level of personal choice. The employer is responsible to pay for the
original equipment as well as replacements. The employees are required
to use the hearing protection, and the employer is responsible for the
enforcement.
- Training and educating employees in the proper use of hearing
protection, the importance of full time use of hearing protectors when
working in a noisy environment. Education and training is considered
an essential and ongoing activity.
- Establishing a baseline audiogram for each noise exposed employee,
and annual hearing tests thereafter in order to monitor the hearing
health of the employees. Have the audiograms evaluated by an
audiologist
or physician.
Take corrective action when it is concluded that a noise induced
hearing damage is occurring. Corrective action can entail further
education and training in the use and importance of full time use of
hearing protection. Seeking the use of hearing protectors better suited
to the environment and the individual. Using, what is called
administrative controls, which simply means to reduce the exposure time
for the employee in question. If these efforts fail, an employee may be
transferred to a quieter job.
The above summary of OSHA’s hearing conservation requirements is not
intended to be complete. The
complete regulation (29CFR-1910.95) is available on the internet.
You can access it from Elvex website, by clicking on this link.
Facts about noise # 5: Conflicting
information about how to use the NRR
Check out the NIOSH noise meter! |
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OSHA’s Permissible Noise Exposure
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- 90 dB
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- 92 dB
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- 95 dB
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- 97 dB
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- 100 dB
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- 102 dB
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- 105 dB
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- 110 dB
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- 115 dB
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- 8.0 hours
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- 6.0 hours
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- 4.0 hours
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- 3.0 hours
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- 2.0 hours
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- 1.5 hours
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- 1.0 hours
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- 30 minutes
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- 15 minutes
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- How to use the NRR
When the dB(C) noise level is known, you don‘t have to adjust
the NRR:
Noise level at ear: dB(C) - NRR =< 90 dB (*)
When the noise level is known in dB(A) the NRR must be reduced
by 7 dB:
Noise level at ear: dB(A) - [NRR –7] =< 90 dB (*)
(*) If a threshold shift (hearing damage) exists the noise level
at the ear must be 85 dB or less.
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- Overprotection can be a problem!
Selecting a high NRR hearing protector for an environment where
only good high frequency attenuation is needed, will lead to
unnecessary insulation and communications difficulties.
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- Field
Attenuation
-
- It has been proven in many studies that hearing protectors are
not as effective in the field, as the laboratory numbers
indicate. In the laboratory the hearing protectors are used
correctly, while in many field situations they are not.
Employees are either not trained or motivated to make the effort
to use the protectors in a correct way. NIOSH recommends a
de-rating of 50-70% for earplugs and 25% for earmuffs.
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- Is Your
Program Working?
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- How do you know if your hearing conservation program is
working? The answer is in your annual audiograms. If they do not
show any new noise induced hearing damage, your program is
working.
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Facts About Noise #7