Hearing Conservation Program
This hearing conservation program applies to those employees who are exposed to noise levels that equal or exceed an 8-hour time-weighted average (TWA) sound level of 85 decibels (dB). Noise exposures should be computed in accordance with WAC 296-817-300, Appendix R-9, without regard to the fact that personal protective equipment may reduce employee noise exposure.
The following examples are typical of high noise level environments:
When reasonable information indicates that any employee’s exposure may equal or exceed an 8-hour time-weighted average of 85 dBA, Seattle University must obtain individual or representative exposure measurements for the employees who may be exposed at or above that level. If you suspect that your work environment exceeds 85 dBA, please contact the Environmental Health & Safety Coordinator for assistance in obtaining exposure measurements.
Where circumstances such as high worker mobility, significant variations in sound level, or a significant component of impulse noise exist, we will use representative personal sampling unless area sampling will produce the same results.
Monitoring must be repeated whenever a change in production, process, equipment or controls increases noise exposures to the extent that:
The supervisor or the Environmental Health & Safety Coordinator will notify each affected employee when the results of the monitoring show that they are being exposed to an 8-hour time-weighted average of 85 dBA or greater.
The university will provide effected employees or their representatives with an opportunity to observe any measurements of employee noise exposure.
All employees whose exposures equal or exceed an 8-hour time-weighted average (TWA) of 85 dBA will be tested annually. The program will be provided at no cost to employees and may utilize an outside source to perform the actual tests.
Audiometric tests will be performed by a licensed or certified audiologist, otolaryngologist, or other qualified physician, or by a technician who is certified by the council of accreditation in occupational hearing conservation.
The first test establishes a valid baseline audiogram for each effected employee. The baseline audiogram will be used to compare subsequent audiograms.
Testing to establish a baseline audiogram will be preceded by at least 14 hours without exposure to workplace noise. This may be accomplished by use of hearing protectors. However, the supervisor must notify employees of the need to avoid high levels of non-occupational noise exposure during the 14-hour period immediately preceding the audiometric examination.
New audiograms will need to be obtained annually for each affected employee. Annual audiometric testing may be conducted at any time during the work shift. Employees must avoid noise for 14 hours preceding the test.
Annual audiograms will be compared to each employee’s baseline audiogram to determine if a standard threshold shift has occurred. A certified audiometric technician will make this comparison.
If the annual audiogram indicates that an employee has suffered a standard threshold shift, the university may obtain a retest within 30 days and consider the results of the retest as the annual audiogram.
An audiologist, otolaryngologist or other qualified physician will review audiograms that indicate a standard threshold shift to determine whether there is need for further evaluation.
Each employee will be informed of the results of his/her audiometric test and whether or not there has been a hearing level decrease or improvement since his/her previous test.
If a comparison of the annual audiogram to the baseline audiogram indicates a standard threshold shift, the Environmental Health & Safety Coordinator and the supervisor will ensure that the following steps are taken:
An annual audiogram may be substituted for the baseline audiogram when, in the judgment of the audiologist, otolaryngologist or other qualified physician who is evaluating the audiogram:
Those conducting all audiometric tests must assure the university that the tests meet the requirements of WAC 296-817-400.
Administrative or engineering controls have been and will continue to be explored for those employees whose exposures equal or exceed an 8-hour time-weighted average of 85 dBA. Suggestions to the Environmental Health & Safety Coordinator are welcome.
The university will supply and replace hearing protectors for all employees exposed to a time-weighted average of 85 dBA or greater.
Supervisors will ensure that hearing protectors are worn:
Employees may select their hearing protectors from at least two different types (i.e. molded, self-molded, custom molded, or ear muffs) of suitable hearing protectors provided by the university.
The supervisor must provide training in the use and care of all hearing protectors provided to employees. The supervisor must also ensure proper initial fitting and supervise the correct use of all hearing protectors. Contact the Environmental Health & Safety Coordinator for assistance.
The supervisor must evaluate hearing protector effectiveness for the specific noise environments in which the protector will be used. The most convenient method to use is the Noise Reduction Rating (NRR) that is listed on the hearing protector package. One common method of using the NRR to determine whether a particular hearing protector provides adequate protection within a given exposure environment, is the following:
Hearing protectors must lower employee exposure to less than 85 dBA.
The adequacy of hearing protector attenuation must be re-evaluated whenever employee noise exposures increase to the extent that the hearing protectors provided may no longer provide adequate attenuation. The supervisor will provide more effective hearing protectors where necessary.
All employees who are exposed to noise at or above an 8-hour TWA of 85 dBA will receive training at the time of the annual hearing test. In most cases, the person who performs audiometric tests will also provide the required training. Supervisors of employees who must obtain a hearing test outside of the scheduled group hearing test program may need to provide training themselves. The Environmental Health & Safety Coordinator may assist with arranging training.
Each employee will be informed of the following:
A copy of the Hearing Protection Standard and university program is available and can be obtained from the Environmental Health & Safety Coordinator, safety website, or your supervisor.
Signs must be posted at entrances to or on the periphery of all well-defined work areas in which employees may be exposed at or above 115 dBA. Warning signs must clearly indicate that the area is a high noise area and that hearing protectors are required.
The university will maintain an accurate record of all employee exposure measurements required by this section.
The Environmental Health & Safety office will retain a legible copy of all employee audiograms. This record will include:
The university will retain records required in this section for at least the following periods:
All records required by this section shall be provided upon request to employees, former employees, representatives designated by the individual employee, and the director. The provisions of WAC 296-62-052 apply to access to records under this section.
Impulsive or Impact Noise: Noise levels that involve maxima at intervals greater than one second. Where the intervals are less than one second, the noise levels shall be considered continuous.
Noise dose: The ratio, expressed as a percentage, of (a) the time integral, over a stated time or event, of the 0.6 power of the measured SLOW exponential time-averaged, squared A-weighted sound pressure and (b) the product of the criterion duration (8 hours) and the 0.6 power of the squared sound pressure corresponding to the criterion sound level (90 dB).
Standard threshold shift: A hearing level change, relative to the baseline audiogram, of an average of 10 dB or more at 2000, 3000, and 4000 Hz in either ear.
Time-weighted average sound level: That sound level, which if constant over an 8-hour period, would result in the same noise dose as if measured in the time varying noise level environment.