| Safety Instruction 44 |
Hearing Conservation Program and Noise Control
Plan
|
Update
09/11/2007
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A. POLICY STATEMENT.
It is the policy
of Oregon State University (OSU) to protect employee hearing and effectively
manage or eliminate hazardous noise exposures. In those areas where engineering
controls cannot reduce noise below harmful levels or until engineering controls
can be implemented, employees will take part in a Hearing Conservation Program
(HCP). Environmental Health & Safety (EH&S) has been designated to administer
the overall HCP.
Employees are required to fully participate
in the program outlined in this policy as a condition of employment. Employees
must wear the provided ear protection devices when working in posted noise areas.
Each employee exposed to sound levels in excess of 85 dBA, in the normal responsibilities
of their position, will be:
- Given a baseline audiogram prior to assignment, and a follow-up audiogram after one year, provided at no cost to the employee.
- Provided with a choice of suitable hearing protectors,
fitted, and encouraged to use them.
- Wearing of ear protection is mandatory for employees
working in areas where noise exposure exceeds 85 dBA (8hr TWA).
- Notified of any abnormal audiogram indicating a standard
threshold shift.
- Provided annual training and information.
Each employee exposed to 85 dbA or greater as an eight-hour time-weighted average will be:
- Notified of noise exposure monitoring results when their
exposure is 85 dBA or greater (8hr TWA).
- Notified of any abnormal audiogram indicating a standard
threshold shift.
- Provided with annual audiograms at no cost to the employee.
- Required to wear hearing protection in environments with noise > 85 dBA, regardless of the duration of exposure.
B. RESPONSIBILITIES.
1. EH&S will:
- Perform or coordinate noise exposure monitoring.
- Identify employees to be included in the HCP.
- Supervise hearing protector selection, and provide
assistance for employees who have problems with hearing protector fit.
- Develop policies relating to the use of hearing
protectors.
- Supervise employee training programs.
- Coordinate and supervise recordkeeping.
- Evaluate overall program at least annually.
- Review suggested options for noise control, and
work with the Purchasing department to ensure noise levels are considered
for new equipment purchases.
2. Supervisors will
- Monitor and ensure the wearing of hearing protection
in all posted areas.
- Wear and maintain hearing protection in all posted areas.
- Check the fit and condition of hearing protection and
ensure replacement when necessary.
- Ensure workers attend safety meetings/talks on hearing
protection.
- Ensure workers attend annual audiometric tests.
- Notify EH&S if any additional high noise areas are
suspected.
- Contact EH&S if new procedures are implemented which
may affect noise levels.
3. Workers will:
- Wear and maintain hearing protection in all posted areas.
- Attend safety meetings/talks on hearing protection.
- Participate in annual audiometric testing.
- Bring any hearing protection or noise related problems
to the attention of management.
- Report to their supervisor any changing conditions which
may impact personnel noise exposures.
4. Student Health Services- Occupational
Medicine group will:
- Perform audiometric testing for employees on a fee-for-service
basis.
- Keep occupational medicine records for employees in the
HCP.
- Coordinate with other occupational medicine providers
for employees in remote sites for testing and recordkeeping.
C. PROGRAM REQUIREMENTS
1. Noise Monitoring.
- Noise levels in some areas at OSU exceed 85 dBA. The
noise exposure levels for areas and sources that have been measured are available
through EH&S.
- Additional noise monitoring will be conducted whenever
employee exposures are expected to change (equipment changes, plant modifications,
engineering control installations, etc.). For employees having fixed working
locations near steady and continuously operating noise sources, a sound level
measurement made for a representative period at the employee’s position will
indicate his or her exposure level. The measurement interval should be of
sufficient duration to encompass a reasonable number of operating cycles for
the task or machinery being considered.
- Where work activities and resulting noise levels are
variable, and particularly where individuals do not have fixed working locations,
employee exposure levels are most accurately determined by means of a personal
noise dosimeter.
- Affected employees or employee representatives will be
notified of planned monitoring by EH&S and permitted to observe. Employees
will also be notified of monitoring results.
- Employees in the following areas or performing the following
jobs will be included in the Hearing Conservation Program.
Carpentry
– power tools |
Forestry Operation - Chain Saws |
Emergency
power generators - maintenance |
|
| Landscape – power tools |
|
2. Audiometric Testing.
- Baseline and one follow-up audiometric testing will be performed for all employees working in areas with sound levels in excess of 85 dBA.
- Subsequent annual audiometric testing will be
performed for employees with Time Weighted Average exposures which exceed
85 dBA.
- OSU Student Health Services (SHS) Occupational
Medicine will perform audiometric evaluations unless previous arrangements have been made for equivalent testing, especially in remote sites such as experiment station and extension facilities.
- Audiometric
test questionnaire and Instructions
- Audiometric tests shall be performed by a licensed
or certified audiologist, otolaryngologist, or other physician, or by a technician
who is certified by the Council of Accreditation in Occupational Hearing Conservation.
A technician who performs audiometric tests must be responsible to an audiologist,
otolaryngologist or physician.
- Audiometric
testing results provided by SHS will be reviewed to ensure the appropriate
follow-up actions are taken. If a Standard Threshold Shift (STS) is identified
(an average shift in either ear of 10 dB or more at 2,000, 3,000 or 4,000
Hz), the employee will be re-tested within 30 days, and the results of the
re-test will be used as the annual audiogram.
- If STS is indicated, the employee will:
- be notified of the threshold shift within 21 days
of this determination.
- be informed of the need for further evaluation or
retesting if a medical problem is suspected.
- be required to wear hearing protection if exposures
equal or exceed 85 dBA.
- be refitted or retrained in the use of hearing protection.
- be referred for additional audiology or medical
testing, if appropriate, and informed of the need for this testing.
3. Hearing Protection.
- Until engineering and/or administrative controls
reduce the amount of noise exposure to or below the allowed limits, appropriate
personal hearing protective devices are made available and issued to employees
working in jobs or areas where exposure may exceed a TWA of 85 dBA. It is
recognized that the use of these devices is considered a temporary solution
to the problem of overexposure until feasible controls are provided. The wearing
of hearing protection in the following areas or jobs is mandatory:
Wood shops |
Air powered tools |
Landscape management – power tools |
|
Gas powered hand tools |
|
- In addition, hearing protection is mandatory for
any employee who has incurred a standard threshold shift as reported by EH&S.
All supervisors will properly enforce hearing protection requirements. Continuing
failure of an employee to properly wear the protection provided could result
in the termination of employment with the company.
- All visitors, management or employees who may enter
or pass through a hearing protection required area will also be expected to
wear hearing protection.
- A variety of hearing protection options, including
ear plugs and muffs, will be made available so that employees can choose the
type which is most comfortable for them.
- The procedure in Appendix A will be used
to ensure that selected hearing protection devices reduce noise exposures
to an acceptable level.
4. Noise Signs.
- All work areas where noise exposures may exceed
85 dBA will be posted with noise warning signs at entrances to these areas.
All employees in the HCP will wear ear protection when working in posted areas.
All other employees or visitors passing through these areas will also be required
to wear hearing protection.
- Tools which generate sound levels in excess of
95 dBA will be labeled. Hearing protection must be used by operator when this
equipment is used. The following equipment should be labeled:
Circular
saws |
Chop (miter)
saws |
Chain
saws |
Air tools
– staplers, nailers, grinders |
Mowers |
|
Gas powered
hand tools |
|
5. Employee Training.
- Participation in an annual training program is required
for employees exposed to noise at or above 85 dBA. The training will include
information on:
- Purpose and use of hearing protectors, advantages
and disadvantages of various types.
- Instructions in selection, fitting, use and care
of hearing protectors.
- Purpose of audiometric testing and an explanation
of test procedures.
- Contents of OR-OSHA’s Occupational Noise Exposure
standard (29cfr 1910.95).
- A copy of the noise standard and the written training
and instructional materials are available to employees upon request.
- Records of training will be maintained.
6. Recordkeeping.
- Audiometric program records are maintained in the employee’s
personnel file and will be provided to employees upon request. Records applicable
to employee monitoring and exposure records will be retained as follows:
- Employee audiometric test records (baseline and
annual audiogram, retests, test room background levels, and audiometer
calibration records) are maintained for the duration of affected employees
employment plus 30 years.
- Noise exposure measurement records are maintained
for 30 years.
- Program audit records will be maintained for 3 years.
7. Program Evaluation.
- The success of the hearing conservation program
with regard to each individual employee is evaluated by comparing annual
audiograms to the baseline audiogram. This procedure, among others, helps
to determine the effectiveness of the hearing protection program, and, as
a result, ensures the protection of employees' hearing.
- EH&S is responsible for reviewing the recommendations
of the audiologist or physician.
- OSU
will make an effort to address employee concerns about hearing protection
fit, comfort, or overprotection. However, it is the responsibility of the
employee to bring those concerns to the attention of supervisors.
- If an employee experiences a STS, that employees’
workstation or work area will be specifically evaluated to determine if
feasible engineering controls can decrease the noise levels. A checklist
to be used is in Appendix B.
8. Engineering & Administrative
Controls.
- OSU recognizes the desirability of controlling
the existing noise levels by engineering and/or administrative controls.
Therefore, the feasibility of such controls is carefully considered including
possible redesign of existing machinery, the building of partial or total
enclosures, and other engineering noise control procedures for reducing
the existing noise levels.
- Due to the complexity of some machinery used at
OSU and in view of economic limitations, some noise levels cannot be reduced
to below acceptable limits. Within the limitation of work schedules and
employee skills, administrative controls have also been considered. On a
continuing basis, engineering and administrative controls will be considered
and implemented where feasible.
- OSU also recognizes the desirability of considering
noise levels prior to the purchase of new or rebuilt equipment. It is our
policy to evaluate noise levels prior to equipment purchase.
Appendix A – Computation
of Actual Noise Reduction Ratings (NRR)
- The degree of protection that a hearing protection
device provides is referred to as the Noise Reduction Rating or NRR. Because
the listed NRR is established for C-weighted noise measurements, and our
measurements have been collected using an A-scale, 7 dB will be subtracted
from the NRR to take this into account.
- NRRs for ear protection are established in laboratory
settings under ideal conditions, and it is unlikely that the noise reduction
in industrial areas will be as substantial as that recorded in the lab.
Because of these differences between laboratory and “real world” performance,
the following NIOSH derating scale will be used when calculating noise reduction:
Hearing
Protection Device |
Derating
scale |
Ear
muffs |
25%
reduction |
Formable
ear plugs |
25%
reduction |
All
other earplugs or semi-aural devices |
25%
reduction |
- Using this method, a formable earplug with a NRR of 30 dB actually
provides:
- 30 dB (listed NRR)
- 7 (A-scale to C-scale adjustment) = 23 dBA reduction - laboratory measurement
- 23 dBA x 75% = 17.3 dB of "real-world"
noise reduction.
- Products with the highest NRR are not always the best
choice for hearing protection. Too much noise reduction, when not necessary,
can lead to degradation of communication, especially in individuals who
have some degree of hearing loss.
- Communication problems associated with maximum
NRR devices may lead to accidents and poor employee acceptance of the hearing
conservation program.
- The following general guide to protection levels
will be used:
If the device reduces the noise
to: |
Then the protection is: |
> 85 dB |
Insufficient |
80 - 85 dB |
Acceptable |
75 - 80 dB |
Good |
70 - 75 dB |
Acceptable |
<70 dB |
Too high |
Appendix B – Employee Standard
Threshold Shift Checklist
The Employee
Standard Threshold Shift Checklist (PDF document) must be completed
whenever an employee has suffered a confirmed Significant Threshold Shift
(STS).
