***This could be you . . .***

*A worker didn't think it was important to use hearing protection while
working with equipment that produced high levels of noise, so usually
"forgot" to wear any hearing protective devices. He eventually noticed
that conversations seemed quite muffled and unclear, and that he had an
annoying ringing in his ears. He then learned that his hearing problem
was permanent and could not be improved with surgery or medication.*

# 1. Applicability of this chapter

You are required to follow this chapter if you work in an area that has
been designated a hazardous noise area or source, such as the flight
line at Ellington Field or machines in a sheet metal shop.

# 2. What this chapter covers

This chapter covers the minimum requirements for JSC's hearing
conservation program (HCP). It discusses JSC's efforts to prevent
noise-induced hearing loss among employees who are exposed to hazardous
noise while working at this center. JSC managers, supervisors, and
employees share responsibilities for meeting these requirements.

# 3. Policy

These documents govern JSC's hearing conservation policies:

a.  NPR 1800.1 Chapter 4.9 describes the general requirements and
    provisions of NASA's HCP.

b.  29 CFR 1910.95, "Occupational Noise Exposure," and its appendices
    describe OSHA's hearing conservation standards.

c.  29 CFR 1904.10, "Occupational Injury and Illness Recordkeeping and
    Reporting Requirements," describes OSHA's requirements for recording
    and reporting noise-related hearing loss.

# 4. HCP elements

The success of the JSC HCP requires support from managers, medical
personnel, supervisors, and employees in conduct of:

a.  Buy Quiet and Quiet by Design program and noise control requirements
    and strategies.

b.  Noise exposure monitoring.

c.  Medical surveillance and audiometric testing.

d.  Selection, use, and inspection of hearing protectors.

e.  Training.

f.  Policy, documentation, and recordkeeping.

g.  Effective implementation of engineering, operational, and
    administrative controls.

h.  Appropriate corrective actions for employees who violate any HCP
    requirements.

# 5. What is "too noisy"

NASA's hearing conservation policy considers occupational noise to be
potentially hazardous to hearing if the exposure is greater than the
equivalent of 82 decibels on the A-weighted scale (dBA) over an 8-hour
time-weighted average (TWA~8hr~). This is the JSC "action level." Noise
exposures greater than the equivalent of 85 dBA TWA~8hr~ exceed JSC's
"criterion level." The following apply:

a.  You shall be enrolled in the JSC HCP whenever you are exposed to:

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1.  Noise levels that exceed the JSC action level of 82 dBA TWA~8hr~ for
    30 or more days per year.

2.  Noise levels that exceed the JSC action level of 85 dBA TWA~8hr~ for
    1 or more days per year.

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b.  This table shows exposures to the JSC action level and permissible
    level. As noise levels increase, it takes less time to get the same
    exposure.

  ------------------------- ---------------------- ----------------------
  ***Decibel\* limit***     NASA Action Level      NASA Permissible Level
                            (Duration in hours)    (Duration in hours)

  82                        8                      16

  85                        4                      8

  88                        2                      4

  91                        1                      2

  94                        0.5                    .1

  97                        0.25                   .5

  100                       0.13                   .25

  103                       0.06 or less           0.13
  ------------------------- ---------------------- ----------------------

> \*Measured in dBA, with sound level meter set at "slow response."

c.  For impact and impulse noise, "too noisy" is anything that exceeds
    140 dB peak sound pressure level.

d.  Under no circumstances are you to be exposed to noise exceeding 85
    dB continuous noise or 140 dB impulse or impact noise without
    personal hearing protection devices (HPDs).

# 6. How to determine whether your work area is too noisy

The easiest way to know if your work area is too noisy is to check for
hazardous-noise warning signs posted just outside the hazard areas or
for warning labels on power tools or machines. If you have to shout at
someone 3 feet away from you to make yourself understood, the levels in
that area may be exceeding 82 dBA. If you think your work area or
machinery may be noise-hazardous but no warning signs or labels are
present, call the Occupational Health Department at (281) 483-6726 for
noise monitoring support. The Occupational Health Department will
complete the monitoring and report back to you in writing with their
findings and recommendations. If your work area is too noisy, you will
be notified that you may be included in the hearing conservation medical
monitoring program (see paragraph 10 of this chapter).

# 7. Selection, use, and inspection of HPDs

You shall wear HPDs, such as earmuffs or ear plugs if you are exposed to
continuous noise that equals or exceeds 85 dBA, independent of duration
of exposure or impulse noise that equals or exceeds 140 dB peak. HPDs
will also be available for use by employees working in areas with
nuisance noise levels, lower than 82 dBA TWA~8hr~. The follow
requirements apply to HPDs:

a.  You shall never trade or share earplugs. They are for your exclusive
    use only.

b.  HPDs shall attenuate employee noise exposure to an TWA~8hr~ of 85
    dBA or less. For employees who have shown a standard threshold shift
    (or STS, as described in paragraph 10), HPDs shall attenuate
    exposure to an TWA~8hr~ of 82 dBA or less.

c.  To determine the necessary noise reduction rating (NRR) of the
    manufacturer for any kind of HPD in a noisy environment, you shall
    use the following formula:

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1.  Required NRR = \[(L~A~ - 85) × 2\] + 7, where L~A~ is the measured
    ambient sound level to which the employee is exposed.

2.  You shall reevaluate the adequacy of HPD attenuation whenever
    employee noise exposures increase.

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d.  You shall regularly inspect special HPDs if they are used in
    hazardous noise areas.

e.  You shall never use earmuffs or sound-suppression and
    noise-cancellation headsets that have been damaged, altered, or
    modified in any way that affects the attenuation characteristics.

f.  The Occupational Health Department can recommend the best types of
    hearing protection to wear in a noise-hazardous area.

g.  The Occupational Health Department may reevaluate noise-hazardous
    areas whenever the noise level increases to see whether current HPDs
    are still adequate.

h.  You shall wear double protection (both earmuffs and earplugs) when
    analysis shows that the protection provided by earplugs doesn't
    reduce noise exposures below 85 dBA (TWA).

# 8. Engineering, operational, and administrative controls

You shall follow these requirements to control noise:

a.  Consider noise engineering control measures in the early stages of
    the design or planning process of engineering projects, drawings,
    and operational plans, and before contract award or authority to
    proceed. These controls should aim to reduce noise levels below
    82 dBA.

b.  If you plan to change facilities, operations, or procedures, you
    shall notify the JSC Occupational Health Office of:

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1.  Changes in operations or equipment that increase noise levels.

2.  New, uncontrolled, or previously unidentified areas, operations, or
    equipment that may produce hazardous noise or may not meet the
    requirements of this chapter.

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c.  If engineering controls fail to reduce sound levels and hearing
    protective equipment is not sufficient to attenuate noise to less
    than 82 dBA, you shall use:

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1.  Administrative controls. These controls may include limiting the
    duration of time spent in, or control of access to, the
    noise-hazardous area.

2.  Operational controls, such as maximizing distances between the
    employee and the hazardous noise source, when practical.

# 9. "Buy Quiet and Quiet by Design" Program

The "Buy Quiet and Quiet by Design" Program aims to reduce employee
noise exposures through early consideration of the noise outputs of
systems, facilities, and equipment before their purchase and design. JSC
designers and engineers should consider noise emissions when purchasing
and designing equipment that is expected to generate noise emission
levels of concern for hearing conservation (80 dBA and higher). The JSC
"Buy Quiet and Quiet by Design" Program shall:

a.  Be integral to the site selection and design of new or modified
    facilities and equipment.

b.  Meet realistic and achievable baseline noise criteria and optimize
    noise emission criteria based on individual and specific operational
    and site conditions.

c.  Encompass design and development, or selection and purchase, of a
    broad variety of fixed and portable equipment purchased for use by
    JSC organizations, including equipment purchased by contractors, to
    minimize noise-exposure hazards to personnel.

d.  Encompass equipment expected to produce noise that is approaching
    hearing conservation levels of 80 dBA and higher under a variety of
    site and operational considerations.

e.  Identify noise emission and control requirements for equipment
    procurement specifications and design.

f.  Contain provisions for "Buy Quiet and Quiet by Design" program
    support, promotion, training, and management sponsorship.

g.  Be individualized to meet an organization's specific needs,
    configuration, and other relevant factors.

h.  Not apply to specialized research project items or flight hardware,
    which may be expected to produce large amounts of noise.

i.  Be included in all contracts and in the purchase of new equipment,
    as appropriate. Contracting Officers and Contracting Officer's
    Technical Representatives shall ensure that these provisions are
    included.

# 10. Medical surveillance and audiometric examinations (hearing tests)

You shall be included in the HCP medical surveillance program and
receive periodic audiometric examinations if you are exposed to noise
levels that exceed the NASA action level of 82 dBA TWA~8hr~ for at least
1 day. There are three types of exams:

a.  *Baseline exam*. Within 30 days of initial exposure to hazardous
    noise, noise-exposed employees should receive a baseline medical
    examination. Results of subsequent hearing tests will be compared to
    the results of the baseline hearing test. The baseline exam shall
    follow these requirements:

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1.  Include a hearing test (preceded by at least 14 hours without high
    noise exposures).

2.  Include a medical examination to determine any preexisting ear
    problems.

3.  Include a noise exposure history to document past noise exposures.

4.  Occupational health personnel will review the hearing test results
    and may recommend a referral to an audiologist or s physician for
    further evaluation.

5.  The employee and his or her supervisor shall receive a written
    notification of any hearing condition that may impair the employee's
    ability to safely hear commands or signals on job.

6.  If a contract is awarded to a new contractor and the same employee
    of the former employer occupies the same work role position, without
    an appreciable change in noise exposure, continue to use the
    original audiometric baseline.

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b.  *Annual exam*. Noise-exposed employees shall, at least every 12
    months, receive an audiometric exam that includes:

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1.  A hearing test (no special provisions for avoiding noise are
    needed).

2.  An update to their exposure and medical history.

3.  An evaluation for an STS. If a decline in hearing threshold of 10 dB
    (average) or more from baseline thresholds at 2000, 3000, and 4000
    Hz in either ear is found in the annual audiometric examination,
    additional testing is required.

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c.  *Final (termination) exam*. If you have participated in the HCP
    medical surveillance program, you shall receive a final audiometric
    exam before ending employment, transfer to duties not involving
    noise exposures, transfer to another installation, or retirement. If
    an annual audiogram has been completed within 6 months of the
    termination, transfer, or retirement date, those results may be
    used.

# 11. Hearing conservation training

If you are exposed to noise at or exceeding the NASA action levels (see
paragraph 5 of this chapter), you and your supervisor shall receive
annual training from the Occupational Health Department in the hazards
of noise exposure to include:

a.  Elements of JSC's HCP.

b.  The roles and responsibilities of noise-exposed employees.

c.  Effects of hazardous noise on and factors that may contribute to
    hearing loss.

d.  Hazardous noise sources in the employee's JSC work areas.

e.  Noise control practices, including use of hearing protection during
    home activities.

f.  The purpose, types, fitting, proper use, advantages and
    disadvantages, and maintenance of HPDs.

g.  An explanation of Occupational Health Department's audiometric
    testing purpose and procedures.

**12. HCP records**

The following recordkeeping requirements apply to JSC's HCP:

a.  Supervisors shall maintain a registry of personnel enrolled in their
    activity's hearing conservation program. Forward an updated listing
    of these personnel to JSC Occupational Health Department once per
    quarter.

b.  The Occupational Health Department shall maintain JSC's
    comprehensive registry of all noise-hazardous areas and personnel
    placed in the JSC Hearing Conservation Program. This includes a
    database of audiometric test records, audiometer calibration data,
    noise level surveys, noise-exposure assessments, and hearing
    conservation training records

c.  An employer shall log any STS (using age corrections for the hearing
    loss) as an OSHA-recordable event on the OSHA 300 log per 29 CFR
    1904.10 and NPR 1800.1 if both of the following are true:

-   The hearing loss now exceeds 25 dB (when averaging hearing
    thresholds at 2000, 3000, and 4000 Hz) in the same ear.

-   The hearing is determined to be work related.

# 13. Other potential noise exposures

In addition to noise exposures at work, your activities off the job may
also cause hearing loss. Some of these activities include:

a.  Motorized vehicles and equipment such as: motorcycles, boats, lawn
    mowers, and power tools (saws, drills, etc.).

b.  Recreational use of fire arms.

c.  Audio equipment such as: radios, televisions, and musical instrument
    amplifiers if the volume is set too high.

d.  Attendance at concerts and night clubs.