Attach_12_Personal_Protective_Policies_-_Hearing_Conservation.pdf

3. Personal Protection Procedures

G. HEARING CONSERVATION PROGRAM

Safety & Health Officer: _______________________________________ Date: _____________

Revised by J.D. 9/21/09

TABLE OF CONTENTS

1. Procedure

2. References

3. Definitions

a. Decibel

b. Action Level

c. Sound level meter and octave band analyzer

d. Audiogram

e. STS

4. Responsibilities

a. Supervisor

b. Employee

c. Safety Office

5. Guidelines

a. Monitoring

b. Audiometric Testing

c. Recordkeeping

d. Hearing Protectors

Revised by J.D. 9/21/09

Revised by J.D. 9/21/09 1

1. Procedure

All employees will be protected against the detrimental effects of excessive noise exposure. Feasible administrative or engineering controls shall be utilized when employees are subjected to sound levels exceeding those listed in Table 1. If such controls fail to reduce sound below the levels of Table 1, personal protective equipment shall be provided and used to reduce exposures to within permissible levels. If the variations in noise level involve maxima at intervals of 1 second or less, the noise is to be considered continuous. In all cases where the noise exposures exceed the values shown herein, a continuing, effective hearing conservation program shall be administered.

2. References

29 CFR 1910.95, Occupational Noise Exposure

Fundamentals of Industrial Hygiene, 3rd Edition, National Safety Council, 1988

3. Definitions

a. Decibel (dB) - A unit used to express sound power level (LW). Sound power is the total acoustic output of a sound source in watts (W). By definition, sound power level, in decibels, is:

LW = 10 log W / Wo

Where W is the sound power of the source and Wo is the reference power.

b. Action Level - An 8-hour time-weighted average of 85 decibels measured on the A-scale slow response, or equivalently, a dose of fifty percent.

c. Sound level meter and octave band analyzer - Instruments for measuring sound pressure levels in decibels referenced to 0.0002 microbars. Readings can also be made in specific octave bands, usually beginning at 75 Hz and continuing through 10,000 Hz.

d. Audiogram - the record of a given individual's hearing sensitivity. An audiogram shows hearing threshold level measured in decibels as a function of frequency measured in hertz.

e. STS - Standard Threshold Shift - is an average shift in either ear of 10dBA or more at 2000, 3000 and 4000-Hz frequencies.

4. Responsibilities

a. Supervisor

1. Maintains an awareness of the approximate noise levels in work places for which he/she is responsible.

2. Requests a survey from the Safety Office when a change in equipment or procedure may increase employee exposure to noise.

3. Ensures that all employees are aware of the requirements for hearing protection in any area that has been identified as having levels which exceed permissible exposure limits.

4. Ensures that appropriate protective devices are worn and that any other control measures are observed.

b. Employee

1. Complies with the recommendations of the Safety Office and supervisor for controlling noise exposure.

2. Makes proper use of the hearing protection devices provided by the

Safety Office.

3. Reports any suspected change in noise levels of equipment to the Safety

Office so that a survey can be made.

4. Participates in audiometric testing or other hearing conservation programs as required by Institute procedure.

c. Safety Office

1. Performs noise surveys in all areas of NIOSH as required.

2. Identifies those areas where hearing protection is required and establishes total daily permissible exposure times.

3. Places warning signs in areas where sound levels exceed those in Table

1.

4. Approves and issues all hearing protection devices used by NIOSH employees. Provides instruction on the proper use, care, and maintenance of these devices.

5. Recommends, after consultation with Facilities Engineering, Revised by J.D. 8/29/06 engineering methods for controlling noise levels when such measures are considered feasible.

6. Makes arrangements for audiometric tests as required by OSHA regulations and Institute procedure.

Table 1 - Permissible Noise Exposure

Duration Per Day (hours)

Sound Level Slow Response (dBA)

1-1/2

1/2

1/4 or less

Note: When the daily noise exposure is composed of two or more periods of noise exposure of different levels, their combined effect should be considered, rather than the individual effect of each.

If the sum of the following fractions: C1/T1 + C2/T2... Cn/Tn exceeds 100 percent, then the mixed exposure should be considered to exceed the limit value.

Cn indicates the total time of exposure at a specified noise level, and Tn indicates the total time of exposure permitted at that level.

Exposure to impulsive or impact noise should not exceed 140 dBA peak sound pressure level.

5. Guidelines

a. Monitoring - It is the responsibility of the Safety Office to monitor noise exposure levels in a manner that will accurately identify employees who are exposed at or above an 8-hour time-weighted average (TWA) of 85 dBA. The exposure measurement will include all noise within an 80 dBA to 130 dBA range.

The Safety Office will remonitor employee's exposures whenever a change in the production process, equipment or controls increase noise exposure enough to require new hearing protectors, or brings additional employees to or above the action level. Each employee will be informed of monitoring results when exposed at or above the action level.

b. Audiometric Testing - Audiometric testing monitors changes in employee hearing acuity over time. The audiometric testing program includes baseline audiograms, annual audiograms, training and follow-up procedures. Audiometric testing shall be made available to all employees who have 8-hour time weighted average exposure levels of 85 dBA or higher. All audiometric tests shall be conducted following procedures established by the Occupational Safety and Health Administration.

1. Baseline audiograms are the reference audiograms against which future audiograms are compared. These audiograms shall be completed within six months after an employee's first exposure at the action level, or within one year if van service monitoring is used. Hearing protectors shall also be used to maintain the required quiet period before baseline audiograms are taken.

2. Annual audiograms shall be taken for comparison against baseline audiograms to determine if an employee has lost a sufficient amount of hearing ability to trigger follow-up procedures (i.e., to determine if a standard threshold shift (STS) has occurred).

3. Training shall be provided at least annually for employees exposed to time-weighted averages of 85 dBA and above. It will focus on the effects of noise; the purpose, advantages, disadvantages, and attenuation of various types of hearing protectors; the selection, fitting and care of protection; and the purpose and procedures of audiometric testing.

c. Recordkeeping - Noise exposure measurement records shall be kept for two years and audiometric test results for the duration of a worker's employment.

They shall include the employee's name and job classification and his or her most recent noise exposure measurement, and date and the examiner's name, the date of acoustic or exhaustive calibration, measurements of the background sound pressure levels in audiometric test rooms, and the employee's most recent noise exposure measurement.

d. Hearing Protectors - Hearing protectors shall be made available to all employees exposed at or above the action level. These protectors shall be capable of attenuating noise levels to at least a time-weighted average of 90 dBA for all employees and 85 dBA for employees who have experienced a standard threshold shift (STS). The Safety Office offers a choice of protectors from a variety of suitable types.