Document owner and change code Document Owner Aaron Perronne Title HSSE Manager Mark X Change Code Description X N/A First Issue A Typographical/Grammatical correction; formatting change; text clarification-no action required B Change requiring minor adjustment to process and/or records; users to be informed-no retraining required C Major change to the process and/or records; retraining of involved personnel to be conducted Table of Contents Document Owner and Change Code...1 1. Objective..2 2. Engineering and Administrative Control..2 3. Monitoring..... 3 4. Hearing Protection 6 5. Training....8 6. Recordkeeping.8 Page 1 of 9
1 OBJECTIVE The purpose of this Program is to protect employees against the effects of occupational noise exposures. Occupational hearing loss is a hearing impairment of one or both ears, partial or complete, arising in or during the course of one s employment. This includes acoustical trauma and noise-induced hearing loss. Acoustical trauma is an injury to the sensorineural parts of the inner ear. This is usually caused by one or a few exposures to sudden intense noises resulting from blasts and explosions or from a direct trauma to the head. Noise-induced hearing loss describes the long-term permanent hearing loss that develops over months or years of exposure to hazardous noise levels. The program shall be administered whenever employee noise exposures equal or exceed an 8-hour time-weighted average sound level (TWA) of 85 decibels on the A scale (dba), slow response. The Program Administrator is the person having overall responsibility for the Program. The program will be reviewed and updated as necessary. Copies of the written program may be obtained at the main office. If after reading this program, you find that improvements can be made, please contact the Program Administrator. 2 ENGINEERING AND ADMINISTRATIVE CONTROLS Engineering and administrative controls will be utilized when noise levels exceed 90 dba for an 8-hour TWA. If the hazard still exists, the use of personal protective equipment shall be provided and used to reduce noise levels. Engineering controls are procedures that reduce noise levels either at the source or along the path to the worker. Mechanical Systems, Inc. will use engineering controls when feasible as the best way to reduce a noise is at its source. Examples of engineering controls include installing a quieter exhaust, placing a machine on a rubber mat to reduce vibrations, or stopping the vibration of parts on a machine. If the noise cannot be reduced at the source, the path to the listener will be the next area to evaluate. There are many ways to modify the noise in its path. The machinery or equipment can be separated from the worker by using a shield. The worker can be moved away from the equipment. Distance is a very useful tool in noise reduction. The source can be enclosed or acoustic material can be put on the walls or hung from the ceiling. Administrative controls most often refer to scheduling. This could be scheduling of how long an employee can work in a high noise area or scheduling how long noisy equipment can be operated each day or each week. Administrative controls also include rotating schedules and transferring employees out of high noise areas. Page 2 of 9
3 MONITORING Noise monitoring will be done with a sound level meter or a dosimeter. The sound level meter measures the intensity of a sound at that given moment, so to determine a TWA, several measurements would have to be taken at various times during the work shift to estimate the noise exposure. The dosimeter also measures sound intensity, but it also stores the sound level measurements over time, providing an average noise exposure for a given work shift. WHEN TO MONITOR Noise monitoring must be conducted when exposures equal or exceed 85 dba. The exposure measurements will include all noise within an 80-130 dba range. Employee complaints about the noise, indications that employees are losing their hearing, and noticeable noise from equipment and machinery are some indications that monitoring needs to be done. TYPES OF MEASUREMENTS Area Measurements Using a SLM set for A-Scale and slow response to record the regular occurring maximum and minimum noise levels at the center of the work area. This area monitoring is only for areas up to 1000 sq. ft. If the maximum sound level does not exceed 80 dba, it is assumed that all the employees are safe. If the levels at the center of the work area are between 80 and 92 dba, then more information is needed. Workstation Measurements Workstation measurements are done when the area measurements show noise levels between 80 and 92 dba from the center of the work area. The measurements should be made at each employee's workstation. If the noise level varies, record both the maximum and the minimum. If the level is constantly above 90 dba, then an unsatisfactory condition exists. If the level never exceeds 85 dba, the noise exposure is considered satisfactory. MONITORING INTERVALS Monitoring will be repeated every (3) years and within 60 days of there being change in production, process, equipment or controls that increase the noise exposures to the point where previously unaffected employees will be exposed or the hearing protection provided prior to the change is not inadequate. Page 3 of 9
INSTRUMENTATION CALIBRATION All noise measuring instruments shall be calibrated to ensure accurate readings. The recommendation is to calibrate prior to every noise monitoring campaign. Calibration shall be in compliance with OSHA 29 CFR 1910.95 (5) (i-iii). Employee Written Notification Employees whose work environment results in exposure to greater than 85 dba on an 8 hour Time Weighted Average (TWA) shall be notified in writing within 21 days of the required reading. Employees shall be notified of the level of exposure to which they, or their selected representative, was exposed. New employees shall be notified, upon hiring, of the level of exposure to which they, or the selected representative, are currently being exposed. Signs shall be posted at entrances to all of the well-defined work areas where employees may be exposed at or above a time-weighted average of 85 dba. Posting signs shall clearly indicate that the area is a high noise level area and that hearing protection may be required. Audiometric Testing Program Audiometric testing is an important part of the Program. The objectives to accomplish are as follows: Obtain a baseline audiogram that indicates the employees hearing ability when first tested. To provide a record of employees test results. To record significant hearing threshold shifts in exposed employees during their course of employment. To check the effectiveness of the noise control measures being used. Comply with government regulations. An Audiometric Testing Program will be established to test all employees whose exposures equal or exceed an eight (8) hour TWA of 85 dba. A professional (audiologist, otolaryngologist, or physician) will be responsible for the program. A trained technician or a professional may conduct the audiometric testing. The program will be provided at no cost to employees. An audiometer is an electronic device that converts electrical energy into sound energy in precisely variable amounts. It consists of an oscillator, which produces pure tones at predetermined frequencies, an attenuator, which controls the intensity of the sound or tone produced, a presenter switch, and earphones, which the person being tested wears to hear the tones. Page 4 of 9
Audiometric tests will be pure tone, air conduction, hearing threshold examinations with test frequencies including at least 500-, 1000-, 2000-, 3000-, 4000-, and 6000-Hz. Tests must be taken separately for each ear. BASELINE AUDIOGRAM Baseline Audiograms will be provided within six (6) months of an employee's first exposure at or above a TWA of 85 dba. Testing for the Baseline Audiogram will be preceded by at least 14 hours without exposure to workplace noise. Hearing protection may be used to meet the requirement. The use of mobile vans to do the testing increases this time to one (1) year after the first exposure, although the affected employee will have to use hearing protectors at six (6) months after the first exposure, until the audiogram is obtained. Baseline Audiograms taken before the effective date will be accepted. The recommendation is that a baseline audiogram be done when employee is hired. The baseline will be used to compare against future audiograms. ANNUAL AUDIOGRAM At least annually after the baseline audiogram, the employee will be tested to obtain a new audiogram to compare against the baseline. STANDARD THRESHOLD SHIFT A Standard Threshold Shift (STS) occurs when there is an average shift (or loss) in both ears of 10 db or more at the 2000-, 3000-, and 4000-Hz frequencies. AUDIOGRAM EVALUATION Audiogram evaluations are done routinely by comparing baseline audiograms to determine whether the audiogram is accurate or if an employee has lost hearing ability. A technician will do this comparison. If a hearing loss or Standard Threshold Shift is identified, the employee must be fitted with adequate hearing protectors, shown how to use them, and required to wear them. FOLLOW-UP PROCEDURES If a Standard Threshold Shift is detected, the use of hearing protection shall be re-evaluated and/or refitted and if necessary a medical evaluation may be required. Employees will be notified in writing within 21 days from the time that it is determined that they have a Standard Threshold Shift. If, in the opinion of the professional, the employee needs further tests, the employee will be notified of what they are to do next. If a future audiogram shows that the Standard Threshold Shift is not persistent, and Page 5 of 9
the employee is exposed to an average level of 90 dba, they may discontinue the use of the hearing protectors. AUDIOMETRIC TESTING REQUIREMENTS Audiometric tests must meet OSHA 29 CFR 1910.95 (h), (1), (2), (3), (4), (5)(ii) and (iii). 4 HEARING PROTECTION As part of the OSHA standard 1910.95, Mechanical Systems, Inc. will make available hearing protectors to all employees exposed to an 8-hour TWA of 85 dba or greater at no cost. Engineering and administrative controls should always be used prior to the use of hearing protectors. Personal Protective Equipment is always the last resort. To determine what type and how good of a hearing protector the affected employee will need, several factors must be known. Characteristics of the noise in the area that is of concern must be known. Not only is the noise level a concern, but also the frequency of the noise. The frequency is important because different hearing protectors are more efficient at different frequencies. Earmuffs are better at reducing noise at high frequencies, while earplugs are more efficient at the lower frequencies. To obtain the frequency of noises, an Octave-band Analyzer can be used. Another factor is what type of work is being done. If space is limited, large earmuffs may not be practical. If the employee is around hazardous materials, the hearing protector should not be affected by the hazard. When a person is working around electrical hazards, the hearing protector should not be non-conductive. Other personal protective equipment like hard hats and safety glasses must also be considered. The best method to gauge the adequacy of a hearing protector is by checking its Noise Reduction Rating (NRR). The NRR must be printed on the hearing protector package. The following are examples of applying the NRR rating to the job site: The Selection, Fitting and Care of Hearing Protectors Mechanical Systems, Inc. will decide which type of protector is most suitable for employees through evaluating hearing protection for the specific noise environments in which the protection will be used. A designated person trained in fitting hearing protectors will help employees determine the appropriate size. The protectors should be comfortable to wear and must reduce employee exposure at least to an eight (8)-hour TWA of 90 dba and 85 dba for employees with standard threshold shifts (STS). Page 6 of 9
SELECTION FACTORS: The effectiveness in reducing decibel levels The work area The person using the protectors Other Personal Protective Equipment being used (hats, glasses) Frequency of exposure Cost effectiveness Employee Comfort FITTING - The type of protectors selected will affect the need for fitting and to what degree. CARE - Care also varies with the type of protector. The inserts should be disposed when designated by manufacturer instructions. Earmuffs currently on the market have replaced ear seals and cushions. The outer covering of the seals become stiff due to perspiration and will need to be replaced periodically, depending on the conditions of exposure. The Purpose, Advantages and Disadvantages of Various Hearing Protectors ENCLOSURES The enclosure type - protective devices are incorporated into equipment that entirely covers the head. By wearing hearing protectors, then adding a helmet that encloses the head, an additional 10 db less reaches the ears. Advantage - Helmet reduces noise if used with hearing protection, and protects the head. Disadvantages - Cost and Bulk AURAL INSERTS Normally referred to as inserts or earplugs. Made from such materials as rubber, plastics, fine glass down, foam, and wax-impregnated cotton. The employee s ears should be examined prior to using earplugs. There are three types of aural inserts: Formable, custom-molded, and premolded aural inserts. Advantages - Inexpensive, many different configurations, comfortable, and little danger of damaging the inner ear, fairly good attenuation. Disadvantages - Service life is limited and occasional allergic reaction to material. MOLDED EAR CAPS These protectors form the seal on the outside of the ear. Page 7 of 9
Advantages - More comfortable than Aural inserts. Disadvantages - Expensive, fit problems due to the variations in outer ear, attenuation less effective than Aural Inserts due to fitting problems. EARMUFFS Consist of two-cup or dome shaped devices that fit over the entire external ear, and a seal against the side of the head, along with a headband to hold them in place. Advantages - Considerable better attenuation than the ear plugs. Disadvantages - Expensive, larger than other protectors. 5 TRAINING Employees exposed to TWAs of 85 dba and above will participate in training at least annually. Information provided in the training program shall be updated as necessary to reflect changes in equipment or procedures. The training will include the following: The effects of noise on hearing The contents of the noise standard and hearing conservation programs The purpose, advantages, disadvantages and attenuation characteristics of various types of hearing protectors The selection, fitting and care of hearing protectors The purpose and procedures of audiometric testing The specific machinery that produces high noise levels Training will be updated consistent to changes in personal protective equipment and work processes. 6 RECORDKEEPING Noise exposure records will be kept for two (2) years. Audiometric records will be maintained for the duration of the affected employee's employment. Test room background sound pressure and audiometer calibration records should be kept for 5 years. The Audiometric test records will include the employee's name and job classification, the date the test was performed, the examiner's name, the date of the last acoustic or exhaustive calibration of the audiometer, measurements of the background sound pressure levels in the audiometric test rooms, and the employee's most recent noise exposure measurement. In addition, accurate records shall be maintained showing the measurement of the background sound pressure levels in the test room and records of all acoustical and exhaustive calibrations of audiometers that are required. Page 8 of 9
Access to Information and Records Mechanical Systems, Inc. will make available copies of noise exposure procedures to all affected employees and will also post a copy in the workplace. Employees have the right to see training information, the applicable OSHA standard 29 CFR 1910.95 and 1926.52, audiometric test records, and noise exposure records. The Assistant Secretary and the Director will also have access to applicable records. Page 9 of 9