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(continued)
(4) The employer shall provide affected employees or their representatives with an opportunity to observe any measurements of employee noise exposure which are conducted pursuant to this section.
(5) The employer shall notify each employee exposed at or above the action level of the results of the monitoring.
(c) Audiometric Testing Program.
(1) The employer shall establish and maintain an audiometric testing program as provided in this section by making audiometric testing available to all employees whose exposures equal or exceed the action level.
(2) The program shall be provided at no cost to employees.
(3) 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, or who has satisfactorily demonstrated competence in administering audiometric examinations, obtaining valid audiograms, and properly using, maintaining and checking calibration and proper functioning of the audiometers being used. A technician who performs audiometric tests must be responsible to an audiologist, otolaryngologist or physician.
(4) All audiograms obtained pursuant to this section shall meet the requirements of Appendix B: Audiometric Measuring Instruments.
(5) The employer shall establish for each employee exposed at or above the action level a valid baseline audiogram against which subsequent audiograms can be compared.
(6) Testing to establish a baseline audiogram shall be preceded by at least 14 hours without exposure to workplace noise. This requirement may be met by wearing hearing protectors which will reduce the employee's exposure to a sound level of 80 dBA or below.
(7) The employer shall notify employees of the need to avoid high levels of non-occupational noise exposure during the 14-hour period immediately preceding the audiometric examination.
(8) Audiometric tests shall be made available to employees by June 1, 1983 or within 6 months of an employee's first exposure at or above the action level, except that where a mobile test van is used to conduct the audiometric test, the test shall be made available within one year of an employee's first exposure at or above the action level provided that all such employees are given an opportunity for testing.
Note: This requirement may be met by an audiogram available to the employer upon the effective date of this section provided the conditions under which the audiometric test was performed were the same as prescribed by this section.
(9) Where an employer chooses to have audiometric tests performed by a mobile test van in accordance with Section 5097(c)(8) and an employee's baseline audiogram has not been obtained within 6 months of the employee's first exposure at or above the action level, the employer shall make hearing protectors available to the employee in accordance with Section 5098 and require that the hearing protectors are worn by the employee until the baseline audiogram is obtained.
(10) At least annually after obtaining the baseline audiogram, the employer shall obtain a new audiogram for each employee exposed at or above the action level.
(d) Evaluation of Audiogram.
(1) Each employee's annual audiogram shall be compared to that employee's baseline audiogram to determine if the audiogram is valid and if a standard threshold shift, as defined in Section 5097(d)(8), has occurred. This comparison may be done by a technician.
(2) If the annual audiogram shows that an employee has suffered a standard threshold shift, the employer may obtain a retest within 30 days and consider the results of the retest as the annual audiogram.
(3) An audiologist, otolaryngologist or physician shall review problem audiograms and shall determine whether there is a need for further evaluation. The employer shall provide to the person performing this evaluation the following information:
(A) A copy of the requirements for hearing conservation as set forth in Sections 5097, 5098, 5099 and 5100.
(B) The baseline audiogram and most recent audiogram of the employee to be evaluated.
(C) Measurements of background sound pressure levels in the audiometric test room as required in Appendix C, Audiometric Test Rooms.
(D) Records of audiometric calibrations required by paragraph (f) of this section.
(4) If a comparison of the annual audiogram to the baseline audiogram indicates a standard threshold shift as defined by Section 5097(d)(8), the employee shall be informed of this fact, in writing, within 21 days of the determination.
(5) Unless a physician determines that the standard threshold shift is not work related or aggravated by occupational noise exposure, the employer shall ensure that the following steps are taken when a standard threshold shift occurs:
(A) An employee not using hearing protectors shall be fitted with hearing protectors, trained in their use and care, and required to use them; and
(B) An employee already using hearing protectors shall be refitted and retrained in the use of hearing protectors and provided with hearing protectors offering greater attenuation if necessary.
(C) Refer the employee for a clinical audiological evaluation or an otological examination, as appropriate, if additional testing is necessary or if the employer suspects that a medical pathology of the ear is caused or aggravated by the wearing of hearing protectors.
(D) Inform the employee of the need for an otological examination if a medical pathology of the ear which is unrelated to the use of hearing protectors is suspected.
(6) If subsequent audiometric testing of an employee whose exposure to noise is less than an 8-hour time-weighted average of 90 decibels indicates that a standard threshold shift is not persistent, the employer:
(A) Shall inform the employee of the new audiometric interpretation; and
(B) May discontinue the required use of hearing protectors for that employee.
(7) An annual audiogram may be substituted for the baseline audiogram when in the judgment of the audiologist, otolaryngologist or physician who is evaluating the audiogram:
(A) The standard threshold shift revealed by the audiogram is persistent; or
(B) The hearing threshold shown in the annual audiogram indicates significant improvement over the baseline audiogram.
(8) As used in this section, a standard threshold shift is a change in hearing threshold relative to the baseline audiogram of an average of 10 dB or more at 2000, 3000 and 4000 Hz in either ear.
(9) In determining whether a standard threshold shift has occurred, allowance may be made for the contribution of aging (presbycusis) to the change in hearing level by correcting the annual audiogram according to the procedure described in Appendix F: Determination and Application of Age Correction to Audiograms.
(e) Audiometric Test Requirements.
(1) Audiometric tests shall be pure tone, air conduction, hearing threshold examinations, with test frequencies including as a minimum 500, 1000, 2000, 3000, 4000 and 6000 Hz. Tests at each frequency shall be taken separately for each ear.
(2) Audiometric tests shall be conducted with audiometers (including microprocessor audiometers) that meet the specifications of, and are maintained and used in accordance with, ANSI S3.6-1969.
(3) Pulsed-tone and self-recording audiometers, if used, shall meet the requirements specified in Appendix B, Audiometric Measuring Instruments.
(4) Audiometric examinations shall be administered in a room meeting the requirements listed in Appendix C, Audiometric Test Rooms.
(f) Audiometer Calibration.
(1) The functional operation of the audiometer shall be checked before each day's use by testing a person with known, stable hearing thresholds, and by listening to the audiometer's output to make sure that the output is free from distorted or unwanted sounds. Deviations of 10 dB or greater shall require an acoustic calibration.
(2) Audiometer calibration shall be checked acoustically at least annually in accordance with Appendix D, Acoustic Calibration of Audiometers. Test frequencies below 500 Hz and above 6000 Hz may be omitted from this check. Deviations of 15 dB or greater necessitate an exhaustive calibration.
(3) An exhaustive calibration shall be performed at least every two years in accordance with Sections 4.1.2, 4.1.3, 4.1.4.3, 4.2, 4.4.1, 4.4.2, 4.4.3, and 4.5 of ANSI S3.6-1969. Test frequencies below 500 Hz and above 6000 Hz may be omitted from this calibration.
Note: Authority and reference cited: Section 142.3, Labor Code.
s 5098. Hearing Protectors.
(a) General.
(1) Employers shall make hearing protectors available to all employees exposed to an 8-hour time-weighted average of 85 decibels or greater at no cost to the employees. Hearing protectors shall be replaced as necessary.
(2) Employers shall ensure that hearing protectors are worn by all employees:
(A) Who are required by Section 5096(b) to wear personal protective equipment; or
(B) Who are exposed to an 8-hour time-weighted average of 85 decibels or greater, and who:
1. Are required by Section 5097(c)(9) to wear hearing protectors because baseline audiograms have not yet been established; or
2. Have experienced a standard threshold shift.
(3) Employees shall be given the opportunity to select their hearing protectors from a variety of suitable hearing protectors provided by the employer.
(4) The employer shall provide training in the use and care of all hearing protectors provided to employees.
(5) The employer shall ensure proper initial fitting and supervise the correct use of all hearing protectors.
(b) Hearing Protector Attenuation.
(1) The employer shall evaluate hearing protector attenuation for the specific noise environments in which the protector will be used. The employer shall use one of the methods described in Appendix E, Methods for Estimating the Adequacy of Hearing Protector Attenuation.
(2) Hearing protectors must attenuate employee exposure at least to an 8-hour time-weighted average of 90 decibels as required by Section 5096(b).
(3) For employees who have experienced a standard threshold shift, hearing protectors must attenuate employee exposures to an 8-hour time-weighted average of 85 decibels or below.
(4) The adequacy of hearing protector attenuation shall be reevaluated whenever employee noise exposures increase to the extent that the hearing protectors provided may no longer provide adequate attenuation. The employer shall provide more effective hearing protectors where necessary.
Note: Authority and reference cited: Section 142.3, Labor Code.
s 5099. Training Program.
(a) General.
(1) The employer shall institute a training program for all employees who are exposed to noise at or above an 8-hour time-weighted average of 85 dBA, and shall ensure employee participation in such program.
(2) The training program shall be repeated annually for each employee included in the hearing conservation program. Information provided in the training program shall be updated to be consistent with changes in protective equipment and work processes.
(3) The employer shall ensure that each employee is informed of the following:
(A) The effects of noise on hearing;
(B) The purpose of hearing protectors, the advantages, disadvantages, and attenuation of various types, and instructions on selection, fitting, use, and care; and
(C) The purpose of audiometric testing, and an explanation of the test procedures.
(b) Access to Information and Training Materials.
(1) The employer shall make available to affected employees or their representatives copies of Article 105 and shall also post a copy in the workplace.
(2) The employer shall provide to affected employees any informational materials pertaining to this standard that are supplied to the employer by U.S. Department of Labor, Occupational Safety and Health Administration.
(3) The employer shall provide, upon request, all materials related to the employer's training and education program pertaining to this standard to authorized representatives of the Chief of the Division and the Director, National Institute for Occupational Safety and Health.
Note: Authority and reference cited: Section 142.3, Labor Code.
s 5100. Recordkeeping.
(a) Exposure Measurements.
The employer shall maintain an accurate record of all employee exposure measurements required by Section 5097(b).
(b) Audiometric Tests.
(1) The employer shall retain all employee audiograms obtained pursuant to Section 5097(c) and (d).
(2) This record shall include:
(A) Name and job classification of the employee.
(B) Date of the audiogram.
(C) The examiner's name.
(D) Date of the last acoustic or exhaustive calibration of the audiometer.
(E) Employee's most recent noise exposure assessment.
(c) Audiometric Test Rooms.
The employer shall maintain accurate records of the measurements required by Appendix C, Audiometric Test Rooms, of the background sound pressure levels in audiometric test rooms.
(d) Record Retention. The employer shall retain records required in this section for at least the following periods:
(1) Noise exposure measurement records shall be retained for 2 years.
(2) Audiometric test records shall be retained for the duration of the affected employee's employment.
(e) Access to Records. All records required by this section shall be provided upon request to employees, former employees, representatives designated by the individual employee and any authorized representative of the Chief of the Division. The provisions of Sections 3204(a)-(g) and (h) apply to access to records required by this section.
(f) Transfer of Records. If the employer ceases to do business, the employer shall transfer to the successor employer all records required to be maintained by this section, and the successor employer shall retain them for the remainder of the period prescribed in Section 5100(d).
Note: Authority and reference cited: Section 142.3, Labor Code.
Appendix A
Noise Exposure Computation
I. Computation of Employee Noise Exposure
(a) Noise dose is computed using Table A-1 as follows: When the sound level, L, is constant over the entire work shift, the noise dose, D, in percent, is given by: D = 100 C/T where C is the total length of the work day, in hours, and T is the reference duration corresponding to the measured sound level, L, as given in Table A-1 or by the formula shown as a footnote to that table.
(b) When the workshift noise exposure is composed of two or more periods of noise at different levels, the total noise dose over the work day is given by: D = 100 (C sub1 /T sub1 + C sub2 /T sub2 + ... + C subn /T subn), where Cn indicates the total time of exposure at a specific noise level, and Tn indicates the reference duration for that level as given by Table A-1.
(c) The eight-hour time-weighted average sound level (TWA), in decibels, may be computed from the dose, in percent, by means of the formula: TWA = 16.61 log sub10 (D/100) + 90. For an eight-hour workshift with the noise level constant over the entire shift, the TWA is equal to the measured sound level.
(d) A table relating dose and TWA is given in Section II.
Table A-1
A-weighted .... Reference .. A-weighted .... Reference
sound level, .. Duration ... sound level, .. Duration
L (decibel) ... T (hour) ... L (decibel) ... T (hour)
80............ 32 ......... 106............ 0.87
81............ 27.9 ....... 107............ 0.76
82............ 24.3 ....... 108............ 0.66
83............ 21.1 ....... 109............ 0.57
84............ 18.4 ....... 110............ 0.5
85............ 16 ......... 111............ 0.44
86............ 13.9 ....... 112............ 0.38
87............ 12.1 ....... 113............ 0.33
88............ 10.6 ....... 114............ 0.29
89............ 9.2 ........ 115............ 0.25
90............ 8 .......... 116............ 0.22
91............ 7.0 ........ 117............ 0.19
92............ 6.1 ........ 118............ 0.16
93............ 5.3 ........ 119............ 0.14
94............ 4.6 ........ 120............ 0.125
95............ 4 .......... 121............ 0.11
96............ 3.5 ........ 122............ 0.095
97............ 3.0 ........ 123............ 0.082
98............ 2.6 ........ 124............ 0.072
99............ 2.3 ........ 125............ 0.063
100............ 2 .......... 126............ 0.054
101............ 1.7 ........ 127............ 0.047
102............ 1.5 ........ 128............ 0.041
103............ 1.3 ........ 129............ 0.036
104............ 1.1 ........ 130............ 0.031
105............ 1
In the above table, the reference duration, T, is computed by
T =8 / 2 (L-90)/
where L is the measured A-weighted sound level.
II. Conversion Between "Dose" and "8-Hour Time-Weighted Average" Sound Level.
Noise exposure is usually measured with an audiodosimeter which gives a readout in terms of "dose." Dosimeter readings can be converted to an 8-hour time-weighted average sound level (TWA).
In order to convert the reading of a dosimeter into TWA, use Table A-2. This table applies to dosimeters that are set to calculate dose or percent exposure according to the relationships in Table A-1. So, for example, a dose of 91 percent over an eight hour day results in a TWA of 89.3 dB, and a dose of 50 percent corresponds to a TWA of 85 dB.
If the dose as read on the dosimeter is less than or greater than the values found in Table A-2, the TWA may be calculated by using the formula:
TWA = 16.61 log sup10 (D/100) + 90 where TWA = 8-hour time-weighted average sound level and D = accumulated dose in percent exposure.
Table A-2
Conversion from "Percent Noise Exposure" or "Dose" to "8-Hour
Time-Weighted Average Sound Level" (TWA)
Dose or ... TWA .... Dose or ... TWA .... Dose or TWA
Percent ............ Percent ............ Percent
Noise .............. Noise .............. Noise
Exposure ........... Exposure ........... Exposure
10........ 73.4 ... 116........ 91.1 ... 510..... 101.8
15........ 76.3 ... 117........ 91.1 ... 520..... 101.9
20........ 78.4 ... 118........ 91.2 ... 530..... 102.0
25........ 80.0 ... 119........ 91.3 ... 540..... 102.2
30........ 81.3 ... 120........ 91.3 ... 550..... 102.3
35........ 82.4 ... 125........ 91.6 ... 560..... 102.4
40........ 83.4 ... 130........ 91.9 ... 570..... 102.6
45........ 84.2 ... 135........ 92.2 ... 580..... 102.7
50........ 85.0 ... 140........ 92.4 ... 590..... 102.8
55........ 85.7 ... 145........ 92.7 ... 600..... 102.9
60........ 86.3 ... 150........ 92.9 ... 610..... 103.0
65........ 86.9 ... 155........ 93.2 ... 620..... 103.2
70........ 87.4 ... 160........ 93.4 ... 630..... 103.3
75........ 87.9 ... 165........ 93.6 ... 640..... 103.4
80........ 88.4 ... 170........ 93.8 ... 650..... 103.5
81........ 88.5 ... 175........ 94.0 ... 660..... 103.6
82........ 88.6 ... 180........ 94.2 ... 670..... 103.7
83........ 88.7 ... 185........ 94.4 ... 680..... 103.8
84........ 88.7 ... 190........ 94.6 ... 690..... 103.9
85........ 88.8 ... 195........ 94.8 ... 700..... 104.0
86........ 88.9 ... 200........ 95.0 ... 710..... 104.1
87........ 89.9 ... 210........ 95.4 ... 720..... 104.2
88........ 89.1 ... 220........ 95.7 ... 730..... 104.3
89........ 89.2 ... 230........ 96.0 ... 740..... 104.4
90........ 89.2 ... 240........ 96.3 ... 750..... 104.5
91........ 89.3 ... 250........ 96.6 ... 760..... 104.6
92........ 89.4 ... 260........ 96.9 ... 770..... 104.7
93........ 89.5 ... 270........ 97.2 ... 780..... 104.8
94........ 89.6 ... 280........ 97.4 ... 790..... 104.9
95........ 89.6 ... 290........ 97.7 ... 800..... 105.0
96........ 89.7 ... 300........ 97.9 ... 810..... 105.1
97........ 89.8 ... 310........ 98.2 ... 820..... 105.2
98........ 89.9 ... 320........ 98.4 ... 830..... 105.3
99........ 89.9 ... 330........ 98.6 ... 840..... 105.4
100........ 90.0 ... 340........ 98.8 ... 850..... 105.4
101........ 90.1 ... 350........ 99.0 ... 860..... 105.5
102........ 90.1 ... 360........ 99.2 ... 870..... 105.6
103........ 90.2 ... 370........ 99.4 ... 880..... 105.7
104........ 90.3 ... 380........ 99.6 ... 890..... 105.8
105........ 90.4 ... 390........ 99.8 ... 900..... 105.8
106........ 90.4 ... 400........ 100.0 .. 910..... 105.9
107........ 90.5 ... 410........ 100.2 .. 920..... 106.0
108........ 90.6 ... 420........ 100.4 .. 930..... 106.1
109........ 90.6 ... 430........ 100.5 .. 940..... 106.2
110........ 90.7 ... 440........ 100.7 .. 950..... 106.2
111........ 90.8 ... 450........ 100.8 .. 960..... 106.3
112........ 90.8 ... 460........ 101.0 .. 970..... 106.4
113........ 90.9 ... 470........ 101.2 .. 980..... 106.5
114........ 90.9 ... 480........ 101.3 .. 990..... 106.5
115........ 91.1 ... 490........ 101.5 .. 999..... 106.6
500........ 101.6 .. 500........ 101.6
Note: Authority and reference cited: Section 142.3, Labor Code.
Appendix B
Audiometric Measuring Instruments
I. In the event that pulsed-tone audiometers are used, they shall have tone on-time of at least 200 milliseconds.
II. Self-recording audiometers shall comply with the following requirements:
(a) The chart upon which the audiogram is traced shall have lines at positions corresponding to all multiples of 10 dB hearing level within the intensity range spanned by the audiometer. The lines shall be equally spaced and shall be separated by at least 1/4 inch. Additional increments are optional. The audiogram pen tracings shall not exceed 2 dB in width.
(b) It shall be possible to set the stylus manually at the 10-dB increment lines for calibration purposes.
(c) The slewing rate for the audiometer attenuator shall not be more than 6 dB/sec except that an initial slewing rate greater than 6 dB/sec is permitted at the beginning of each new test frequency, but only until the second subject response.
(d) The audiometer shall remain at each required test frequency for 30 seconds (_____+ 3 seconds). The audiogram shall be clearly marked at each change of frequency and the actual frequency change of the audiometer shall not deviate from the frequency boundaries marked on the audiogram by more than 3 seconds.
(e) It must be possible at each test frequency to place a horizontal line segment parallel to the time axis on the audiogram, such that the audiometric tracing crosses the line segment at least six times at that test frequency. At each test frequency, the threshold shall be the average of the midpoints of the tracing excursions.
Appendix C
Audiometric Test Rooms
Rooms used for audiometric testing shall not have background sound pressure levels exceeding those in Table C-1 when measured by equipment conforming at least to the Type 2 requirements of ANSI S1.4-1971 (R1976), and to the Class II requirements of ANSI S1.11-1971 (R1976).
Table C-1
Maximum Allowable Octave-Band Sound Pressure Levels for
Audiometric Test Rooms
Octave-band center
frequency (Hz)................. 500 .. 1000 .. 2000 .. 4000 8000
Sound pressure level (dB)....... 40 ... 40 .... 47 .... 57 62
Note: Authority and reference cited: Section 142.3, Labor Code.
Appendix D
Acoustic Calibration of Audiometers
I. Audiometer calibration shall be checked acoustically, at least annually, according to the procedures described in this Appendix. The equipment necessary to perform these measurements is a sound level meter, octave-band filter set, and a National Bureau of Standards 9A coupler. In making these measurements, the accuracy of the calibrating equipment shall be sufficient to determine that the audiometer is within the tolerances permitted by ANSI S3.6-1969.
(a) Sound Pressure Output Check.
(1) Place the earphone coupler over the microphone of the sound level meter and place the earphone on the coupler.
(2) Set the audiometer's hearing threshold level (HTL) dial to 70 dB.
(3) Measure the sound pressure level of the tones at each test frequency from 500 Hz through 6000 Hz for each earphone.
(4) At each frequency the readout on the sound level meter should correspond to the levels in Table D-1 or Table D-2, as appropriate, for the type of earphone, in the column entitled "sound level meter reading."
(b) Linearity Check.
(1) With the earphone in place, set the frequency to 1000 Hz and the HTL dial on the audiometer to 70 dB.
(2) Measure the sound levels in the coupler at each 10dB decrement from 70 dB to 10 dB, noting the sound level meter reading at each setting.
(3) For each 10-dB decrement on the audiometer, the sound level meter should indicate a corresponding 10 dB decrease.
(4) This measurement may be made electrically with a voltmeter connected to the earphone terminals.
(c) Tolerances.
When any of the measured sound levels deviate from the levels in Table D-1 or Table D-2 by 3 dB at any test frequency between 500 and 3000 Hz, 4 dB at 4000 Hz, or 5 dB at 6000 Hz, an exhaustive calibration is advised. An exhaustive calibration is required if the deviations are 15 dB or greater at any test frequency.
Table D-2
Reference Threshold Levels for Telephonics TDH-39 Earphones
Reference Threshold .. Sound Level
Level for TDH-39 ..... Meter Reading,
Frequency, .. Hz Earphones, dB ..... dB
500.......... 11.5 ................. 81.5
1000......... 7 .................... 77
2000......... 9 .................... 79
3000......... 10 ................... 80
4000......... 9.5 .................. 79.5
6000......... 15.5 ................. 85.5
Table D-2
Reference Threshold Levels for Telephonics-TDH-49 Earphones
Reference Threshold .. Sound Level
Level for TDH-49 ..... Meter Reading,
Frequency, Hz .. Earphones, dB ........ dB
500............. 13.5 ................. 83.5
1000............ 7.5 .................. 77.5
2000............ 11 ................... 81.0
3000............ 9.5 .................. 79.5
4000............ 10.5 ................. 80.5
6000............ 13.5 ................. 83.5
Note: Authority and reference cited: Section 142.3, Labor Code.
Appendix E
Methods for Estimating the Adequacy of Hearing Protector Attenuation
I. For employees who have experienced a standard threshold shift, hearing protector attenuation must be sufficient to reduce employee exposure to a TWA of 85 dB. Employers must select one of the following methods by which to estimate the adequacy of hearing protection attenuation.
II. The most convenient method is the Noise Reduction Rating (NRR) developed by the Environmental Protection Agency (EPA). According to EPA regulation, the NRR must be shown on the hearing protector package. The NRR is then related to an individual worker's noise environment in order to assess the adequacy of the attenuation of a given hearing protector. This Appendix describes four methods of using the NRR to determine whether a particular hearing protector provides adequate protection within a given exposure environment. Selection among the four procedures is dependent upon the employer's noise measuring instruments.
III. Instead of using the NRR, employers may evaluate the adequacy of hearing protector attenuation by using one of the three methods developed by the National Institute for Occupational Safety and Health (NIOSH), which are described in the "List of Personal Hearing Protectors and Attenuation Data," HEW Publication No. 76-120, 1975, pages 21-37. These methods are known as NIOSH methods #1, #2 and #3. The NRR described below is a simplification of NIOSH method #2. The most complex method is NIOSH method #1, which is probably the most accurate method since it uses the largest amount of spectral information from the individual employee's noise environment. As in the case of the NRR method described below, if one of the NIOSH methods is used, the selected method must be applied to an individual's noise environment to assess the adequacy of the attenuation. Employers should be careful to take a sufficient number of measurements in order to achieve a representative sample for each time segment.
Note: The employer must remember that calculated attenuation values reflect realistic values only to the extent that the protectors are properly fitted and worn.
IV. When using the NRR to assess hearing protector adequacy, one of the following methods must be used:
(a) When using a dosimeter that is capable of C-weighted measurements:
(1) Obtain the employee's C-weighted dose for the entire workshift, and convert to TWA (see Appendix A).
(2) Subtract the NRR from the C-weighted TWA to obtain the estimated A-weighted TWA under the ear protector.
(b) When using a dosimeter that is not capable of C-weighted measurements, the following method may be used:
(1) Convert the A-weighted dose to TWA (see Appendix A).
(2) Subtract 7 dB from the NRR.
(3) Subtract the remainder from the A-weighted TWA to obtain the estimated A-weighted TWA under the ear protector.
(c) When using a sound level meter set to the A-weighting network:
(1) Obtain the employee's A-weighted TWA.
(2) Subtract 7 dB from the NRR, and subtract the remainder from the A-weighted TWA to obtain the estimated A-weighted TWA under the ear protector.
(d) When using a sound level meter set on the C-weighting network:
(1) Obtain a representative sample of the C-weighted sound levels in the employee's environment.
(2) Subtract the NRR from the C-weighted average sound level to obtain the estimated A-weighted TWA under the ear protector.
Note: Authority and reference cited: Section 142.3, Labor Code.
Appendix F
Determination and Application of Age Corrections to Audiograms
As permitted by Section 5097(d)(9), increases in an employee's hearing thresholds, as evidenced by an audiogram taken subsequent to a baseline audiogram, may be adjusted (lowered) for presbycusis (hearing loss due to aging). The applicable correction values at various ages and sound frequencies are included in Table F. If the employer chooses to adjust an employee's audiogram pursuant to Section 5097(d)(9), the employer shall follow the procedure described below.
(a) Obtain from Table F the age correction values at each audiometric test frequency of interest (the hearing losses at 2000, 3000, and 4000Hz are relevant to the determination of whether a standard threshold shift, as defined by Section 5097(d)(8), may exist) for the employee by:
(1) Finding the age at which the most recent audiogram was taken and recording the corresponding age correction values; and
(2) Finding the age at which the baseline audiogram was taken and recording the corresponding age correction values.
(b) Subtract the values found in (a)(2) from those found in (a)(1). (The remainders from these subtractions represent the values (in decibels) which may be attributed to aging and are the values by which the most recent audiogram may be adjusted at the respective audiometric test frequencies.)
(c) Subtract the values found in (b) from the hearing threshold values of the most recent audiogram.
When the adjustment of an audiogram for hearing loss due to aging is performed for the purpose of determining whether a standard threshold shift has occurred, the above-described calculations may be restricted to the 2000, 3000, and 4000 Hz frequencies. If the average of the hearing threshold values at 2000, 3000, and 4000 Hz found in step (c), above, is equal to or greater than 10, then the employee has exhibited a standard threshold shift, and the employer must comply with various provisions of Section 5097(d) as well as certain other requirements such as Sections 5098(a)(2)(B)2 and (b)(3).
Table F Age Correction Values in Decibels for Males (M)
and Females (F)
Audiometric Test Frequencies (Hz)
Age ................... 1000 ..... 2000 3000 4000 6000
M ... F ... M ... F M F M F M F
20 or Younger....... 5 .. 7 ... 3 ... 4 4 3 5 3 8 6
21.................. 5 ... 7 ... 3 ... 4 4 4 5 3 8 6
22.................. 5 ... 7 ... 3 ... 4 4 4 5 4 8 6
23.................. 5 ... 7 ... 3 ... 5 4 4 6 4 9 7
24.................. 5 ... 7 ... 3 ... 5 5 4 6 4 9 7
25.................. 5 ... 8 ... 3 ... 5 5 4 7 4 10 7
26.................. 5 ... 8 ... 4 ... 5 5 5 7 4 10 8
27.................. 5 ... 8 ... 4 ... 5 6 5 7 5 11 8
28.................. 6 ... 8 ... 4 ... 5 6 5 8 5 11 8
29.................. 6 ... 8 ... 4 ... 5 6 5 8 5 12 9
30.................. 6 ... 8 ... 4 ... 6 6 5 9 5 12 9
31.................. 6 ... 8 ... 4 ... 6 7 6 9 5 13 9
32.................. 6 ... 9 ... 5 ... 6 7 6 10 6 14 10
33.................. 6 ... 9 ... 5 ... 6 7 6 10 6 14 10
34.................. 6 ... 9 ... 5 ... 6 8 6 11 6 15 10
35.................. 7 ... 9 ... 5 ... 6 8 7 11 7 15 11
36.................. 7 ... 9 ... 5 ... 7 9 7 12 7 16 11
37.................. 7 ... 9 ... 6 ... 7 9 7 12 7 17 12
38.................. 7 ... 10 .. 6 ... 7 9 7 13 7 17 12
39.................. 7 ... 10 .. 6 ... 7 10 8 14 8 18 12
40.................. 7 ... 10 .. 6 ... 7 10 8 14 8 19 13
41.................. 7 ... 10 .. 6 ... 8 10 8 14 8 20 13
42.................. 8 ... 10 .. 7 ... 8 11 9 16 9 20 13
43.................. 8 ... 11 .. 7 ... 8 12 9 16 9 21 14
44.................. 8 ... 11 .. 7 ... 8 12 9 17 9 22 14
45.................. 8 ... 11 .. 7 ... 8 13 10 18 10 23 15
46.................. 8 ... 11 .. 8 ... 9 13 10 19 10 24 15
47.................. 8 ... 11 .. 8 ... 9 14 10 19 11 24 16
48.................. 9 ... 12 .. 8 ... 9 14 11 20 11 25 16
49.................. 9 ... 12 .. 9 ... 9 15 11 21 11 26 16
50.................. 9 ... 12 .. 9 ... 10 16 11 22 12 27 17
51.................. 9 ... 12 .. 9 ... 10 16 12 23 12 28 17
52.................. 9 ... 12 .. 10 .. 10 17 12 24 13 29 18
53.................. 9 ... 13 .. 10 .. 10 18 13 25 13 30 18
54.................. 10 .. 13 .. 10 .. 11 18 13 26 14 31 19
55.................. 10 .. 13 .. 11 .. 11 19 14 27 14 32 19
56.................. 10 .. 13 .. 11 .. 11 20 14 28 15 34 20
57.................. 10 .. 13 .. 11 .. 11 21 15 29 15 35 20
58.................. 10 .. 14 .. 12 .. 12 22 15 31 16 36 21
59.................. 11 .. 14 .. 12 .. 12 22 16 32 16 37 21
60 or Older......... 11 .. 14 .. 13 .. 12 23 16 33 17 38 22
Note: Authority and reference cited: Section 142.3, Labor Code.
s 5110. Repetitive Motion Injuries.
(a) Scope and application. This section shall apply to a job, process, or operation where a repetitive motion injury (RMI) has occurred to more than one employee under the following conditions:
(1) Work related causation. The repetitive motion injuries (RMIs) were predominantly caused (i.e. 50% or more) by a repetitive job, process, or operation;
(2) Relationship between RMIs at the workplace. The employees incurring the RMIs were performing a job, process, or operation of identical work activity. Identical work activity means that the employees were performing the same repetitive motion task, such as but not limited to word processing, assembly, or loading;
(3) Medical requirements. The RMIs were musculoskeletal injuries that a licensed physician objectively identified and diagnosed; and
(4) Time requirements. The RMIs were reported by the employees to the employer in the last 12 months but not before July 3, 1997.
(b) Program designated to minimize RMIs. Every employer subject to this section shall establish and implement a program designed to minimize RMIs. The program shall include a worksite evaluation, control of exposures which have caused RMIs and training of employees.
(1) Worksite evaluation. Each job, process, or operation of identical work activity covered by this section or a representative number of such jobs, processes, or operations of identical work activities shall be evaluated for exposures which have caused RMIs.
(2) Control of exposures which have caused RMIs. Any exposures that caused RMIs shall, in a timely manner, be corrected or if not capable of being corrected have the exposures minimized to the extent feasible. The employer shall consider engineering controls, such as work station redesign, adjustable fixtures or tool redesign, and administrative controls, such as job rotation, work pacing or work breaks.
(3) Training. Employees shall be provided training that includes an explanation of:
(A) The employer's program;
(B) The exposures which have been associated with RMIs;
(C) The symptoms and consequences of injuries caused by repetitive motion;
(D) The importance of reporting symptoms and injuries to the employer; and
(E) Methods used by the employer to minimize RMIs.
(c) Satisfaction of an employer's obligation. Measures implemented by an employer under subsection (b)(1), (b)(2), or (b)(3) shall satisfy the employer's obligation under that respective subsection, unless it is shown that a measure known to but not taken by the employer is substantially certain to cause a greater reduction in such injuries and that this alternative measure would not impose additional unreasonable costs.
Note: Authority cited: Sections 142.3 and 6357, Labor Code. Reference: Sections 142.3 and 6357, Labor Code; and Pulaski v. Occupational Safety & Health Stds. Bd. (1999) 75 Cal.App.4th 1315 [90 Cal. Rptr. 2d 54].
s 5139. Purpose.
Article 107 sets up minimum standards for the prevention of harmful exposure of employees to dusts, fumes, mists, vapors, and gases. (Title 24, T8-5139)
s 5140. Definitions.
As used in Article 107:
Abrasive-blasting respirator. A continuous flow supplied-air respirator constructed so that it will cover the wearer's head, neck, and shoulders to protect him from airborne dust and rebounding abrasive.
Abrasive wheels. An abrasive wheel is a power-driven wheel consisting of abrasive particles held together by artificial or natural, mineral or organic bonds. Metal, wooden, cloth or paper wheels or discs having a layer or layers of abrasive on the surface are not included. Natural sandstones (quarried) are not included.
Administrative control. Any procedure which limits exposure by adjustment of the work schedule.
Blast-cleaning enclosures. These include rotary blast cleaning tables, blast cleaning barrels and drums, abrasive blasting cabinets, blast cleaning rooms, abrasive separators, and similar enclosures. In blast cleaning rooms the operator works inside to operate the blasting nozzle; at blasting cabinets the operator directs the nozzle through openings in the cabinets. In other types of enclosures operation is automatic.
Branch duct. The part of an exhaust system piping or ductwork that is connected directly to the hood or enclosure.
Duct. Any pipe, flume, or channel, forming a part of a ventilating system, used to convey air, dusts, fumes, mists, vapors or gases.
Dust. Particles of solid matter, other than fumes, in such a state of comminution that they may be inhaled.
Engineering controls. Methods of controlling occupational exposure to injurious materials or conditions by means of general or local exhaust ventilation, substitution by a less hazardous material, by process modification, or by isolation or enclosure of health hazard-producing operations or machinery.
Exhaust purifier device. It is given a broad interpretation as any reliable and identifiable appliance added to an internal combustion engine to reduce toxic exhaust products. Special fuel additives may be certified as part of a device provided that other toxic components of exhaust are not increased significantly.
Exhaust system. A complete suction installation including all hoods, ducts, fans, jets, separators, and receptacles when required, and any other part necessary for the proper installation and operation thereof.
Fan. A rotary machine which creates the movement of air in the exhaust or ventilation system.
Fumes. Solid particles generated by condensation from the gaseous state, generally after volatilization from molten metals, etc., and often accompanied by a chemical reaction such as oxidation.
Gas. An aeriform fluid.
General ventilation. That type of ventilation which provides for general movement of air throughout rooms or buildings by either a gravity system or a mechanical system.
Gravity system of ventilation. One which depends wholly upon relative air density.
Harmful exposure. An exposure to dusts, fumes, mists, vapors, or gases:
(a) In excess of any permissible limit prescribed by Section 5155; or
(b) Of such a nature by inhalation as to result in, or have a probability to result in, injury, illness, disease, impairment, or loss of function.
Hazard. A source of risk, danger, or peril capable of causing injury. As used in Article 107, this meaning refers to dusts, fumes, mists, vapors, gases or chemicals capable of producing adverse health effects.
Hood. A shaped inlet designed to capture contaminated air and conduct it into the exhaust duct system.
Isolated operation. One which is carried on in a location where, or at such time that, no employee except those actually engaged in the operation involved is exposed to the hazards resulting therefrom.
Local exhaust ventilation. A mechanical ventilation system in which a hood is located at or near the point of release of dusts, fumes, mists, vapors or gases.
Main duct. A pipe or duct into which one or more branch ducts enter and which connects such branch ducts to the remainder of the exhaust system.
Mechanical ventilation system. One which depends upon power-driven equipment for its operation.
Mists. Suspended liquid droplets generated by condensation from gaseous to liquid state or by breaking up a liquid into a dispersed state, as by splashing, foaming, or atomizing.
Pitot traverse. The measurement of the air velocity in a duct using a pitot tube at several points in order to obtain an accurate average value of air velocity in the duct.
Separator/collector. The part of the exhaust system in which entrained material is separated from the air which conveys it.
Spray booth or Room. A power-ventilated structure provided to enclose or accommodate a spraying operation, to confine and limit the escape of spray, vapor and residue, and to safely conduct or direct them to an exhaust system.
Toxic material. A material in concentration or amount which exceeds the applicable limit established by a standard, such as Sections 5155, 5208, and 5209 or, in the absence of an applicable standard, which has the capacity to produce personal injury or illness to persons through ingestion, inhalation, or absorption through any body surface.
Vapor. The gaseous form of a substance normally liquid or solid.(Title 24, T8- 5140)
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5141. Control of Harmful Exposure to Employees.
(a) Engineering Controls. Harmful exposures shall be prevented by engineering controls whenever feasible.
(b) Administrative Controls. Whenever engineering controls are not feasible or do not achieve full compliance, administrative controls shall be implemented if practicable.
(c) Control by Respiratory Protective Equipment. Respiratory protective equipment, in accordance with Section 5144, shall be used to prevent harmful exposures as follows:
(1) During the time period necessary to install or implement feasible engineering controls;
(2) Where feasible engineering controls and administrative controls fail to achieve full compliance; and
(3) In emergencies.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5142. Mechanically Driven Heating, Ventilating and Air Conditioning (HVAC) Systems to Provide Minimum Building Ventilation.
(a) Operation:
(1) The HVAC system shall be maintained and operated to provide at least the quantity of outdoor air required by the State Building Standards Code, Title 24, Part 2, California Administrative Code, in effect at the time the building permit was issued.
(2) The HVAC system shall be operated continuously during working hours except:
(A) during scheduled maintenance and emergency repairs;
(B) during periods not exceeding a total of 90 hours per calendar year when a serving electric utility by contractual arrangement requests its customers to decrease electrical power demand; or
(C) during periods for which the employer can demonstrate that the quantity of outdoor air supplied by nonmechanical means meets the outdoor air supply rate required by (a)(1) of this Section. The employer must have available a record of calculations and/or measurements substantiating that the required outdoor air supply rate is satisfied by infiltration and/or by a nonmechanically driven outdoor air supply system.
(b) Inspection and Maintenance:
(1) The HVAC system shall be inspected at least annually, and problems found during these inspections shall be corrected within areasonable time.
(2) Inspections and maintenance of the HVAC system shall be documented in writing. The employer shall record the name of the individual(s) inspecting and/or maintaining the system, the date of the inspection and/or maintenance, and the specific findings and actions taken. The employer shall ensure that such records are retained for at least five years.
(3) The employer shall make all records required by this section available for examination and copying, within 48 hours of a request, to any authorized representative of the Division (as defined in Section 3207), to any employee of the employer affected by this section, and to any designated representative of said employee of the employer affected by this section.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5143. General Requirements of Mechanical Ventilation Systems.
(a) Design and Operation. The construction, installation, inspection, testing, and maintenance of exhaust systems shall conform to all requirements of Article 107. Additional guidance may be obtained from the American National Standard Fundamentals Governing the Design and Operation of Local Exhaust Systems, ANSI Z9.2-1971 and the Standard for the Installation of Blower and Exhaust Systems, NFPA No. 91-1973. Note:Ventilation requirements for control of flammable vapors are prescribed in Sections 5153(d) and 5416.
(1) The exhaust system shall be so designed, constructed, maintained and operated as to prevent harmful exposure by maintaining a volume and velocity of exhaust air sufficient to gather dusts, fumes, mists, vapors or gases from said equipment or process and to convey them to suitable points of safe disposal, thereby preventing their dispersion in harmful quantities into the atmosphere of work rooms or other places where persons are employed.
(2) Exhaust ducts, inlet ducts, and fan plenums shall be so designed, constructed, and supported as to prevent collapse of the ducts and/or failure of the supporting system.
(3) Exhaust ducts which convey dusts, fumes, and mists shall be provided with inspection or clean-out doors at intervals not to exceed 12 feet of horizontal running length for ducts up to 12 inches in diameter, but the distance may be greater for larger ducts. A clean-out door or doors shall be provided for servicing the fan and, where necessary, a drain shall be provided.
(4) Two or more operations shall not be connected to the same exhaust system where the combination of substances removed may constitute a fire, explosion, or chemical reaction hazard in the duct system.
(5) The ventilation rate of every mechanical ventilation system used to prevent harmful exposure shall be tested after initial installation, alterations, or maintenance, and at least annually, by means of a pitot traverse of the exhaust duct or equivalent measurements. Records of these tests shall be retained for at least five years.
(b) Duration of Operations. The exhaust system shall be in operation continually during all operations for which it is designed. The system shall continue to operate for some time after the cessation of said operations, the length of time to depend upon the individual circumstances and effectiveness of the ventilation system.
(c) Disposal of Exhaust Materials.
(1) The air outlet from every dust separator/collector and the dusts, fumes, mists, vapors or gases collected by an exhaust or ventilating system shall discharge to the outside atmosphere, provided that the exhaust system shall discharge to the outer air in such a manner that it will not
cause a harmful exposure in any accessible workplace. Collecting systems which return air to work areas may be used if contaminants which accumulate in the work area do not result in harmful exposure to employees.
(2) The air exhausted from blast-cleaning equipment, grinding, buffing, polishing equipment and all other equipment requiring exhausting of dust or particulate shall be discharged through dust-collecting equipment. Dust and refuse discharged from an exhaust system shall be disposed of in such a manner that it will not result in harmful exposure to employees. (continued)