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Subchapter 7. General Industry Safety Orders
Group 15. Occupational Noise
Article 105. Control of Noise Exposure

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§5095. General.

(a) Scope and Application. Article 105 establishes requirements for controlling occupational exposures to noise. Agriculture, construction, and oil and gas well drilling and servicing operations are exempt from the provisions of Sections 5097 through 5100.

(b) Definitions.

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.

Audiogram. A chart, graph, or table resulting from an audiometric test showing an individual's hearing threshold levels as a function of frequency.

Audiologist. A professional, specializing in the study and rehabilitation of hearing, who is certified by the American Speech, Hearing and Language Association or licensed by a state board of examiners.

Baseline Audiogram. The audiogram against which future audiograms are compared.

Criterion Sound Level. A sound level of 90 decibels.

Decibel (dB). Unit of measurement of sound level.

dBA (Decibels-A-Weighted). A unit of measurement of sound level corrected to the A-weighted scale, as defined in ANSI S1.4-1971 (R1976), using a reference level of 20 micropascals (0.00002 Newton per square meter).

Hertz (Hz). Unit of measurement of frequency, numerically equal to cycles per second.

Medical Pathology. A disorder or disease. For purposes of this regulation, a condition or disease affecting the ear, which should be treated by a physician specialist.

Otolaryngologist. A physician specializing in diagnosis and treatment of disorders of the ear, nose and throat.

Representative Exposure. Measurements of an employee's noise dose or 8-hour time-weighted average sound level that the employer deems to be representative of exposures of other employees in the workplace.

Sound Level. Ten times the common logarithm of the ratio of the square of the measured A-weighted sound pressure to the square of the standard reference pressure of 20 micropascals. Unit: decibels (dB). For use with this regulation, SLOW time response, in accordance with ANSI S1.4-1971 (R1976), is required.

Sound Level Meter. An instrument for the measurement of sound level.

Appendix A
Appendix B
Appendix C
Appendix D
Appendix E
Appendix F

NOTE: Authority and reference cited: Section 142.3, Labor Code.


1. Repealer of Group 15 (Article 105, Sections 5095-5099) and new Group 15 (Article 105, Sections 5095-5100 and Appendices A-E) filed 6-28-82; effective thirtieth day thereafter (Register 82, No. 27). For prior history, see Register 72, No. 6.

2. Amendment filed 10-3-83; effective thirtieth day thereafter (Register 83, No. 41).

3. Amendment of group heading filed 6-3-97; operative 7-3-97 (Register 97, No. 23).

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