§ 70.500 - Definitions.

As used in this subpart F, the term:

(a) dBA means noise level in decibels, relative to a reference level of 20 micro pascals, as measured by the use of an A-weighting and slow metering characteristic as specified in American National Standards Institute (ANSI), “Specification for Sound Level Meters,” S1.4-1971 (Type S2A).

(b) Noise exposure means a period of time during which the noise level is 90 or more dBA;

(c) Multiple noise exposure means the daily noise exposure is composed of two or more different noise levels;

(d) Noise level is the average dBA during a noise exposure; and,

(e) Qualified person means, as the context requires, an individual deemed qualified by the Secretary and designated by the operator to make tests and examinations required by this Act.

(f) Personal noise dosimeter means equipment worn by an individual, which performs noise level measurements along with exposure time measurements. The circuitry of the instrument is such that it automatically performs the computation of the multiple noise exposure specified in § 70.502.

(Sec. 101, Federal Mine Safety and Health Act of 1977, Pub. L. 91-173 as amended by Pub. L. 95-164, 91 Stat. 1291 (30 U.S.C. 811); sec. 301, Federal Mine Safety and Health Amendments Act of 1977, Pub. L. 95-164, 91 Stat. 1317 (U.S.C. 961)