The quantities to be measured under the test conditions described below, are the A-weighted sound levels for “fast” or “slow” meter response as defined in the American National Standard S1.4-1971.
authority: Noise Control Act of 1972, sec. 17(a), 86 Stat. 1234 (
42 U.S.C. 4916(a))
source: 45 FR 1263, Jan. 4, 1980, unless otherwise noted.
cite as: 40 CFR 201.21