part_subject: "NOISE EMISSION STANDARDS FOR TRANSPORTATION EQUIPMENT; INTERSTATE RAIL CARRIERS"
subpart_code: "C"
subpart_subject: "Measurement Criteria"
section_number: "201.21"
section_subject: "Quantities measured."
cfr_reference: "40 CFR 201.21"
title_name: "Title 40"
title_subject: "Protection of Environment"
parts_covered: "Parts 190 to 259"
revised_date: "Revised as of July 1, 2019"
publication_date: "As of July 1, 2019"
contains_description: "Containing a codification of documents of general applicability and future effect"
publication_info: "Published by Office of the Federal Register National Archives and Records Administration as a Special Edition of the Federal Register"
---
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.