40 CFR § 57.401 - General requirements.

---
identifier: "/us/cfr/t40/s57.401"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 57.401 - General requirements."
title_number: 40
title_name: "Protection of Environment"
section_number: "57.401"
section_name: "General requirements."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "C"
subchapter_name: "AIR PROGRAMS"
part_number: "57"
part_name: "PRIMARY NONFERROUS SMELTER ORDERS"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "Secs. 110, 114, 119, 301, Clean Air Act, as amended (42 U.S.C. 7410, 7414, 7419, and 7601); sec. 406 of Pub. L. 95-95."
regulatory_source: "50 FR 6448, Feb. 15, 1985, unless otherwise noted."
cfr_part: "57"
---


# 57.401 General requirements.

Except as provided in subpart E, each NSO shall require the smelter owner to prevent all violations of the NAAQS in the smelter's designated liability area (DLA) through the operation of an approved supplementary control system (SCS).