40 CFR § 63.5121 - What operating limits must I meet?

---
identifier: "/us/cfr/t40/s63.5121"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 63.5121 - What operating limits must I meet?"
title_number: 40
title_name: "Protection of Environment"
section_number: "63.5121"
section_name: "What operating limits must I meet?"
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "C"
subchapter_name: "AIR PROGRAMS"
part_number: "63"
part_name: "NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "42 U.S.C. 7401"
regulatory_source: "57 FR 61992, Dec. 29, 1992, unless otherwise noted."
cfr_part: "63"
---


# 63.5121 What operating limits must I meet?

(a) Except as provided in paragraph (b) of this section, for any coil coating line for which you use an add-on control device, unless you use a solvent recovery system and conduct a liquid-liquid material balance according to § 63.5170(e)(1), you must meet the applicable operating limits specified in Table 1 to this subpart. You must establish the operating limits during performance tests according to the requirements in § 63.5160(d)(3) and Table 1 to § 63.5160. You must meet the operating limits established during the most recent performance test required in § 63.5160 at all times after you establish them.

(b) If you use an add-on control device other than those listed in Table 1 to this subpart, or wish to monitor an alternative parameter and comply with a different operating limit, you must apply to the Administrator for approval of alternative monitoring under § 63.8(f).

[67 FR 39812, June 10, 2002, as amended at 85 FR 10862, Feb. 25, 2020]