40 CFR § 63.7321 - When must I conduct subsequent performance tests?

---
identifier: "/us/cfr/t40/s63.7321"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 63.7321 - When must I conduct subsequent performance tests?"
title_number: 40
title_name: "Protection of Environment"
section_number: "63.7321"
section_name: "When must I conduct subsequent performance tests?"
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: "2026-04-05"
last_updated: "2026-04-05"
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"
---


# 63.7321 When must I conduct subsequent performance tests?

(a) For each control device subject to an emission limit for particulate matter in § 63.7290(a), you must conduct subsequent performance tests no less frequently than once every 5 years or at the beginning of each term of your title V operating permit, whichever is less.

(b) For each source subject to emission limits in §§ 63.7290(b) through (d), 63.7296(c) through (f), 63.7297(a) through (d), and 63.7298(a) through (e) for capture systems and control devices applied to pushing emissions, battery stacks, HNR HRSG main stacks, and HNR HRSG bypass/waste heat stacks sources, respectively, you must conduct subsequent performance tests once every five years.

[89 FR 55745, July 5, 2024]