---
kind: "section"
citation: "40 C.F.R. § 63.7321"
title: "40"
number: "63.7321"
heading: "When must I conduct subsequent performance tests?"
url: "https://uscodex.org/cfr/40/63.7321"
---

# §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)](/cfr/40/63.7290.md?p=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)](/cfr/40/63.7290.md?p=b..d), [63.7296(c) through (f)](/cfr/40/63.7296.md?p=c..f), [63.7297(a) through (d)](/cfr/40/63.7297.md?p=a..d), and [63.7298(a) through (e)](/cfr/40/63.7298.md?p=a..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.

## Notes

### Amendments

[89 FR 55745, July 5, 2024]

### Source

Source: 68 FR 18025, Apr. 14, 2003, unless otherwise noted.

### Authority

Authority: 42 U.S.C. 7401 et seq.

### Source

Source: 57 FR 61992, Dec. 29, 1992, unless otherwise noted.

### Amendments

[89 FR 55745, July 5, 2024]