---
kind: "section"
citation: "40 C.F.R. § 60.6525"
title: "40"
number: "60.6525"
heading: "What schedule must I follow for the stack testing?"
url: "https://uscodex.org/cfr/40/60.6525"
---

# §60.6525. What schedule must I follow for the stack testing?

- (a) Conduct initial stack tests for sulfur dioxide, nitrogen oxides, and each of the pollutants listed in [§ 60.6515](/cfr/40/60.6515.md) by 180 days after your final compliance date.
- (b) Conduct annual stack tests for each of the pollutants listed in [§ 60.6515](/cfr/40/60.6515.md) after the initial stack test. Conduct each annual stack test no less than 9 calendar months and no more than 15 calendar months following the previous performance test, except as specified in [§ 60.6540](/cfr/40/60.6540.md) of this section. You must complete five performance tests in each 5-year calendar period.

## Notes

### Source

Source: 91 FR 11860, Mar. 10, 2026, unless otherwise noted.

### Authority

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

### Source

Source: 36 FR 24877, Dec. 23, 1971, unless otherwise noted.