---
kind: "section"
citation: "40 C.F.R. § 60.6530"
title: "40"
number: "60.6530"
heading: "What procedures and test methods must I use to stack test?"
url: "https://uscodex.org/cfr/40/60.6530"
---

# §60.6530. What procedures and test methods must I use to stack test?

- (a) Follow Table 5 to [Subpart WWWW](/cfr/40/subpartWWWW.md) to establish the procedures and test methods, and other specific testing requirements for the different pollutants.
- (b) Stack tests for all the pollutants must consist of at least three test runs, as specified in [§ 60.8](/cfr/40/60.8.md), conducted under representative full load operating conditions. For particulate matter, opacity, cadmium, lead, mercury, hydrogen chloride, and dioxins/furans, use the arithmetic average of the pollutant emission concentrations from the three test runs to determine compliance with the applicable emission limits in Table 3 to Subpart WWWW. For fugitive ash, use the average duration of visible emissions per hour as calculated from three 1-hr observations to determine compliance with the emission limits in Table 2 to Subpart WWWW.
- (c) Obtain an oxygen (or carbon dioxide) measurement at the same time as your pollutant measurements to determine diluent gas levels, as specified in [§ 60.6465](/cfr/40/60.6465.md).
- (d) You may request that compliance with emission limits be determined using carbon dioxide measurements corrected to an equivalent of 7 percent oxygen. The relationship between oxygen and carbon dioxide levels for the affected facility shall be established as specified in [§ 60.6485](/cfr/40/60.6485.md).
- (e) Use equation 1 in [§ 60.6680(a)](/cfr/40/60.6680.md?p=a) to calculate emission levels at 7 percent oxygen (or an equivalent carbon dioxide basis). See the individual test methods in Table 5 to [Subpart WWWW](/cfr/40/subpartWWWW.md) for other required equations.

## 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.