---
kind: "section"
citation: "40 C.F.R. § 1065.265"
title: "40"
number: "1065.265"
heading: "Nonmethane cutter."
url: "https://uscodex.org/cfr/40/1065.265"
---

# §1065.265. Nonmethane cutter.

- (a) **Application.** You may use a nonmethane cutter to measure CH4 with a FID analyzer. A nonmethane cutter oxidizes all nonmethane hydrocarbons to CO2 and H2O. You may use a nonmethane cutter for raw or diluted exhaust for batch or continuous sampling.
- (b) **System performance.** Determine nonmethane-cutter performance as described in [§ 1065.365](/cfr/40/1065.365.md) and use the results to calculate CH4 or NMHC emissions in [§ 1065.660](/cfr/40/1065.660.md).
- (c) **Configuration.** Configure the nonmethane cutter with a bypass line if it is needed for the verification described in [§ 1065.365](/cfr/40/1065.365.md).
- (d) **Optimization.** You may optimize a nonmethane cutter to maximize the penetration of CH4 and the oxidation of all other hydrocarbons. You may humidify a sample and you may dilute a sample with purified air or oxygen (O2) upstream of the nonmethane cutter to optimize its performance. You must account for any sample humidification and dilution in emission calculations.

## Notes

### Amendments

[70 FR 40516, July 13, 2005, as amended at 73 FR 37300, June 30, 2008; 76 FR 57442, Sept. 15, 2011]

### Authority

Authority: 42 U.S.C. 7401-7671q.

### Source

Source: 70 FR 40516, July 13, 2005, unless otherwise noted.

### Amendments

[70 FR 40516, July 13, 2005, as amended at 73 FR 37300, June 30, 2008; 76 FR 57442, Sept. 15, 2011]