---
kind: "section"
citation: "40 C.F.R. § 1065.260"
title: "40"
number: "1065.260"
heading: "Flame-ionization detector."
url: "https://uscodex.org/cfr/40/1065.260"
---

# §1065.260. Flame-ionization detector.

- (a) **Application.** Use a flame-ionization detector (FID) analyzer to measure hydrocarbon concentrations in raw or diluted exhaust for either batch or continuous sampling. Determine hydrocarbon concentrations on a carbon number basis of one, C1. For measuring THC or THCE you must use a FID analyzer. For measuring CH4 you must meet the requirements of [paragraph (g)](#g) of this section. See [subpart I](/cfr/40/subpartI.md) of this part for special provisions that apply to measuring hydrocarbons when testing with oxygenated fuels.
- (b) **Component requirements.** We recommend that you use a FID analyzer that meets the specifications in Table 1 of [§ 1065.205](/cfr/40/1065.205.md). Note that your FID-based system for measuring THC, THCE, or CH4 must meet all the verifications for hydrocarbon measurement in [subpart D](/cfr/40/subpartD.md) of this part, and it must also meet the linearity verification in [§ 1065.307](/cfr/40/1065.307.md).
- (c) **Heated FID analyzers.** For measuring THC or THCE from compression-ignition engines, two-stroke spark-ignition engines, and four-stroke spark-ignition engines at or below 19 kW, you must use heated FID analyzers that maintain all surfaces that are exposed to emissions at a temperature of (191 ±11) °C.
- (d) **FID fuel and burner air.** Use FID fuel and burner air that meet the specifications of [§ 1065.750](/cfr/40/1065.750.md). Do not allow the FID fuel and burner air to mix before entering the FID analyzer to ensure that the FID analyzer operates with a diffusion flame and not a premixed flame.
- (e) **NMHC and NMOG.** For demonstrating compliance with NMHC standards, you may either measure THC and determine NMHC mass as described in [§ 1065.660(b)(1)](/cfr/40/1065.660.md?p=b-1), or you may measure THC and CH4 and determine NMHC as described in § [1065.660(b)(2)](/cfr/40/1065.660.md?p=b-2) or [(3)](/cfr/40/1065.660.md?p=b-3). You may also use the additive method in [§ 1065.660(b)(4)](/cfr/40/1065.660.md?p=b-4) for natural gas-fueled engines as described in [§ 1065.266](/cfr/40/1065.266.md). See [40 CFR 1066.635](/cfr/40/1066.635.md) for methods to demonstrate compliance with NMOG standards for vehicle testing.
- (f) **NMNEHC.** For demonstrating compliance with NMNEHC standards, you may either measure NMHC or determine NMNEHC mass as described in [§ 1065.660(c)(1)](/cfr/40/1065.660.md?p=c-1), you may measure THC, CH4, and C2H6 and determine NMNEHC as described in [§ 1065.660(c)(2)](/cfr/40/1065.660.md?p=c-2), or you may use the additive method in [§ 1065.660(c)(3)](/cfr/40/1065.660.md?p=c-3).
- (g) **CH—** 4. For reporting CH4 or for demonstrating compliance with CH4 standards, you may use a FID analyzer with a nonmethane cutter as described in [§ 1065.265](/cfr/40/1065.265.md) or you may use a GC-FID as described in [§ 1065.267](/cfr/40/1065.267.md). Determine CH4 as described in [§ 1065.660(d)](/cfr/40/1065.660.md?p=d).

## Notes

### Amendments

[76 FR 57442, Sept. 15, 2011, as amended at 79 FR 23761, Apr. 28, 2014; 81 FR 74163, Oct. 25, 2016; 86 FR 34536, June 29, 2021; 88 FR 4672, Jan. 24, 2023]

### Authority

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

### Source

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

### Amendments

[76 FR 57442, Sept. 15, 2011, as amended at 79 FR 23761, Apr. 28, 2014; 81 FR 74163, Oct. 25, 2016; 86 FR 34536, June 29, 2021; 88 FR 4672, Jan. 24, 2023]