---
kind: "section"
citation: "43 C.F.R. § 3175.125"
title: "43"
number: "3175.125"
heading: "Calculation of heating value and volume"
url: "https://uscodex.org/cfr/43/3175.125"
---

# §3175.125. Calculation of heating value and volume

- (a) The heating value of the gas sampled must be calculated as follows:
  - (1) Gross heating value is defined by API 14.5, Subsection 3.7 (incorporated by reference, see [§ 3175.30](/cfr/43/3175.30.md)) and must be calculated under API 14.5, Subsection 7.1 (incorporated by reference, see [§ 3175.30](/cfr/43/3175.30.md)); and
  - (2) Real heating value must be calculated by dividing the gross heating value of the gas calculated under [paragraph (a)(1)](#a-1) of this section by the compressibility factor of the gas at 14.73 psia and 60 °F.
- (b) **Average heating value determination.**
  - (1) If a lease, unit PA, or CA has more than one FMP, the average heating value for the lease, unit PA, or CA for a reporting month must be the volume-weighted average of heating values, calculated as follows:
  - (2) If the effective date of a heating value for an FMP is other than the first day of the reporting month, the average heating value of the FMP must be the volume-weighted average of heating values, determined as follows:
- (c) The volume must be determined under [§ 3175.94](/cfr/43/3175.94.md) (mechanical recorders) or [§ 3175.103(c)](/cfr/43/3175.103.md?p=c) (EGM systems).

## Notes

### Source

Source: 81 FR 81609, Nov. 17, 2016, unless otherwise noted.

### Authority

Authority: 25 U.S.C. 396d and 2107; 30 U.S.C. 189, 306, 359, and 1751; and 43 U.S.C. 1732(b), 1733, and 1740.

### Source

Source: 81 FR 81421, Nov. 17, 2016, unless otherwise noted.