# Heating Value Determination and Records

**Citation:** COMAR 20.55.08.05  
**Type / status:** regulation / current  
**Agency:** Maryland Public Service Commission  
**Effective:** Not stated  
**Published:** Not stated

Maryland pipeline-safety provision COMAR 20.55.08.05, Heating Value Determination and Records.

## Document text

A. Calorimeter or Chromatograph.

(1) The utility shall provide, or designate, a calorimeter, chromatograph, or other device of a type acceptable to the Commission for the regular determination of the heating value of the gas sold.

(2) Installation. The equipment used to determine heating value shall be installed in a suitably located testing station acceptable to the Commission and subject to its inspection.

(3) Accuracy. The accuracy of all equipment used to determine heating value, as well as the method of making heating value tests, shall be acceptable to the Commission. Recording calorimeters or other equipment used to determine heating value shall be tested with a standard gas at least once each month.

(4) Records. Heating value test records shall be preserved for at least 3 years.

B. LP-Air. The utility shall determine the heating value of LP-Air once each hour when LP-Air is being injected into the distribution system.

C. Natural Gas and LPG. The utility shall determine the heating value of natural gas and undiluted LPG at least once each month, except that utilities selling gas subject to a thermal adjustment shall determine the heating value at least twice each day and shall make the tests during the period of the morning and afternoon peak demands.

## Provenance

- Official: Yes
- Source: <https://regs.maryland.gov/us/md/exec/comar/20.55.08.05>
- Source ID: `maryland-comar`
- SHA-256: `112d18fc821d030a06c778276572d7c1bb6f42e816bb839f7f2a3aa890806811`
- Retrieved: 2026-08-20T08:47:37.108Z
- Exported: 2026-08-23T11:40:20.343Z
- Document slug: `md-comar-20-55-08-05`

### Source metadata

```json
{
  "jurisdiction": "US-MD",
  "commodity": [
    "natural-gas",
    "other-gas"
  ],
  "legalScope": "Bounded Maryland PSC pipeline-safety rules in COMAR 20.55-20.57.",
  "applicabilityCaveat": "Maryland PSC enforcement under PHMSA certification is limited to intrastate gas and hazardous-liquid pipeline operators and applicable LPG systems. PHMSA retains inspection and enforcement responsibility for interstate gas and hazardous-liquid pipelines. Coverage also depends on operator class, gas-company or master-meter status, facility and commodity definitions, exemptions, waivers, and federal preemption.",
  "incorporationCaveat": "Maryland provisions use both fixed editions of private or federal guidance and prospective phrases such as 'as amended' for federal statutes and 49 CFR. This connector preserves the consolidated Maryland text retrieved on the stated date but does not infer that every later federal amendment is incorporated for every legal purpose. Verify the controlling Maryland incorporation rule, federal edition, and event date.",
  "publicationCaveat": "The Library of Maryland Regulations is the official consolidated access system, but the Maryland Register and filed rulemaking record control adoption history. Administrative-history notes are evidence aids, not substitutes for the promulgation record. The PSC program description is dated September 2011 and is used only to corroborate program scope, not current rule text.",
  "rightsCaveat": "Official Maryland and federal legal-source captures are preserved with attribution and hashes. State presentation, seals, site software, and incorporated private standards may carry separate rights; incorporated standards are referenced but not reproduced by this connector.",
  "references": [],
  "region": "MD"
}
```