# Gas Leak Surveys

**Citation:** COMAR 20.56.01.07  
**Type / status:** regulation / current  
**Agency:** Maryland Public Service Commission  
**Effective:** Not stated  
**Published:** Not stated

Maryland pipeline-safety provision COMAR 20.56.01.07, Gas Leak Surveys.

## Document text

A. Frequency of Leak Surveys. Each owner shall conduct a gas leak survey of a LPG pipeline system in accordance with the following schedule:

(1) At least once each calendar year, at intervals not exceeding 15 months, for a pipeline located in a business district or place of public assembly;

(2) At least once every 3 calendar years, at intervals not exceeding 39 months, for a pipeline made of cast iron, ductile iron, and cathodically unprotected steel; or

(3) At least once every 5 calendar years, at intervals not exceeding 63 months, for all other types of pipelines.

B. Testing Methods.

(1) Each owner shall establish written procedures for conducting gas leak surveys as specified in this chapter.

(2) Acceptable methods for owners conducting gas leak surveys, as described in the GPTC Guide for Gas Transmission and Distribution Piping Systems, include:

(a) Subsurface gas detector survey, including bar hole surveys;

(b) Bubble leakage test for pipelines exposed to the atmosphere; or

(c) Pressure drop test.

(3) In addition to the acceptable methods listed in §B(2) of this regulation, other survey and test methods that have been tested and proven to be at least equal to the methods listed in §B(2) of this regulation and approved by the Commission may be used to meet the requirements of §B(1) of this regulation.

C. A leak or leaks discovered by a gas leak survey conducted pursuant to this regulation shall be classified, and the appropriate action taken as described in the GPTC Guide For Gas Transmission and Distribution Piping Systems.

D. Field Operations.

(1) An owner shall conduct a leakage survey on each new or replaced service line before the line is placed in service, but after backfilling and a reasonable period of gas pressurizing.

(2) After a leak repair, an owner shall conduct a gas leakage survey in accordance with §B of this regulation.

E. Records of Leak Surveys.

(1) An owner shall maintain a record of each leak survey listing by location and date for the following:

(a) Number of leaks detected;

(b) Severity of each leak; and

(c) Action taken to repair each leak.

(2) An owner shall maintain the records required under §E(1) of this regulation as long as the segment of pipeline involved remains in service.

## Provenance

- Official: Yes
- Source: <https://regs.maryland.gov/us/md/exec/comar/20.56.01.07>
- Source ID: `maryland-comar`
- SHA-256: `ac33070a5a6defef302a0787c65a022e02363fc682ca666ddf43a8ce41cb7169`
- Retrieved: 2026-08-20T08:47:37.108Z
- Exported: 2026-08-22T15:36:33.856Z
- Document slug: `md-comar-20-56-01-07`

### Source metadata

```json
{
  "jurisdiction": "US-MD",
  "commodity": [
    "liquefied-petroleum-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"
}
```