# NTSB Safety Recommendation P-72-033

**Citation:** P-72-033  
**Type / status:** guidance / guidance  
**Agency:** National Transportation Safety Board  
**Effective:** 1972-06-08  
**Published:** 1972-06-08

THE NTSB RECOMMENDS THAT THE EQUITABLE GAS COMPANY: DEVELOP STANDARDS FOR THE DESIGN OF TYPICAL REGULATOR STATION INSTALLATIONS FOR VARIOUS TYPES OF SERVICE.

## Document text

NTSB safety recommendation P-72-033.

THE NTSB RECOMMENDS THAT THE EQUITABLE GAS COMPANY: DEVELOP STANDARDS FOR THE DESIGN OF TYPICAL REGULATOR STATION INSTALLATIONS FOR VARIOUS TYPES OF SERVICE.

Priority: CLASS II

Overall Status: Closed - Acceptable Action

Issued Date: 1972-06-08

Adopted Date: 1972-05-25

Overall Date Closed: 1975-12-30

Synopsis: ON NOVEMBER 17, 1971, WHILE IN THE PROCESS OF REVAMPING A REGULATOR STATION, EMPLOYEES OF THE EQUITABLE GAS COMPANY WERE ATTEMPTING TO REPLACE A VALVE ON THE LOW-PRESSURE SIDE OF A REGULATOR IN A VAULT WITHOUT FIRST STOPPING THE FLOW OF GAS. TWO MEN WORKING IN THE VAULT WERE OVERCOME BY GAS LEAKING INTO THE VAULT. FOUR OTHERS ALSO WERE OVERCOME ATTEMPTING TO RESCUE THE FIRST TWO. ALL SIX MEN DIED OF ASPHYXIATION. THREE OTHER MEN ALSO WERE INJURED.

Probable Cause: Inhalation of natural gas released into a vault where two men were attempting to change a valve in the vault without first stopping the flow of gas.

Ntsbnumber: PLD72XR004

Report Number: PAR-72-02

Addressee Name: Equitable Gas Company

Addressee Status: Closed--No Longer Applicable

Addressee Date Closed: 1975-12-30

Addressee Acronym: EQT

Addressee Organization Type: P-Private Industry

Communication Date: 1972-12-21

Communication Type: Official Correspondence

Communication Contents: LTR FROM EQUITABLE: DESIGN STANDARDS ARE BEING DEVELOPED TO ENCOMPASS VIRTUALLY EVERY FACILITY INSTALLATION, INCLUDING REGULATOR DESIGN.

Addressee Acronym: EQT

Addressee Organization Type: P-Private Industry

Communication Date: 1978-06-09

Communication Type: Official Correspondence

## Provenance

- Official: Yes
- Source: <https://data.ntsb.gov/carol-main-public/sr-details/P-72-033>
- Source ID: `ntsb-pipeline`
- SHA-256: `67ad913d4507f212722a5826d0d9f5418b2c9db78561ee603354431fc357647c`
- Retrieved: 2026-08-20T04:57:24.741Z
- Exported: 2026-08-24T01:21:04.536Z
- Document slug: `ntsb-recommendation-p-72-033`

### Source metadata

```json
{
  "recordKind": "ntsb_safety_recommendation",
  "safetyRecommendationNumber": "P-72-033",
  "recommendationMode": "Pipeline",
  "topicMode": "Pipeline",
  "ntsbNumber": "PLD72XR004",
  "priority": "CLASS II",
  "overallStatus": "Closed - Acceptable Action",
  "overallStatusAcronym": "CAA",
  "overallDateClosed": "1975-12-30",
  "lastModifiedDate": "2016-11-15",
  "reportNumber": "PAR-72-02",
  "reportUrl": "https://www.ntsb.gov/investigations/Pages/PLD72XR004.aspx",
  "transmittalLetterUrl": "http://www.ntsb.gov/safety/safety-recs/recletters/P72_25_33.pdf",
  "addressees": [
    {
      "addresseeName": "Equitable Gas Company",
      "addresseeStatusAcronym": "CNLA",
      "addresseeStatus": "Closed--No Longer Applicable",
      "addresseeDateClosed": "1975-12-30",
      "addresseeDetails": [
        {
          "addresseeAcronym": "EQT",
          "addresseeOrganizationType": "P-Private Industry",
          "isFromNtsb": false,
          "communicationDate": "1972-12-21",
          "communicationType": "Official Correspondence",
          "communicationContents": "LTR FROM EQUITABLE: DESIGN STANDARDS ARE BEING DEVELOPED TO ENCOMPASS VIRTUALLY EVERY FACILITY INSTALLATION, INCLUDING REGULATOR DESIGN."
        },
        {
          "addresseeAcronym": "EQT",
          "addresseeOrganizationType": "P-Private Industry",
          "isFromNtsb": true,
          "communicationDate": "1978-06-09",
          "communicationType": "Official Correspondence",
          "communicationContents": ""
        }
      ]
    }
  ],
  "jurisdiction": "US"
}
```