# NTSB Safety Recommendation P-79-029

**Citation:** P-79-029  
**Type / status:** guidance / guidance  
**Agency:** National Transportation Safety Board  
**Effective:** 1979-10-04  
**Published:** 1979-10-04

THE NTSB RECOMMENDS THAT THE AMERICAN GAS ASSOCIATION: ADVISE ITS MEMBER COMPANIES OF THE CIRCUMSTANCES OF THIS ACCIDENT AND OF THE PROMPT AND EFFECTIVE COORDINATION BETWEEN THE GAS COMPANY AND THE FIRE DEPARTMENT AND URGE THEM TO REVIEW THEIR EMERGENCY PRACTICES AND PROCEDURES, PARTICULARLY THOSE CONCERNING EVACUATION AND LIAISON WITH FIRE AND POLICE DEPARTMENTS TO INSURE THAT COORDINATION IS PLANNED ADEQUATELY FOR 

## Document text

NTSB safety recommendation P-79-029.

THE NTSB RECOMMENDS THAT THE AMERICAN GAS ASSOCIATION: ADVISE ITS MEMBER COMPANIES OF THE CIRCUMSTANCES OF THIS ACCIDENT AND OF THE PROMPT AND EFFECTIVE COORDINATION BETWEEN THE GAS COMPANY AND THE FIRE DEPARTMENT AND URGE THEM TO REVIEW THEIR EMERGENCY PRACTICES AND PROCEDURES, PARTICULARLY THOSE CONCERNING EVACUATION AND LIAISON WITH FIRE AND POLICE DEPARTMENTS TO INSURE THAT COORDINATION IS PLANNED ADEQUATELY FOR SIMILAR ACCIDENTS.

Priority: CLASS II

Overall Status: Closed - Acceptable Action

Issued Date: 1979-10-04

Adopted Date: 1979-09-27

Overall Date Closed: 1983-05-04

Synopsis: ON MAY 11, 1979, TWO ALMOST SIMULTANEOUS EXPLOSIONS AND AN ENSUING FIRE DESTROYED THREE BUILDINGS NEAR THE INTERSECTION OF TACONY AND MARGARET STREETS IN PHILADELPHIA, PENNSYLVANIA. SEVEN PERSONS, INCLUDING A PHILADELPHIA GAS WORKS EMPLOYEE, WERE KILLED, 19 PERSONS WERE INJURED, AND SEVERAL ADJACENT ROWHOUSES WERE DAMAGED. THE EXPLOSIONS ALSO CAUSED A SECTION OF MARGARET STREET TO COLLAPSE, EXPOSING A LARGE CAVERN UNDERNEATH THE PAVED SURFACE.

Ntsbnumber: DCA79MP015

Report Number: PAR-79-03

Addressee Name: American Gas Association

Addressee Status: Closed--No Longer Applicable

Addressee Date Closed: 1983-05-04

Addressee Acronym: AGA

Addressee Organization Type: A-Associations

Communication Date: 1983-02-01

Communication Type: Official Correspondence

Communication Contents: AMERICAN GAS ASSOCIATION (AGA) LETTER: AGA CORRESPONDENCE TO MEMBER COMPANY DELEGATES DATED OCTOBER 31, 1979, REFERS TO SAFETY RECOMMENDATION P-79-29 CONCERNING PHILADELPHIA GAS WORKS.

Addressee Acronym: AGA

Addressee Organization Type: A-Associations

Communication Date: 1983-05-04

Communication Type: Official Correspondence

Addressee Acronym: AGA

Addressee Organization Type: A-Associations

Communication Date: 1982-10-05

Communication Type: Official Correspondence

## Provenance

- Official: Yes
- Source: <https://data.ntsb.gov/carol-main-public/sr-details/P-79-029>
- Source ID: `ntsb-pipeline`
- SHA-256: `507a279587350011e0cefc94b8e96a41c621a251838202e5cfc086ee7e4a74d4`
- Retrieved: 2026-08-20T04:57:24.741Z
- Exported: 2026-08-22T19:31:03.553Z
- Document slug: `ntsb-recommendation-p-79-029`

### Source metadata

```json
{
  "recordKind": "ntsb_safety_recommendation",
  "safetyRecommendationNumber": "P-79-029",
  "recommendationMode": "Pipeline",
  "topicMode": "Pipeline",
  "ntsbNumber": "DCA79MP015",
  "priority": "CLASS II",
  "overallStatus": "Closed - Acceptable Action",
  "overallStatusAcronym": "CAA",
  "overallDateClosed": "1983-05-04",
  "lastModifiedDate": "2016-11-15",
  "reportNumber": "PAR-79-03",
  "reportUrl": "https://www.ntsb.gov/investigations/Pages/DCA79MP015.aspx",
  "transmittalLetterUrl": "http://www.ntsb.gov/safety/safety-recs/recletters/P79_29.pdf",
  "addressees": [
    {
      "addresseeName": "American Gas Association",
      "addresseeStatusAcronym": "CNLA",
      "addresseeStatus": "Closed--No Longer Applicable",
      "addresseeDateClosed": "1983-05-04",
      "addresseeDetails": [
        {
          "addresseeAcronym": "AGA",
          "addresseeOrganizationType": "A-Associations",
          "isFromNtsb": false,
          "communicationDate": "1983-02-01",
          "communicationType": "Official Correspondence",
          "communicationContents": "AMERICAN GAS ASSOCIATION (AGA) LETTER:  AGA CORRESPONDENCE TO MEMBER COMPANY DELEGATES DATED OCTOBER 31, 1979, REFERS TO SAFETY RECOMMENDATION P-79-29 CONCERNING PHILADELPHIA GAS WORKS."
        },
        {
          "addresseeAcronym": "AGA",
          "addresseeOrganizationType": "A-Associations",
          "isFromNtsb": true,
          "communicationDate": "1983-05-04",
          "communicationType": "Official Correspondence",
          "communicationContents": ""
        },
        {
          "addresseeAcronym": "AGA",
          "addresseeOrganizationType": "A-Associations",
          "isFromNtsb": true,
          "communicationDate": "1982-10-05",
          "communicationType": "Official Correspondence",
          "communicationContents": ""
        }
      ]
    }
  ],
  "jurisdiction": "US"
}
```