# NTSB Safety Recommendation P-72-006

**Citation:** P-72-006  
**Type / status:** guidance / guidance  
**Agency:** National Transportation Safety Board  
**Effective:** 1971-12-08  
**Published:** 1971-12-08

THE NTSB RECOMMENDS THAT: THE COLONIAL PIPELINE COMPANY MEET WITH APPROPRIATE STATE SAFETY AGENCIES TO COORDINATE SAFE WORKING RULES AND REGULATIONS AND HOLD PERIODIC PIPELINE SAFETY MEETINGS WITH FIRE DEPARTMENTS AND OTHER INTERESTED AGENCIES, TO FAMILARIZE THEIR PERSONNEL WITH BASIC PIPELINE OPERATIONS, MATERIALS PUMPED, HAZARDS ENCOUNTERED, AND THE PROCEDURES TO BE FOLLOWED WHEN ENCOUNTERING PIPELINE LEAKS OR OTHE

## Document text

NTSB safety recommendation P-72-006.

THE NTSB RECOMMENDS THAT: THE COLONIAL PIPELINE COMPANY MEET WITH APPROPRIATE STATE SAFETY AGENCIES TO COORDINATE SAFE WORKING RULES AND REGULATIONS AND HOLD PERIODIC PIPELINE SAFETY MEETINGS WITH FIRE DEPARTMENTS AND OTHER INTERESTED AGENCIES, TO FAMILARIZE THEIR PERSONNEL WITH BASIC PIPELINE OPERATIONS, MATERIALS PUMPED, HAZARDS ENCOUNTERED, AND THE PROCEDURES TO BE FOLLOWED WHEN ENCOUNTERING PIPELINE LEAKS OR OTHER EMERGENCIES.

Priority: CLASS II

Overall Status: Closed - Acceptable Action

Issued Date: 1971-12-08

Adopted Date: 1971-12-08

Overall Date Closed: 1975-12-30

Synopsis: ON SEPTEMBER 2, 1970, A PIPELINE LEAK OCCURRED IN THE COLONIAL PIPELINE SYSTEM NEAR JACKSONVILLE, MARYLAND. CONTRACTORS WORKED CONTINUOUSLY FOR 20 HOURS TO FIND THE LEAK, AND ON THE NEXT DAY AN EXPLOSION OCCURRED FOLLOWED BY A FIRE. THERE WERE NO FATALITIES, BUT FIVE WORKMEN WERE BURNED.

Probable Cause: The National Transportation Safety Board determines that the probable cause of the leak was a flaw of undetermined origin in the pipe wall, crater-like in appearance, wide at the surface and narrowing down to a thin metal membrane, which failed after a period of constantly fluctuating pumping pressures. The probable cause of the explosion and fires was the ingestion of the gasoline vapor-rich atmosphere by a diesel engine which resulted in the speeding up and backfiring of the engine, igniting the atmosphere.

Ntsbnumber: DCA70MP003

Report Number: PAR-71-02

Addressee Name: Colonial Pipeline Company

Addressee Status: Closed--No Longer Applicable

Addressee Date Closed: 1975-12-30

Addressee Organization Type: P-Private Industry

Communication Date: 1972-05-24

Communication Type: Official Correspondence

Communication Contents: LETTER FROM COLONIAL: IT HAS ALWAYS BEEN THE PRACTICE OF COLONIAL TO ESTABLISH LIAISON WITH THE RESIDENTS ALONG THE RIGHT OF WAY, WITH FIRE AND POLICE DEPARTMENTS AND ALL OTHER INTERESTED AGENCIES. WE CAN ASSURE YOU THAT WE ARE GIVING SERIOUS ATTENTION TO THIS CONTINUING PROBLEM.

## Provenance

- Official: Yes
- Source: <https://data.ntsb.gov/carol-main-public/sr-details/P-72-006>
- Source ID: `ntsb-pipeline`
- SHA-256: `ef0c69b1266eea923dee3ff6995bb4632a0b9808e16ba15a7a5addd27550c0b1`
- Retrieved: 2026-08-20T04:57:24.741Z
- Exported: 2026-08-25T17:42:20.999Z
- Document slug: `ntsb-recommendation-p-72-006`

### Source metadata

```json
{
  "recordKind": "ntsb_safety_recommendation",
  "safetyRecommendationNumber": "P-72-006",
  "recommendationMode": "Pipeline",
  "topicMode": "Pipeline",
  "ntsbNumber": "DCA70MP003",
  "priority": "CLASS II",
  "overallStatus": "Closed - Acceptable Action",
  "overallStatusAcronym": "CAA",
  "overallDateClosed": "1975-12-30",
  "lastModifiedDate": "2016-11-15",
  "reportNumber": "PAR-71-02",
  "reportUrl": "https://www.ntsb.gov/investigations/Pages/DCA70MP003.aspx",
  "transmittalLetterUrl": "http://www.ntsb.gov/safety/safety-recs/recletters/P72_1_7.pdf",
  "addressees": [
    {
      "addresseeName": "Colonial Pipeline Company",
      "addresseeStatusAcronym": "CNLA",
      "addresseeStatus": "Closed--No Longer Applicable",
      "addresseeDateClosed": "1975-12-30",
      "addresseeDetails": [
        {
          "addresseeAcronym": null,
          "addresseeOrganizationType": "P-Private Industry",
          "isFromNtsb": false,
          "communicationDate": "1972-05-24",
          "communicationType": "Official Correspondence",
          "communicationContents": "LETTER FROM COLONIAL: IT HAS ALWAYS BEEN THE PRACTICE OF COLONIAL TO ESTABLISH LIAISON WITH THE RESIDENTS ALONG THE RIGHT OF WAY, WITH FIRE AND POLICE DEPARTMENTS AND ALL OTHER INTERESTED AGENCIES. WE CAN ASSURE YOU THAT WE ARE GIVING SERIOUS ATTENTION TO THIS CONTINUING PROBLEM."
        }
      ]
    }
  ],
  "jurisdiction": "US"
}
```