# NTSB Safety Recommendation P-73-025

**Citation:** P-73-025  
**Type / status:** guidance / guidance  
**Agency:** National Transportation Safety Board  
**Effective:** 1973-06-18  
**Published:** 1973-06-18

THE NTSB RECOMMENDS THAT: THE AMERICAN STANDARDS INSTITUTE SECTION COMMITTEE FOR LIQUID PETROLEUM TRANSPORTATION PIPING SYSTEMS (ANSI B31.4) INCLUDE IN ITS STANDARDS THE REQUIREMENT THAT CONSIDERATION BE GIVEN, DURING DESIGN AND INSTALLATION OF LIQUID PIPING SYSTEMS, TO AVOIDING FUTURE EXCAVATION DAMAGE.

## Document text

NTSB safety recommendation P-73-025.

THE NTSB RECOMMENDS THAT: THE AMERICAN STANDARDS INSTITUTE SECTION COMMITTEE FOR LIQUID PETROLEUM TRANSPORTATION PIPING SYSTEMS (ANSI B31.4) INCLUDE IN ITS STANDARDS THE REQUIREMENT THAT CONSIDERATION BE GIVEN, DURING DESIGN AND INSTALLATION OF LIQUID PIPING SYSTEMS, TO AVOIDING FUTURE EXCAVATION DAMAGE.

Priority: CLASS II

Overall Status: Closed - Acceptable Action

Issued Date: 1973-06-18

Adopted Date: 1973-06-07

Overall Date Closed: 1983-02-14

Synopsis: "SPECIAL STUDY - PREVENTION OF DAMAGE TO PIPELINES." THIS SPECIAL STUDY CONCERNS DAMAGE TO GAS AND LIQUID PIPELINES CAUSED BY EXCAVATION AND CONSTRUCTION ACTIVITIES, INCLUDING BLASTING.

Ntsbnumber: 80571

Report Number: PSS-73-01

Addressee Name: American National Standards Institute

Addressee Status: Closed--No Longer Applicable

Addressee Date Closed: 1983-02-14

Addressee Acronym: ANSI

Addressee Organization Type: A-Associations

Communication Date: 1982-12-20

Communication Type: Official Correspondence

Communication Contents: AMERICAN SOCIETY OF MECHANICAL ENGINEERS (ASME) LETTER: THIS WAS REFERRED BY ANSI TO ASME FOR RESPONSE SINCE ASME IS PUBLISHER OF B31.4 CODE. THE FOLLOWING NEW ADDITIONS WERE MADE TO THE CODE TO INCORPORATE SOME OF THE SUGGESTIONS MADE BY NTSB: (1) TABLE 434.6(A) MINIMUM COVER FOR BURIED PIPELINES. (2) 434.14 OFFSHORE AND INLAND COASTAL WATER CONSTRUCTION. "SPECIAL CONSIDERATION SHALL BE GIVEN TO DEPTH OF COVER." (3) 434.18 LINE MARKERS. ADDED "API RP 1109 SHALL BE USED FOR GUIDANCE." (4) 450.2 OPERATION AND MAINTENANCE PLANS AND PROCEDURES. ADDED SUB-PARAGRAPHS (C), (D), (I), AND (K) COVERING OTHER SUGGESTIONS BY NTSB. (5) 451.3 MARKERS. ADDED "API RP 1109 SHALL BE USED FOR GUIDANCE." (6) 451.5 PATROLLING. ADDED A STATEMENT ESTABLISHING HOW OFTEN LIQUID PETROLEUM PIPELINES SHOULD BE PATROLLED. NOTE: PRIMARY PURPOSE OF PIPELINE PATROL IS TO LOOK FOR LEAKS OR CONSTRUCTION ACTIVITIES IN THE VACINITY OF THE PIPE LINE. (7) 454 EMERGENCY PLAN. ADDED A NEW PARAGRAPH TO THE B31.4 CODE COVERING WHAT SHOULD BE DONE IN THE EVENT OF SYSTEM FAILURES, ACCIDENTS, OR OTHER EMERGENCIES.

Addressee Acronym: ANSI

Addressee Organization Type: A-Associations

Communication Date: 1983-02-14

Communication Type: Official Correspondence

Addressee Acronym: ANSI

Addressee Organization Type: A-Associations

Communication Date: 1982-10-08

Communication Type: Official Correspondence

## Provenance

- Official: Yes
- Source: <https://data.ntsb.gov/carol-main-public/sr-details/P-73-025>
- Source ID: `ntsb-pipeline`
- SHA-256: `4c4fc75b1515806e39847b39f40492a17a5fc39f4d2b8442e2b77aa56e079167`
- Retrieved: 2026-08-20T04:57:24.741Z
- Exported: 2026-08-22T21:44:26.825Z
- Document slug: `ntsb-recommendation-p-73-025`

### Source metadata

```json
{
  "recordKind": "ntsb_safety_recommendation",
  "safetyRecommendationNumber": "P-73-025",
  "recommendationMode": "Pipeline",
  "topicMode": "Pipeline",
  "ntsbNumber": "80571",
  "priority": "CLASS II",
  "overallStatus": "Closed - Acceptable Action",
  "overallStatusAcronym": "CAA",
  "overallDateClosed": "1983-02-14",
  "lastModifiedDate": "2016-11-15",
  "reportNumber": "PSS-73-01",
  "reportUrl": "https://www.ntsb.gov/investigations/Pages/80571.aspx",
  "transmittalLetterUrl": "http://www.ntsb.gov/safety/safety-recs/recletters/P73_12_28.pdf",
  "addressees": [
    {
      "addresseeName": "American National Standards Institute",
      "addresseeStatusAcronym": "CNLA",
      "addresseeStatus": "Closed--No Longer Applicable",
      "addresseeDateClosed": "1983-02-14",
      "addresseeDetails": [
        {
          "addresseeAcronym": "ANSI",
          "addresseeOrganizationType": "A-Associations",
          "isFromNtsb": false,
          "communicationDate": "1982-12-20",
          "communicationType": "Official Correspondence",
          "communicationContents": "AMERICAN SOCIETY OF MECHANICAL ENGINEERS (ASME) LETTER: THIS WAS REFERRED BY ANSI TO ASME FOR RESPONSE SINCE ASME IS PUBLISHER OF B31.4 CODE.  THE FOLLOWING NEW ADDITIONS WERE MADE TO THE CODE TO INCORPORATE SOME OF THE SUGGESTIONS MADE BY NTSB:  (1) TABLE 434.6(A) MINIMUM COVER FOR BURIED PIPELINES.  (2) 434.14 OFFSHORE AND INLAND COASTAL WATER CONSTRUCTION.  \"SPECIAL CONSIDERATION SHALL BE GIVEN TO DEPTH OF COVER.\"  (3)  434.18 LINE MARKERS.  ADDED \"API RP 1109 SHALL BE USED FOR GUIDANCE.\"  (4)  450.2 OPERATION AND MAINTENANCE PLANS AND PROCEDURES.  ADDED SUB-PARAGRAPHS (C), (D), (I), AND (K) COVERING OTHER SUGGESTIONS BY NTSB.  (5) 451.3 MARKERS.  ADDED \"API RP 1109 SHALL BE USED FOR GUIDANCE.\"  (6)  451.5 PATROLLING.  ADDED A STATEMENT ESTABLISHING HOW OFTEN LIQUID PETROLEUM PIPELINES SHOULD BE PATROLLED.  NOTE: PRIMARY PURPOSE OF PIPELINE PATROL IS TO LOOK FOR LEAKS OR CONSTRUCTION ACTIVITIES IN THE VACINITY OF THE PIPE LINE.  (7)  454 EMERGENCY PLAN.  ADDED A NEW PARAGRAPH TO THE B31.4 CODE COVERING WHAT SHOULD BE DONE IN THE EVENT OF SYSTEM FAILURES, ACCIDENTS, OR OTHER EMERGENCIES."
        },
        {
          "addresseeAcronym": "ANSI",
          "addresseeOrganizationType": "A-Associations",
          "isFromNtsb": true,
          "communicationDate": "1983-02-14",
          "communicationType": "Official Correspondence",
          "communicationContents": ""
        },
        {
          "addresseeAcronym": "ANSI",
          "addresseeOrganizationType": "A-Associations",
          "isFromNtsb": true,
          "communicationDate": "1982-10-08",
          "communicationType": "Official Correspondence",
          "communicationContents": ""
        }
      ]
    }
  ],
  "jurisdiction": "US"
}
```