# NTSB Safety Recommendation P-98-003

**Citation:** P-98-003  
**Type / status:** guidance / guidance  
**Agency:** National Transportation Safety Board  
**Effective:** 1998-04-30  
**Published:** 1998-04-30

TO THE RESEARCH AND SPECIAL PROGRAMS ADMINISTRATION: Immediately notify those states & territories with gas pipeline safety programs of the susceptibility to premature brittle-like cracking of much of the plastic piping manufactured from the 1960s through the early 1980s & of the actions that the RSPA will require of gas system operators to monitor & replace piping that indicates unacceptable performance.

## Document text

NTSB safety recommendation P-98-003.

TO THE RESEARCH AND SPECIAL PROGRAMS ADMINISTRATION: Immediately notify those states & territories with gas pipeline safety programs of the susceptibility to premature brittle-like cracking of much of the plastic piping manufactured from the 1960s through the early 1980s & of the actions that the RSPA will require of gas system operators to monitor & replace piping that indicates unacceptable performance.

Priority: CLASS II

Overall Status: Closed - Acceptable Action

Issued Date: 1998-04-30

Adopted Date: 1998-04-23

Overall Date Closed: 2003-03-17

Synopsis: Despite the general acceptance of plastic piping as a safe and economical alternative to piping made of steel or other materials, the board notes that a number of pipeline accidents it has investigated have involved plastic piping that cracked in a brittle-like manner. For example, on 10/17/94, an explosion and fire in Waterloo, Iowa, destroyed a building and damaged other property. Six persons died and seven were injured in the accident. The board investigation determined that natural gas has been released from a plastic service pipe that had failed in a brittle-like manner at a connection to a steel main.

Probable Cause: None

Ntsbnumber: DCA95MP001

Report Number: SIR-98-01

Addressee Name: RSPA

Addressee Status: Closed - Acceptable Action

Addressee Date Closed: 2003-03-17

Addressee Acronym: RSPA

Addressee Organization Type: G-Federal Government

Communication Date: 1998-10-21

Communication Type: Official Correspondence

Communication Contents: THE BOARD WOULD APPRECIATE BEING ADVISED OF ANY ACTIONS THAT RSPA HAS TAKEN OR PLANS TO TAKE ON EACH OF THESE RECOMMENDATIONS. COPIES OF OUR 1/6/98, & OUR 4/30/98, CORRESPONDENCE ARE ENCLOSED.

Addressee Acronym: RSPA

Addressee Organization Type: G-Federal Government

Communication Date: 2000-07-13

Communication Type: Official Correspondence

Communication Contents: ON 11/15/99, BASED ON INFORMATION IN THE RSPA LETTER OF 3/17/99, P-98-1 THROUGH -5 WERE CLASSIFIED "OPEN--ACCEPTABLE RESPONSE," PENDING FURTHER REPLY FROM RSPA. COPIES OF RECOMMENDATIONS P-87-34, P-90-21, P-95-4, P-96-1, P-97-6, P-97-7, P-97-8, P-98-1, P-98-2, P-98-2, P-98-3, P-98-4, P-98-5, AND P-98-25 AND ASSOCIATED CORRESPONDENCE ARE ENCLOSED. THE SAFETY BOARD WOULD APPRECIATE LEARNING OF ANY ACTION TAKEN OR PLANNED TO COMPLY WITH THESE RECOMMENDATIONS, ESPECIALLY P-97-7 AND -8, WHICH MAY BE DISCUSSED AT A BOARD MEETING.

Addressee Acronym: RSPA

Addressee Organization Type: G-Federal Government

Communication Date: 2003-03-17

Communication Type: Official Correspondence

Communication Contents: In response to Safety Recommendations P-98-1 and -3, RSPA issued three Advisory Bulletins (ABs), two in March 1999, and one in 2002, stating the problems with brittle-like cracking of older plastic pipe. The two 1999 ABs highlight the need for gas system operators to monitor and replace piping that indicates unacceptable performance, and the 2002 AB recommends that all owners and operators of natural gas distribution systems identify all plastic pipe installed in the 1980s. Although RSPA has not required operators to develop plans to monitor and replace piping that indicates poor performance, it conducted several surveys of the states concerning oversight of operators that used polyethylene pipe manufactured by Century Utility Products, Inc. and their replacement efforts. RSPA's review of accidents nationwide revealed that only six states identified operators using the pipe in their systems. As of October 31, 2002, RSPA's Office of Pipeline Safety, Central Region Office, reported that operators in the six states have been aggressive in replacing this pipe and that they have developed plans and programs to ensure the safe operation of pipelines. As these actions are fully responsive to the intent of the Board's recommendations, Safety Recommendations P-98-1 and -3 are classified "Closed--Acceptable Action."

Addressee Acronym: RSPA

Addressee Organization Type: G-Federal Government

Communication Date: 1999-11-15

Communication Type: Official Correspondence

Communication Contents: THE BOARD UNDERSTANDS THAT RSPA, IN MARCH 1999, ISSUED AN ADVISORY ON THE POTENTIAL FOR BRITTLE-LIKE CRACKING OF OLDER PLASTIC PIPING TO THE GAS DISTRIBUTION PIPELINE INDUSTRY AND THE STATE PIPELINE SAFETY PROGRAM OFFICES. HOWEVER, THE BOARD ASKED THAT RSPA "REQUIRE," NOT "RECOMMEND," THAT GAS SYSTEM OPERATORS MONITOR AND REPLACE PIPING THAT INDICATES UNACCEPTABLE PERFORMANCE. ACCORDINGLY, PENDING FURTHER INFORMATION FROM RSPA ON WHETHER IT WILL REQUIRE THE RECOMMENDED ACTION, P-98-3 HAS BEEN CLASSIFIED "OPEN--ACCEPTABLE RESPONSE."

Addressee Acronym: RSPA

Addressee Organization Type: G-Federal Government

Communication Date: 2002-12-11

Communication Type: Official Correspondence

Communication Contents: Letter Mail Controlled 12/18/2002 3:01:52 PM MC# 2021044 In Safety Recommendations P-98-1 and P-98-3, NTSB asked that RSPA notify pipeline operators, States and territories of the susceptibility to premature cracking of pipe manufactured between the 1960s and the 1980s and, in particular, of the susceptibility of pipe extruded by Century Utility Products, Inc. In addition, NTSB recommended that RSPA require operators to develop plans to monitor the performance of the piping in question and to identify and replace any piping that indicated poor performance. In response to these two recommendations, RSPA issued two Advisory Bulletins in March 1999 to warn owners and operators of natural gas distribution systems of the susceptibility to premature brittle-like cracking of much of the plastic pipe manufactured from the 1960s through the early 1980s. A third Advisory Bulletin was published on November 26, 2002 (67 FR 70806). The Advisory Bulletin reiterates the problems with brittle-like cracking of older plastic pipe and highlights the need for gas system operators to monitor and replace piping that indicates unacceptable performance. This new advisory recommends that all owners and operators of natural gas distribution systems identify all plastic pipe installed in the 1980s. RSPA distributes all Advisory Bulletins and regulatory updates to all States and territories with gas pipeline safety programs as part of its monthly State mailing. This information is also posted on the OPS web site at www.ops.dot.gov. RSPA believes the Advisory Bulletin process is the best method to inform operators of safety issues requiring immediate action. Although RSPA has not specifically required operators to develop plans to monitor and replace piping that indicates poor performance, RSPA has conducted several surveys of the States concerning oversight of the operators with known Century Pipe and of their replacement efforts. Since 1997, RSPA has sought information on gas distribution systems using polyethylene pipe manufactured by Century Utility Products, Inc. In a letter to NTSB's Rod Dyck on January 16, 1997, RSPA reported that following a review of accidents nationwide, only six States identified operators using Century pipe in their systems. The other States have no known Century pipe. On October 3 1, 2002, the Office of Pipeline Safety's Central region office reported that the operators have been aggressive in replacing Century pipe and that they have developed plans and programs to ensure the safe operation of pipelines. The status of replacement pipe in the Central region States follows: · Iowa - All known Century pipe was replaced in 2001. · Illinois - Of the 74,000 feet of Century pipe identified, 18,500 feet have been replaced and the final 55,500 feet are scheduled for replacement by April 30,2003. · In Michigan - one operator with approximately 740,000 feet of Century pipe in service has replaced 45,000 feet in the last four years and overall 140,000 feet in the last 16 years. A study by this operator indicates that third-party damage caused more leaks to the Century pipe than the inherent characteristics of the pipe. · Minnesota - approximately 100,000 feet of service lines and 95,000 feet of main have been replaced in the last four years. Approximately 190,000 feet of service lines and 640,000 feet of main are left to be replaced. · North Dakota - All known Century pipe has been replaced. The operator was required to have a replacement program by the State. · South Dakota - 42,000 feet has been replaced in the last four years with approximately 38,000 feet of Century pipe remaining in service. The operator is conducting leak detection surveys four times per year until all the pipe is replaced. RSPA believes that the three Advisory Bulletins and the progress made by the operators to replace the identified pipe fully meets the intent of P-98-l and P-98-3. Based on the information provided above, RSPA requests that NTSB Safety Recommendation P-98-3 be reclassified as "CLOSED-Acceptable Action."

Addressee Acronym: RSPA

Addressee Organization Type: G-Federal Government

Communication Date: 1999-03-17

Communication Type: Official Correspondence

Communication Contents: Letter Mail Controlled 9/17/1999 3:30:10 PM MC# 990813 WE AGREE WITH THE FINDINGS OF NTSB SPECIAL INVESTIGATION REPORT (NTSB/SIR-98/01) THAT CERTAIN PLASTIC PIPE USED IN NATURAL GAS DISTRIBUTION SERVICE MAY BE SUSCEPTIBLE TO BRITTLE-LIKE CRACKING. THE STANDARDS USED TO RATE THE LONG-TERM OF PLASTIC PIPE MAY HAVE OVERRATED THE STRENGTH AD RESISTANCE TO BRITTLE-LIKE CRACKING OF MUCH OF THE PLASTIC PIPE MANUFACTURED AND USED FOR GAS SERVICE FOR GAS IN THE 1960'S THROUGH THE EARLY 1990'S. RSPA ADDRESSED THIS RECOMMENDATION BY ISSUING AN ADVISORY BULLETIN IN MARCH 1999 ON THE POTENTIAL FOR BRITTLE-LIKE CRACKING OF OLDER PLASTIC PIPING TO THE GAS DISTRIBUTION PIPELINE INDUSTRY AND THE STATE PIPELINE SAFETY PROGRAM OFFICES. THE ADVISORY BULLETIN RECOMMENDED ALL OWNERS AND OPERATORS OF NATURAL GAS DISTRIBUTION SYSTEMS IDENTIFY ALL PRE-1982 PLASTIC PIPE INSTALLATIONS ANALYZE LEAK HISTORIES, AND EVALUATE ANY CONDITIONS THAT MAY IMPOSE HIGH STRESSES ON THE PIPE. THE OPERATORS SHOULD TAKE APPROPRIATE MEDIAL ACTION, INCLUDING REPLACEMENT, TO MITIGATE ANY RISKS TO PUBLIC SAFETY. RSPA REQUESTS THAT P-98-3 BE CLASSIFIED "CLOSED--ACCEPTABLE ACTION."

## Provenance

- Official: Yes
- Source: <https://data.ntsb.gov/carol-main-public/sr-details/P-98-003>
- Source ID: `ntsb-pipeline`
- SHA-256: `cc1be7e1c86bf60ded836e6ba770aaf54f6f99cdb6f10a466845ccd701354091`
- Retrieved: 2026-08-20T04:57:24.741Z
- Exported: 2026-08-22T23:53:18.702Z
- Document slug: `ntsb-recommendation-p-98-003`

### Source metadata

```json
{
  "recordKind": "ntsb_safety_recommendation",
  "safetyRecommendationNumber": "P-98-003",
  "recommendationMode": "Pipeline",
  "topicMode": "Pipeline",
  "ntsbNumber": "DCA95MP001",
  "priority": "CLASS II",
  "overallStatus": "Closed - Acceptable Action",
  "overallStatusAcronym": "CAA",
  "overallDateClosed": "2003-03-17",
  "lastModifiedDate": "2016-11-15",
  "reportNumber": "SIR-98-01",
  "reportUrl": "https://www.ntsb.gov/investigations/Pages/DCA95MP001.aspx",
  "transmittalLetterUrl": "http://www.ntsb.gov/safety/safety-recs/recletters/P98_1_5.pdf",
  "addressees": [
    {
      "addresseeName": "RSPA",
      "addresseeStatusAcronym": "CAA",
      "addresseeStatus": "Closed - Acceptable Action",
      "addresseeDateClosed": "2003-03-17",
      "addresseeDetails": [
        {
          "addresseeAcronym": "RSPA",
          "addresseeOrganizationType": "G-Federal Government",
          "isFromNtsb": true,
          "communicationDate": "1998-10-21",
          "communicationType": "Official Correspondence",
          "communicationContents": "THE BOARD WOULD APPRECIATE BEING ADVISED OF ANY ACTIONS THAT RSPA HAS TAKEN OR PLANS TO TAKE ON EACH OF THESE RECOMMENDATIONS.  COPIES OF OUR 1/6/98, & OUR 4/30/98, CORRESPONDENCE ARE ENCLOSED."
        },
        {
          "addresseeAcronym": "RSPA",
          "addresseeOrganizationType": "G-Federal Government",
          "isFromNtsb": true,
          "communicationDate": "2000-07-13",
          "communicationType": "Official Correspondence",
          "communicationContents": "ON 11/15/99, BASED ON INFORMATION IN THE RSPA LETTER OF 3/17/99, P-98-1 THROUGH -5 WERE CLASSIFIED \"OPEN--ACCEPTABLE RESPONSE,\" PENDING FURTHER REPLY FROM RSPA.  COPIES OF RECOMMENDATIONS P-87-34, P-90-21, P-95-4, P-96-1, P-97-6, P-97-7, P-97-8, P-98-1, P-98-2, P-98-2, P-98-3, P-98-4, P-98-5, AND P-98-25 AND ASSOCIATED CORRESPONDENCE ARE ENCLOSED.  THE SAFETY BOARD WOULD APPRECIATE LEARNING OF ANY ACTION TAKEN OR PLANNED TO COMPLY WITH THESE RECOMMENDATIONS, ESPECIALLY P-97-7 AND -8, WHICH MAY BE DISCUSSED AT A BOARD MEETING."
        },
        {
          "addresseeAcronym": "RSPA",
          "addresseeOrganizationType": "G-Federal Government",
          "isFromNtsb": true,
          "communicationDate": "2003-03-17",
          "communicationType": "Official Correspondence",
          "communicationContents": "In response to Safety Recommendations P-98-1 and -3, RSPA issued three Advisory Bulletins (ABs), two in March 1999, and one in 2002, stating the problems with brittle-like cracking of older plastic pipe.  The two 1999 ABs highlight the need for gas system operators to monitor and replace piping that indicates unacceptable performance, and the 2002 AB recommends that all owners and operators of natural gas distribution systems identify all plastic pipe installed in the 1980s.\r\n\r\nAlthough RSPA has not required operators to develop plans to monitor and replace piping that indicates poor performance, it conducted several surveys of the states concerning oversight of operators that used polyethylene pipe manufactured by Century Utility Products, Inc. and their replacement efforts.  RSPA's review of accidents nationwide revealed that only six states identified operators using the pipe in their systems.  As of October 31, 2002, RSPA's Office of Pipeline Safety, Central Region Office, reported that operators in the six states have been aggressive in replacing this pipe and that they have developed plans and programs to ensure the safe operation of pipelines.  As these actions are fully responsive to the intent of the Board's recommendations, Safety Recommendations P-98-1 and -3 are classified \"Closed--Acceptable Action.\""
        },
        {
          "addresseeAcronym": "RSPA",
          "addresseeOrganizationType": "G-Federal Government",
          "isFromNtsb": true,
          "communicationDate": "1999-11-15",
          "communicationType": "Official Correspondence",
          "communicationContents": "THE BOARD UNDERSTANDS THAT RSPA, IN MARCH 1999, ISSUED AN ADVISORY ON THE POTENTIAL FOR BRITTLE-LIKE CRACKING OF OLDER PLASTIC PIPING TO THE GAS DISTRIBUTION PIPELINE INDUSTRY AND THE STATE PIPELINE SAFETY PROGRAM OFFICES.  HOWEVER, THE BOARD ASKED THAT RSPA \"REQUIRE,\" NOT \"RECOMMEND,\" THAT GAS SYSTEM OPERATORS MONITOR AND REPLACE PIPING THAT INDICATES UNACCEPTABLE PERFORMANCE.  ACCORDINGLY, PENDING FURTHER INFORMATION FROM RSPA ON WHETHER IT WILL REQUIRE THE RECOMMENDED ACTION, P-98-3 HAS BEEN CLASSIFIED \"OPEN--ACCEPTABLE RESPONSE.\""
        },
        {
          "addresseeAcronym": "RSPA",
          "addresseeOrganizationType": "G-Federal Government",
          "isFromNtsb": false,
          "communicationDate": "2002-12-11",
          "communicationType": "Official Correspondence",
          "communicationContents": "Letter Mail Controlled 12/18/2002 3:01:52 PM MC# 2021044      In Safety Recommendations P-98-1 and P-98-3, NTSB asked that RSPA notify pipeline operators, States and territories of the susceptibility to premature cracking of pipe manufactured between the 1960s and the 1980s and, in particular, of the susceptibility of pipe extruded by Century Utility Products, Inc. In addition, NTSB recommended that RSPA require operators to develop plans to monitor the performance of the piping in question and to identify and replace any piping that indicated poor performance.  In response to these two recommendations, RSPA issued two Advisory Bulletins in March 1999 to warn owners and operators of natural gas distribution systems of the susceptibility to premature brittle-like cracking of much of the plastic pipe manufactured from the 1960s through the early 1980s. A third Advisory Bulletin was published on November 26, 2002 (67 FR 70806). The Advisory Bulletin reiterates the problems with brittle-like cracking of older plastic pipe and highlights the need for gas system operators to monitor and replace piping that indicates unacceptable performance. This new advisory recommends that all owners and operators of natural gas distribution systems identify all plastic pipe installed in the 1980s. RSPA distributes all Advisory Bulletins and regulatory updates to all States and territories with gas pipeline safety programs as part of its monthly State mailing. This information is also posted on the OPS web site at www.ops.dot.gov. RSPA believes the Advisory Bulletin process is the best method to inform operators of safety issues requiring immediate action.\r\nAlthough RSPA has not specifically required operators to develop plans to monitor and replace piping that indicates poor performance, RSPA has conducted several surveys of the States concerning oversight of the operators with known Century Pipe and of their replacement efforts. Since 1997, RSPA has sought information on gas distribution systems using polyethylene pipe manufactured by Century Utility Products, Inc. In a letter to NTSB's Rod Dyck on January 16, 1997, RSPA reported that following\r\na review of accidents nationwide, only six States identified operators using Century pipe in their systems. The other States have no known Century pipe. On October 3 1, 2002, the Office of Pipeline Safety's Central region office reported that the operators have been aggressive in replacing Century pipe and that they have developed plans and programs to ensure the safe operation of pipelines. The status of replacement pipe in the Central region States follows:\r\n\r\n· Iowa - All known Century pipe was replaced in 2001.\r\n· Illinois - Of the 74,000 feet of Century pipe identified, 18,500 feet have been replaced and the final 55,500 feet are scheduled for replacement by April 30,2003.\r\n· In Michigan - one operator with approximately 740,000 feet of Century pipe in service has replaced 45,000 feet in the last four years and overall 140,000 feet in the last 16 years. A study by this operator indicates that third-party damage caused more leaks to the Century pipe than the inherent characteristics of the pipe.\r\n· Minnesota - approximately 100,000 feet of service lines and 95,000 feet of main have been replaced in the last four years. Approximately 190,000 feet of service lines and 640,000 feet of main are left to be replaced.\r\n· North Dakota - All known Century pipe has been replaced. The operator was required to have a replacement program by the State.\r\n· South Dakota - 42,000 feet has been replaced in the last four years with approximately 38,000 feet of Century pipe remaining in service. The operator is conducting leak detection surveys four times per year until all the pipe is replaced.\r\n\r\nRSPA believes that the three Advisory Bulletins and the progress made by the operators to replace the identified pipe fully meets the intent of P-98-l and P-98-3.  Based on the information provided above, RSPA requests that NTSB Safety Recommendation P-98-3 be reclassified as \"CLOSED-Acceptable Action.\""
        },
        {
          "addresseeAcronym": "RSPA",
          "addresseeOrganizationType": "G-Federal Government",
          "isFromNtsb": false,
          "communicationDate": "1999-03-17",
          "communicationType": "Official Correspondence",
          "communicationContents": "Letter Mail Controlled 9/17/1999 3:30:10 PM MC# 990813     WE AGREE WITH THE FINDINGS OF NTSB SPECIAL INVESTIGATION REPORT (NTSB/SIR-98/01) THAT CERTAIN PLASTIC PIPE USED IN NATURAL GAS DISTRIBUTION SERVICE MAY BE SUSCEPTIBLE TO BRITTLE-LIKE CRACKING.  THE STANDARDS USED TO RATE THE LONG-TERM OF PLASTIC PIPE MAY HAVE OVERRATED THE STRENGTH AD RESISTANCE TO BRITTLE-LIKE CRACKING OF MUCH OF THE PLASTIC PIPE MANUFACTURED AND USED FOR GAS SERVICE FOR GAS IN THE 1960'S THROUGH THE EARLY 1990'S.  RSPA ADDRESSED THIS RECOMMENDATION BY ISSUING AN ADVISORY BULLETIN IN MARCH 1999 ON THE POTENTIAL FOR BRITTLE-LIKE CRACKING OF OLDER PLASTIC PIPING TO THE GAS DISTRIBUTION PIPELINE INDUSTRY AND THE STATE PIPELINE SAFETY PROGRAM OFFICES.  THE ADVISORY BULLETIN RECOMMENDED ALL OWNERS AND OPERATORS OF NATURAL GAS DISTRIBUTION SYSTEMS IDENTIFY ALL PRE-1982 PLASTIC PIPE INSTALLATIONS ANALYZE LEAK HISTORIES, AND EVALUATE ANY CONDITIONS THAT MAY IMPOSE HIGH STRESSES ON THE PIPE.  THE OPERATORS SHOULD TAKE APPROPRIATE MEDIAL ACTION, INCLUDING REPLACEMENT, TO MITIGATE ANY RISKS TO PUBLIC SAFETY.  RSPA REQUESTS THAT P-98-3 BE CLASSIFIED \"CLOSED--ACCEPTABLE ACTION.\""
        }
      ]
    }
  ],
  "jurisdiction": "US"
}
```