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Safety Recommendation Details

Safety Recommendation R-84-015
Details
Synopsis: ON JULY 30, 1983, VINYL CHLORIDE UNDER PRESSURE ESCAPED FROM A NEWLY LOADED BUT NOT YET SECURED RAILROAD TANK CAR AT THE LOADING FACILITY WITHIN FORMOSA PLASTIC CORPORATION'S (FORMOSA) PLANT AT BATON ROUGE, LOUISIANA. THE TANK CAR WAS A U.S. DEPARTMENT OF TRANSPORTATION (DOT) SPECIFICATION 105 A 300 W TANK CAR, UTLX 96402, BUILT BY THE UNION TANK CAR (UTC) COMPANY. SOON THEREAFTER, THE RELEASED VINYL CHLORIDE WAS IGNITED AND FORMED A LARGE BILLOWING FIRE. AN ADJACENT TANK CAR CONTAINING VINYL CHLORIDE BECAME DIRECTLY INVOLVED IN THE FIRE. TANK CAR UTLX 96402 LOST ITS CONTENTS THROUGH ITS LOADING PIPING AT THE TOP OF THE TANK AND WAS DESTROYED BY FIRE FUELED BY THE POOL OF THE ESCAPING VINYL CHLORIDE WHICH FORMED BENEATH IT; THE TORCH-LIKE FIRE THAT EMANATED FROM THE TANK CAR UTLX 96402 IMPINGED UPON THE ADJACENT TANK CAR CAUSING ITS SHELL TO THIN, BULGE, AND RUPTURE NON VIOLENTLY. AS A RESULT OF THIS ACCIDENT, TWO PESONS WERE INJURED AND THE SAFETY OF THE ADJACENT COMMUNITY WAS ENDANGERED. HAD THE SECOND TANK CAR RUPTURED VIOLENTLY, A POTENTIAL FOR CATASTROPHIC LOSSES EXISTED BECAUSE OF THE THREAT POSED TO THE VINYL CHLORIDE MANUFACTURING PLANT, VINYL CHLORIDE STORAGE SPHERES, CHLORINE STORAGE TANKS, NUMEROUS TANK CARS, AND OTHER PLANT FACILITIES.
Recommendation: THE NTSB RECOMMENDS THAT THE FEDERAL RAILROAD ADMINISTRATION: IMMEDIATELY INITIATE INSPECTIONS OF TANK CARS EQUIPPED WITH EXCESS FLOW VALVES TO DETERMINE THE EXTENT TO WHICH THESE TANK CARS MAY HAVE IMPROPERLY POSITIONED EXCESS FLOW VALVE SEATS, DETERMINE THE CAUSE OF DEFICIENT CONDITIONS FOUND, AND REQUIRE CORRECTION OF DEFICIENCIES BEFORE INSPECTED TANK CARS ARE RETURNED TO SERVICE. (URGENT)
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Action
Mode: Railroad
Location: Baton Rouge, LA, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA83AZ006
Accident Reports: Vinyl Chloride Monomer Release from a Railroad Tank Car and Fire, Formosa Plastics Corporation Plant
Report #: RAR-85-08
Accident Date: 7/30/1983
Issue Date: 3/15/1984
Date Closed: 3/29/1990
Addressee(s) and Addressee Status: FRA (Closed - Acceptable Action)
Keyword(s): Hazmat,Tank Car Loading and Unloading

Safety Recommendation History
From: NTSB
To: FRA
Date: 3/29/1990
Response: Based both on the actions taken by the Association of American Railroads to bring about an intensive inspection of tank cars equipped with excess flow valves and to modify its tank car specifications to reduce the likelihood of a similar accident, and on the FRA/RSPA final rule which makes the inspection a required action, Safety Recommendation R-84-15 has been classified as "Closed-Acceptable Action."

From: FRA
To: NTSB
Date: 10/20/1989
Response: The Research and Special programs Administration (RSPA) has published Docket HM-166W, Miscellaneous Amendments in the Federal Register (copy enclosed) September 20, 1989. This Final Rule requires the inspection of all excess flow valves having threaded seats, including those not capable of loosening in transit and those designed with positive locking devices. Inspections are required at the time of each retest and safety valve retest interval. Since these actions are responsive to recommendation R-84-15, it should be placed in an "closed-acceptable action" status.

From: NTSB
To: FRA
Date: 5/23/1989
Response: Although the FRA has not implemented the actions recommended, the Safety Board is pleased to note that the FRA along with the Research and Special Programs Administration has published a Notice of Proposed Rulemaking to revise the hazardous materials regulations. The proposal, if implemented, would require excess flow valves to have threaded seats to be checked for tightness and tightened at the time of each tank retest or safety relief valve retest. We will continue to hold this recommendation in an "Open-Acceptable Action" status pending the completion of this regulatory initiative. Inasmuch as a final rule was expected to be published in March 1989, but to date has not been published, we would appreciate receiving a periodic update on the status of this rulemaking effort as it progresses.

From: FRA
To: NTSB
Date: 3/17/1989
Response: THE FRA WAS ADVISED, BY THE ASSOCIATION OF AMERICAN RAILROADS (AAR), THAT AS OF SEPTEMBER 17, 1986, A TOTAL OF 5,176 CARS (15,528 EXCESS FLOW VALVES), APPROXIMATELY 31 PERCENT OF ALL CARS INVOLVED, HAD BEEN INSPECTED. OF THESE, 853 CARS (16 PERCENT) HAD ONE OR MORE LOOSE SEATS, AND 26 VALVE SEATS WERE FOUND TO BE DISENGAGED (AAR LETTER ENCLOSED). SINCE THAT DATE, APPROX. 95 PERCENT OF THE TANK CARS REQUIRED TO HAVE EXCESS FLOW VALVES HAVE BEEN INSPECTED. THE REMAINING 5 PERCENT OF THE TANK CARS ARE REQUIRED TO BE INSPECTED THIS YEAR. INSPECTION RESULTS SHOWED A NEED FOR REGULAR ASSESSMENT OF THE INTEGRITY OF THE EXCESS FLOW VALVE SEATS. EFFECTIVE NOVEMBER 10, 1988, THE AAR TANK CAR COMMITTEE (TCC) APPROVED WORDING FOR SECTION D4.06 OF M-1002, SPECIFICATIONS FOR TANK CARS AS FOLLOWS: "ANY TANK CAR EQUIPPED WITH EXCESS FLOW VALVES (EFV) HAVING THREADED SEATS CAPABLE OF LOOSENING IN TRANSIT MUST BE CHECKED FOR TIGHTNESS AT THE TIME A PRESSURE RELIEF VALVE RETEST IS SPECIFIED OR AT ANY TIME A VALVE OVER SUCH SEAT IS REMOVED FOR ANY REASON. THE MAXIMUM TIGHTNESS INTERVAL IS 5 YEARS. THREADED SEATS ARE TO BE CONSIDERED CAPABLE OF LOOSENING UNLESS POSITIVE LOCKING DEVICES ARE PROVIDED OR THE SEAT IS CONFINED DUE TO DESIGN FEATURES. SEATS MUST BE TIGHTENED WITH A 24" WRENCH, MINIMUM." THE TCC HAS ALSO AUTHORIZED THE CERTIFICATE OF TEST FORM (D1) TO BE MODIFIED TO INCLUDE AN ENTRY FOR THE EXCESS FLOW VALVE TIGHTNESS CERTIFICATION. IN ADDITION, THE FRA ALONG WITH THE RESEARCH AND SPECIAL ADMINISTRATION PUBLISHED A NOTICE OF PROPOSED RULEMAKING (NPRM) THAT WILL RQUIRE EXCESS FLOW VALVES HAVING THREADED SEATS TO BE CHECKED FOR TIGHTNESS AND TIGHTENED AT THE TIME OF EACH TANK RETEST OR SAFETY RELIEF VALVE RETEST. THE NPRM PROPOSES A MORE STRINGENT REQUIREMENT THAN THAT IMPOSED BY THE AAR. OUR REQUIREMENT CALLS FOR THE INSPECTION OF ALL EXCESS FLOW VALVES HAVING THREADED SEATS, INCLUDING THOSE NOT CAPABLE OF LOOSENING IN TRANSIT AND THOSE DESIGNED WITH POSITIVE LOCKING DEVICES. THE FINAL RULE IS EXPECTED TO BE PUBLISHED MARCH 1989. FRA BELIEVES THE ACTION TAKEN, AS NOTED IN THIS LETTER, HAVE SATISFIED THE BOARD'S RECOMMENDATION AND WE REQUEST THAT IT BE PLACED IN A "CLOSED--ACCEPTABLE ACTION" STATUS.

From: NTSB
To: FRA
Date: 8/19/1987
Response: The Safety Board notes the Federal Railroad Administration's (FRA) statement that the Association of American Railroads' (AAR) excess flow valve inspection program is not satisfactory for chlorine tank cars. We note further that in spite of FRA's acceptance of AAR's position that the chlorine excess flow valve has a unique design, FRA is recommending to the Research and Special Programs Administration (RSPA) that the hazardous materials regulations be revised to require the inspection of excess flow valves whenever a tank or safety release valve must be retested. While the AAR contends that this currently is industry practice, the revision to the regulations would assure this inspection. The Board would appreciate being kept informed of RSPA's efforts to revise the regulations. In the meantime, Safety Recommendation R-84-15 will remain in an "Open-Acceptable Action" status. The Board would also appreciate being kept apprised of AAR's service trials of two new spring loaded ball check valve designs.

From: FRA
To: NTSB
Date: 6/26/1987
Response: THE THREE (3) LETTERS THAT FRA RECEIVED FROM THE ASSOCIATION OF AMERICAN RAILROADS CONCERNING THE INSPECTION OF EXCESS FLOW VALVES. THE AAR HAS EXPANDED THEIR EXCESS FLOW VALVE INSPECTION PROGRAM TO INCLUDE ETHYLENE OXIDE TANK CARS. HOWEVER, THEY HAVE DECLINED TO EXPAND THEIR INSPECTION PRO GRAM TO INCLUDE CHLORINE TANK CARS BECAUSE OF THEIR BELIEF THAT THE UNIQUE DESIGN OF EXCESS FLOW VALVES FOR CHLORINE TANK CARS MAKES THE POSSIBILITY OF THE COMPLETE DISENGAGE MENT OF THOSE VALVES UNLIKELY. THE AAR ALSO NOTES THAT TANKS AND SAFETY RELIEF VALVES IN CHLORINE SERVICE MUST BE RETESTED EVERY TWO YEARS AND THAT THE EXCESS FLOW VALVES ARE USUALLY INSPECTED WHEN THE TANKS AND SAFETY RELIEF VALVES IN CHLORINE SERVICE MUST BE RETESTED EVERY TWO YEARS AND THE EXCESS FLOW VALVES ARE USUALLY INSPECTED WHEN THE TANKS AND SAFETY RELIEF VALVES ARE TESTED. THE FRA BELIEVES THAT THE AAR EXCESS FLOW VALVE INSPECTION PROGRAM SATISFIES THE IN TENTION OF RECOMMENDATION R-84-15 FOR FLAMMABLE GAS AND ETHYLENE OXIDE TANK CARS. THE AAR PROGRAM IS NOT SATISFAC TORY FOR CHLORINE TANK CARS. WE DO NOT DISPUTE THE AAR'S ARGUMENTS CONCERNING THE UNIQUE DESIGN OF CHLORINE EXCESS FLOW VALVES. HOWEVER, PARTIALLY DISENGAGED EXCESS FLOW VALVES ARE NOT ACCEPTABLE IN CHLORINE SERVICE. WE HAVE RECOMMENDED TO THE RESEARCH AND SPECIAL PROGRAMS ADMINISTRA TION THAT PARAGRAPH 173.31 (C) OF THE HAZARDOUS MATERIALS REGULATIONS BE REVISED TO REQUIRE THE INSPECTION OF EXCESS FLOW VALVES WHENEVER A TANK CAR SAFETY RELIEF VALVE MUST BE RETESTED. CONCERNING THE ISSUE OF NEW EXCESS FLOW VALVE DESIGNS, THE AAR TANK CAR COMMITTEE IS CONSIDERING SERVICE TRIALS OF TWO NEW SPRING LOADED BALL CHECK VALVE DESIGNS. CONCERNING THE ISSUE OF THE REINSPECTION OF EXCESS FLOW VALVES, THE AAR TANK CAR COMMITTEE HAS ALREADY REINSPECTED A REPRESENTATIVE SAMPLE OF EXCESS FLOW VALVES. IT WAS THESE REINSPECTIONS THAT INDICATED A NEED FOR THE USE OF A 24-INCH WRENCH FOR TIGHTENING. SINCE FRA HAS TAKEN POSITIVE ACTION TO PREVENT A RECURRENCE OF THE FORMOSA ACCIDENT, RECOMMENDA TION R-84-15 SHOULD BE CLOSED.

From: NTSB
To: FRA
Date: 10/27/1986
Response: The Safety Board is pleased to not that the federal railroad Administration (FRA) agrees with the Board's position that the excess flow valve inspection program should be broadened to include all tank cars required to have excess flow valves and not be limited to flammable gas tank cars. While the Board notes that the FRA will recommend such action to the Association of American Railroads (AAR) and we look forward to receiving a response, the Board points out that any action short of inspecting all tank cars required to have excess flow valves will not be considered responsive to the full intent of the Board's recommendation. The Board notes further that the AAR final circular letter did indicate in what manner excess flow valves are to be tightened. While we appreciate clarification of this matter, we point out that the other concerns outlined in our January 14, 1986, letter have yet to be addressed. We do note, however, that the FRA has questioned the AAR on a number of issues in its May 7, 1986, letter, including the reinspection program and the Tank Car Committee's consideration of a positive locking device to replace the removable valve seat. With respect to the reinspection program, the Board remains concerned that the reinspection conceivably would not take place for as long as 5 years if the cars are not to be reinspected until the next tank or safety valve retest or the next time the car is cleaned. The Safety Board would appreciate being informed of AAR's response to FRA's May 7, 1986, letter and of any action contemplated by FRA if AAR's response is found to be inadequate. In the meantime, Safety Recommendation R-84-15 will remain in an "Open-Acceptable Action" status.

From: FRA
To: NTSB
Date: 8/11/1986
Response: I APPRECIATE YOUR RECENT LETTER REQUESTING THAT THE FRA PROVIDE THE NTSB WITH ADDITIONAL INFORMATION CONCERNING THE IMPLEMENTATION OF RECOMMENDATION R-84-15. THE NTSB NOTED THAT THE EXCESS FLOW VALVE INSPECTION PROGRAM OF THE AAR ONLY ADDRESSES FLAMMABLE GAS TANK CARS AND SUGGESTED THAT THE INSPECTION PROGRAM BE BROADENED TO ALL TANK CARS REQUIRED TO HAVE EXCESS FLOW VALVES. FRA AGREES WITH THAT POSITION AND WILL RECOMMEND TO THE AAR THAT THEIR INSPEC TION PROGRAM BE BROADENED. NTSB ALSO NOTED THAT AAR'S DRAFT CIRCULAR LETTER WOULD NOT SPECIFY HOW THE EXCESS FLOW VALVES ARE TO BE TIGHTENED. HOWEVER, THE FINAL CIRCULAR LETTER DOES INCLUDE A DRAWING OF THE PLUG WRENCH THAT SHOULD BE USED TO TIGHTEN EXCES FLOW VALVES. NTSB ALSO REQUESTED IN FORMATION ON THE STATUS OF AAR'S REINSPECTION PROGRAM AND OF THE AAR TANK CAR COMMITTEE'S REVIEW OF THE FEASIBILITY OF ELIMINATING SEPARABLE VALVE SEATS OR PROVIDING A POSITIVE LOCKING DEVICE. ENCLOSED IS A LETTER THAT WAS SENT BY FRA TO AAR REQUESTING THAT INFORMATION. WE WILL PROVIDE YOU WITH A COPY OF AAR'S RESPONSE. SINCE FRA HAS TAKEN POSITIVE ACTION TO PREVENT A RECURRENCE OF THE FORMOSA ACCIDENT, RECOMMENDATION R-84-15 SHOULD BE CLOSED.

From: NTSB
To: FRA
Date: 1/14/1986
Response: The Safety Board appreciates being informed of the results of the initial inspection program conducted by the Association of American Railroads' (AAR) Tank Car Committee task force and of the measure adopted by the AAR Tank Car Committee at its March 1985 meeting to address the problem of loose excess flow valves. The Safety Board is concerned, however, that particular aspects of the measures adopted by the Tank Car Committee may not be sufficiently specific. The Board notes that the circular letter to be issued to the AAR members and to the private tank car owners addresses excess flow valves only on tank cars used to transport a flammable gas. The Board questions the rationale for limiting the inspection to these tank cars. We believe that all tank cars that are required to have excess flow valves should be included without regard to the commodity being transported and that the circular letter issued to the AAR members should reflect this. The Board notes further that the circular letter is to indicate that the excess flow valves are to "be checked for tightness and tightened…;" however, the letter does not indicate to what specification or in what manner the excess flow valves are to be tightened. As outlined in the FRA's letter, the third measure adopted by the AAR Tank Car Committee is that a representative sample of the tank cars addressed in the circular letter to be issued to the AAR members are to be reinspected. The Board's concern is that there is no indication as to when this reinspection will occur. If the cars are not to be reinspected until the next tank or safety valve retest or the next time the car is cleaned, as outlined in the proposed circular letter, the reinspection conceivably would not take place for as long as 5 years. The Board would appreciate clarification of this matter. The Board noted further that the AAR Tank Car Committee is to review excess flow valve design to consider eliminating separable valve seats in the 2-inch and 3-inch sizes, or to provide a positive locking device. The Board would appreciate being informed of the outcome of this review. In view of the FRA's efforts to date to address this safety problem, Safety Recommendation R-84-15 will remain in its current status of "Open-Acceptable Action," pending further response to the Board's concerns.

From: FRA
To: NTSB
Date: 8/27/1985
Response: THE FRA AND THE AAR HAVE IMPLEMENTED A PROGRAM TO INSPECT AND CORRECT A LOOSENING PROBLEM ON THE EXCESS FLOW VALVES USED ON CERTAIN TANK CARS. FOLLOWING A 1983 INCIDENT WHERE VINYL CHLORIDE ESCAPED FROM A TANK CAR DURING LOADING, THE NTSB RECOMMENDED THAT FRA INITIATE INSPECTIONS OF EXCESS FLOW VALVES AND TAKE CORRECTIVE ACTION. I AM WRITING TO INFORM YOU OF OUR EFFORTS IN THIS REGARD. THE AAR TANK CAR COMMITTEE HAS ESTABLISHED, VIA DOCKET T50.14-84, A TASK FORCE REQUIREMENT TO INSPECT AND DETERMINE THE EXTENT OF THE PROBLEM OF LOOSE EXCESS FLOW VALVES. THE TASK FORCE HAS COMPLETED THEIR INITIAL INSPECTION PROGRAM. A TOTAL OF 998 TANK CAR TANKS WERE INSPECTED, FOR A TOTAL OF 2,994 EXCESS FLOW VALVES (3 PER TANK CAR). OF THIS TOTAL, 0.9 PERCENT WERE CONSIDERED TO BE DISENGAGED AND 7.2 PERCENT MORE WERE FOUND TO BE LOOSE. THE FRA AND THE AAR TANK CAR COMMITTEE ARE CONCERNED THAT A SIGNIFICANT NUMBER OF VALVE SEATS IN THIS STUDY REQUIRED TIGHTENING. AT THEIR MARCH 1985 MEETING, THE AAR TANK CAR COMMITTEE ADOPTED THE FOLLOWING MEASURES TO ADDRESS THIS PROBLEM AND TO REQUIRE A REINSPECTION OF THE ENTIRE FLAMMABLE GAS TANK CAR FLEET: 1. A CIRCULAR LETTER IS TO BE ISSUED TO ITS MEMBERS AND PRIVATE TANK CARS OWNERS TO THE EFFECT THAT EXCESS FLOW VALVES HAVING THREADED VALVE SEATS, ON ALL TANK CARS USED TO TRANSPORT A FLAMMABLE GAS, MUST BE CHECKED FOR TIGHTNESS AND TIGHTENED AT THE NEXT TANK OR SAFETY VALVE RETEST OR THE NEXT TIME THE CAR IS CLEANED. 2. AN APPROPRIATE GROUP (AAR TANK CAR COMMITTEE) IS TO REVIEW EXCESS FLOW VALVE DESIGN TO CONSIDER ELIMINATING SEPARABLE VALVE SEATS IN 2-INCH AND 3-INCH SIZES, OR PROVIDE A POSITIVE LOCKING DEVICE. 3. A REPRESENTATIVE SAMPLE OF THESE CARS CHECKED AND TIGHTENED IN ACCORD WITH THE AFOREMENTIONED CIRCULAR LETTER WILL BE REINSPECTED. THE TASK FORCE ON THIS MATTER WILL REPORT ON THE RESULTS OF THAT INSPECTION.

From: NTSB
To: FRA
Date: 8/28/1984
Response: The Federal Administration's (FRA) efforts to initiate excess flow valve inspections and to seek the cooperation of the industry in this matter are commendable. The Board's concern, as the FRA clearly states, is the danger of the flow valve becoming totally disengaged. If this should occur and the tank car were to be involved in an accident where the outer valve was sheared off, the contents of the tank car could be released, with a potential for a catastrophe. The Safety Board would appreciate being kept informed of the FRA and industry efforts, in particular the results of the Association of American Railroad's inspections and determination of the extent of the problem. Meanwhile, Safety Recommendation R-84-15 will be held in an "Open-Acceptable Action" status.

From: FRA
To: NTSB
Date: 6/6/1984
Response: FRA LETTER: THE FRA HAS CLOSELY EXAMINED THE EXCESS FLOW VALVE ISSUE. WHILE WE SHARE THE NTSB'S CONCERN THAT THE VALVES BE PROPERLY INSTALLED, THE FUNCTION OF THIS VALVE SHOULD BE CONSIDERED IN ITS PROPER PERSPECTIVE. THE ROLE OF THIS VALVE IS TO PERMIT THE CONTENTS TO FLOW FROM A TANK DURING UNLOADING OPERATIONS, AT UP TO 260 GALLONS PER MINUTE, AND TO STOP THE FLOW IN THE EVENT THE OUTER VALVE IS SHEARED OFF AND THE COMMODITY IS RELEASED AT A VERY HIGH RATE. THE TANK CAR INVOLVED IN THE BATON ROUGE ACCIDENT LOST ITS CONTENTS THROUGH A LEAK IN ITS LOADING PIPES, WHERE THE FLOW WAS NOT SUFFICIENT TO TRIGGER THE EXCESS FLOW VALVE. FRA ESTIMATED THE COMMODITY WAS RELEASED AT ABOUT 160 GALLONS PER MINUTE. FRA'S INVESTIGATION FOUND THAT AN INSECURE VALVE SEAT IS NOT LIKELY TO RESULT IN A TRANSPOR TATION ACCIDENT. FRA ALSO CONCLUDED THAT THE BATON ROUGE INCIDENT WOULD HAVE OCCURRED EVEN IF THE VALVE SEAT WAS FULLY SECURED AND THAT THE VALVE SEAT POSITION DID NOT CONTRIBUTE TO THE ACCIDENT. HOWEVER, FRA AGREES WITH THE NTSB THAT A PROBLEM EXISTS AND NEEDS TO BE CORRECTED. THE REAL DANGER IS THAT IF THE FLOW VALVE BECOMES TOTALLY DISENGAGED, THEN THE CONTENTS COULD BE RELEASED IF THE CAR WERE IN AN ACCIDENT WHERE THE OUTER VALVE WERE SHEARED OFF. ACCORDINGLY, THE FRA HAS TAKEN ACTION TO SEE THAT THE VALVES ARE PROPERLY SECURED. CONSISTENT WITH THE NTSB RECOMMENDA TION, FRA INITIATED ADDITIONAL EXCESS FLOW VALVE INSPECTIONS SHORTLY AFTER THE BATON ROUGE ACCIDENT. THESE INSPECTIONS CONFIRMED THE PRESENCE OF THE PROBLEM AND WE MADE OUR FINDINGS AVAILABLE TO BOTH THE UNION TANK CAR COMPANY AND THE ASSOCIATION OF AMERICAN RAILROADS, ALONG WITH A REQUEST THAT THEY ADDRESS THE ISSUE. THE UNION TANK CAR COMPANY ESTABLISHED A PROGRAM TO INSPECT THE FLOW VALVE SEATS ON THEIR CARS AND ISSUED INSTRUCTIONS TO ALL THEIR FACILITIES ON PROPER INSTALLATION REQUIREMENTS, THE AAR NOTIFIED THE CHIEF OPERATING AND MECHANICAL OFFICERS ON THE RAILROADS OF THE PROBLEM AND OF OUR MUTUAL CONCERN. SUBSEQUENTLY, THE AAR DEVELOPED A PLAN TO INSPECT AN ADDITIONAL 600 TO 700 CARS AND DETERMINE EXACTLY WHY THE VALVE SEATS WERE NOT FULLY SECURED. IN MARCH THE FRA ISSUED FOUR FOLLOWUP RECOMMENDATIONS TO THE AAR (COPY ENCLOSED). FRA HAS BEEN ACTIVELY WORKING WITH THE AAR TANK CAR COMMITTEE ON THE MATTER AND I ASSURE YOU THAT WE INTEND TO SEE IT THROUGH TO A SUCCESSFUL CONCLUSION. WHILE I AM CONVINCED THE INDUSTRY EFFORT WILL LEAD TO CORRECTION OF THE PROBLEM, FRA WILL REQUIRE THAT THE VALVES BE SECURED IF NECESSARY.