Ensuring Railroad Tank Car Safety Special Report 243 (1994) / Chapter Skim
Currently Skimming:
Pages 1-164
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 1... ...
Fittings Manway Housing Safety / .'VaIve Bottom Fittings NA NAE IC) M TRANSPORTATION RESEARCH BOARD National Research Council
|
From page 2... ...
1994 TRANSPORTATION RESEARCH BOARD EXECUTIVE COMMrVrEE Chairman: Joseph M Sussman, JR East Professor and Professor of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge Vice Chairman: Lillian C
|
From page 3... ...
Special Report 243 ENSURING RAILROAD TANK CAR SAFETY Committee for the Study of the Railroad Tank Car Design Process TRANSPORTATION RESEARCH BOARD National Research Council National Academy Press Washington, D.C.
|
From page 4... ...
Transportation Research Board Special Report 243 Subscriber Category VII rail Transportation Research Board publications are available by ordering directly from TRB. They may also be obtained on a regular basis through organizational or individual affiliation with TRB; affiliates or library subscribers are eligible for substantial discounts.
|
From page 5... ...
COMMITTEE FOR THE STUDY OF THE RAILROAD TANK CAR DESIGN PROCESS HERBERT H RICHARDSON, Chairman, Texas A&M University System, College Station ROBERT G
|
From page 6... ...
PREFACE SECTION 21 OF THE HAZARDOUS MATERIALS TRANS- portation Uniform Safety Act of 1990 [Public Law 101-615 (Nov.
|
From page 7... ...
vi Preface tion, the National Transportation Safety Board, Transport Canada, and the Association of American Railroads (AAR)
|
From page 8... ...
Preface vii Earl A Phillips, Director of the RPI-AAR Railroad Tank Car Safety Research and Test Project, briefed the committee on the project's data program and key research findings, and Christopher P
|
From page 9... ...
CONTENTS EXECUTIVE SUMMARY 1 INTRODUCTION 18 Background Issues, 20 Study Scope and Approach, 24 Report Organization, 25 2 TANK CAR DESIGN AND USE CHARACTERISTICS 28 Key Developments in Tank Car Design, 28 Principal Design Features, 31 Design Types, 40 Tank Car Use and Operational Characteristics, 46 Key Points and Findings, 56 3 TANK CAR REGULATION AND SAFETY PERFORMANCE 61 Tank Car Regulations, 61 Tank Car Safety Performance, 71 Key Points and Findings, 82
|
From page 10... ...
4 GOVERNMENT AND INDUSTRY ACTIVITIES TO ENSURE TANK CAR SAFETY 87 Government Activities, 87 Industry Activities, 93 Design Approval and Certification of Other Vehicle and Container Types, 103 Key Points and Findings, 107 S SUMMARY OF FINDINGS, KEY ISSUES, AND RECOMMENDATIONS 114 Summary of Process for Ensuring Tank Car Design Safety, 114 Tank Car Design and Safety Trends, 118 General Conclusions and Major Recommendations, 119 Other Recommendations and Issues, 130 APPENDIX A Regulatory Process Improvements in Other Agencies 137 APPENDIX B Glossary 142 STUDY COMMITTEE BIOGRAPHICAL INFORMATION 147
|
From page 11... ...
EXECUTIVE SUMMARY TANK CARS ARE A COMMON TYPE OF RAILCAR, AC- counting for about one in seven cars in the North American freight car fleet. Half the approximately 210,000 tank cars in North America carry materials regulated by the U.S.
|
From page 12... ...
2 ENSURING RAILROAD TANK CAR SAFETY aspects of tank car design, including the capability of existing tank cars to resist punctures and other damage during derailments and crashes. Congress requested a study of the overall process for ensuring tank car design safety and, more specifically, whether all tank cars carrying hazardous materials should be equipped with special safety devices, known as "head shields," to prevent tank car head (end)
|
From page 13... ...
Executive Summary 3 THERMAL PROTECTION The most common thermal protection system consists of a special insulation material (A) covered by a steel jacket (B)
|
From page 14... ...
4 ENSURING RAILROAD TANK CAR SAFETY by more than 90 percent after head protection and double-shelf couplers were installed on flammable gas cars starting in the late 1970s. Tank ruptures also declined dramatically after the introduction of thermal protection on, these cars.
|
From page 15... ...
Executive Summary S ments for the design of tank cars used in hazardous materials service. Its regulations provide design criteria, known as DOT specifications, for more than three dozen tank car types.
|
From page 16... ...
DOT ROLE AAR/TCC ROLE Design Standards DOT sets TCC assists in minimum design setting technical requirements for criteria and design safety I I I details Compliance with P _ _ Design Standards I TCC approves design DOT officials plans and repair and participate in TCC construction methods. activities, providing Standards manual, oversight of TCC service trials, and other approvals q IF activities enhance -- -•1 Inspection and con-phance certification of completed 14 r • work by builder L J FRA periodically s shops inspects shops, Fsetsdelines railroads, and uality shippers grams Authorization and use of design types to carry hazardous materials TCC and shippers DOT assigns determine lining materials to matedalsvalves, and design types -- -- - other special features I Shipper ensures use of i of tank car used P Iauthorized design I - - - - - - - - FIGURE ES-2 Summary of major elements in process for ensuring tank car design safety.
|
From page 17... ...
Executive Summary 7 trials of new tank car components and reviews proposed methods of construction and repair. Each of these activities increases the probability that completed tank cars will meet DOT specifications.
|
From page 18... ...
8 ENSURING RAILROAD TANK CAR SAFETY cars equipped with head and thermal protection, and poison gases are assigned to head-protected cars. Most other compressed gases can be transported in pressure cars without these protective features.
|
From page 19... ...
Executive Summary 9 ranging from monitoring tank car safety performance and researching safety improvements to instituting safety standards and ensuring their implementation. These roles are performed most constructively when accompanied by coordination and planning.
|
From page 20... ...
10 ENSURING RAILROAD TANK CAR SAFETY result of a long-term program for advancing safety but tends to be initiated in response to individual petitions for rule changes, legislative mandates, and major incidents. The regulatory process must be capable of responding to safety developments as they arise, but an overly reactive approach can perpetuate the need for incremental and ad hoc solutions to safety problems.
|
From page 21... ...
Executive Summary 11 and hazardous materials research. Partly because of limited resources, FRA's research program focuses on the immediate problems of current rulemaking and enforcement.
|
From page 22... ...
12 ENSURING RAILROAD TANK CAR SAFETY AAR and other industry groups also collect data on tank cars. The data range from tank car repair and inspection records to traffic information and accident reports.
|
From page 23... ...
Executive Summary 13 features (individually and in combination) in protecting hazardous shipments.
|
From page 24... ...
14 ENSURING RAILROAD TANK CAR SAFETY forces. A clearer definition of DOT's scope of responsibility in ensuring the safety of shipments by tank car is an essential first step in coordinating such programs.
|
From page 25... ...
Executive Summary iS There are more than 200 references to the TCC in the DOT regulations. These references, in addition to several DOT and AAR memoranda of understanding and legal clarifications, provide the basis for the approval authorities.
|
From page 26... ...
16 ENSURING RAILROAD TANK CAR SAFETY ensure that TCC actions implementing the authorities of greatest importance to safety are regularly monitored by FRA and RSPA officials and reviewed by outside technical experts as necessary. Informal arrangements that now provide FRA and RSPA (as well as Transport Canada and NTSB)
|
From page 27... ...
Executive Summary 17 a larger proportion of hazardous materials traffic moved by rail is now shipped in tank containers that are also transported by truck, barge, and ship. Because the use of intermodal tanks in rail is relatively new in the United States, experience in ensuring their safety in the rail environment is limited, especially compared with more than 100 years of experience in providing tank car safety.
|
From page 28... ...
CHAPTER 1 Introduction FOR MORE THAN A CENTURY, RAILROAD TANK CARS HAVE transported bulk liquids and compressed (liquefied) gases in the United States and Canada.
|
From page 29... ...
Introduction 19 and alloys of aluminum or nickel. All tank cars have openings fitted with valves and other closures, known as fittings, used for loading, unloading, pressure relief, tank maintenance, and cargo monitoring.
|
From page 30... ...
20 ENSURING RAILROAD TANK CAR SAFETY rials Safety, establishes the hazardous materials regulations covering shipments in most transport modes and container types, including railroad tank cars. The regulations govern tank car design, construction, repair, and maintenance; handling and operations by shippers and railroads; placarding and labeling; and use in transporting the various types of hazardous materials.
|
From page 31... ...
Introduction 21 incidents during the 1960s and 1970s, only one death has occurred since the beginning of the 1980s. The decline in fatalities has been impressive, but tank car incidents still occur and are cause for concern.
|
From page 32... ...
22 ENSURING RAILROAD TANK CAR SAFETY DOT is currently addressing most of these issues in rulemaking (Federal Register 1993a)
|
From page 33... ...
Introduction 23 representatives did not participate in TCC meetings; however, the team did not make recommendations concerning this matter because participation by FRA and RSPA staff had improved considerably during the audit period. DOT has indicated satisfaction with the actions taken by TCC in response to the audit recommendations and those of NTSB.
|
From page 35... ...
Introduction 25 published in time for committee evaluation. Nevertheless, the committee decided at the outset of the study that it could not properly assess the need for head protection on individual tank car designs and for specific types of hazardous materials.
|
From page 36... ...
26 ENSURING RAILROAD TANK CAR SAFETY 4. See Chapter 3 for tank car release statistics.
|
From page 37... ...
Introduction 27 GAO.
|
From page 38... ...
CHAPTER 2 Tank Car Design and Use Characteristics BACKGROUND INFORMATION ON THE DESIGN AND OPER- ating characteristics of railroad tank cars is reviewed in this chapter. A brief history of key developments in tank car design is followed by a review of principal tank car design features and major design types.
|
From page 39... ...
Tank Car Design and Use Characteristics 29 rials, including acids, alcohols, ammonia, and food products, were shipped in the growing and increasingly diverse tank car fleet. Establishment of Design Standards In the years before World War I innovations were made in tank car design to accommodate the expanding number of industrial chemicals being shipped by rail.
|
From page 40... ...
30 ENSURING RAILROAD TANK CAR SAFETY were based on specifications established previously by industry.3 The specifications governed tank wall thickness, construction materials, pressure relief systems, and various other design features. Key Technical Advances Before World War II, new specifications for heavier "pressure" cars were introduced to enable the transportation of chlorine and volatile flammable products such as liquefied petroleum gas (LPG)
|
From page 41... ...
Tank Car Design and Use Characteristics 31 size [34,500 gal (130 583 L)
|
From page 42... ...
Fittings Manway upler Lfl11t¼) I II I I I.J¼flS Fittings Assembly FIGURE 2-1 Principal design elements of nonpressure tank car (NTSB 1991)
|
From page 43... ...
Tank Car Design and Use Characteristics 33 from the corrosive or reactive effects of the cargo. Linings are made of glass and rubber and coatings usually consist of sprayed-on organic materials.
|
From page 44... ...
34 ENSURING RAILROAD TANK CAR SAFETY Top loading/unloading valve Bottom outlet valve Safety relief valves FIGURE 2-2 Examples of tank car valves (Union Pacific Railroad 1990)
|
From page 45... ...
Full-length center sill underframe Truck assembly FIGURE 2-3 Tank car underframe and running gear (Union Pacific Railroad 1990)
|
From page 46... ...
36 ENSURING RAILROAD TANK CAR SAFETY Safety Systems Depending on the design of the tank car and the commodity carried, U.S. Department of Transportation (DOT)
|
From page 47... ...
Tank Car Design and Use Characteristics 37 STANDARD COUPLERS AAR Type E Coupler Ier DOUBLE-SHELF COUPLERS USED ON TANK CARS Top Shelf TL A AAR Type E Top and Bottom Shelf Coupler Bottom Shelf Top Shelf and Bottom Bottom Shelf FIGURE 2-4 Standard freight car couplers and tank car double-shelf couplers (NTSB 1980)
|
From page 48... ...
Head protectior for pressure tar Skid protection device for bottom fitting of nonpressure tank car Protective housing for fittings on pressure tank car Protective housing FIGURE 2-5 Examples of tank car safety features (Union Pacific Railroad 1990)
|
From page 49... ...
Tank Car Design and Use Characteristics 39 responders had arrived at the scene and were near the weakened tank. The purpose of thermal protection is to retard heat flow into the tank when exposed to fire, providing emergency responders additional time to isolate the area, cool the tank, and begin to control the fire before the pressure in the tank exceeds the residual strength of the tank walls.
|
From page 50... ...
40 ENSURING RAILROAD TANK CAR SAFETY (Figure 2-5)
|
From page 51... ...
Tank Car Design and Use Characteristics 41 EXPLANATION OF TANK CAR DESIGN SPECIFICATION NUMBERS (General American Transportation Corporation 1991) DOT 111 A 60 AL W Welded construction Construction metal other than steel (alumi- num)
|
From page 52... ...
42 ENSURING RAILROAD TANK CAR SAFETY EXPLANATION OF TANK CAR DESIGN SPECIFICATION NUMBERS (General American Transportation Corporation 1991) (continued)
|
From page 53... ...
TABLE 2-2 North American Tank Car Fleet Statistics, 1993 SPECIFICATION NONPRESSURE° PRESSURE" SPECIALTY' Tomj. PERCENTAGE OF TOTAL DOT 159,974 49,348 631 209,953 98.7 AAR 2,668 0 113 2,781 1.3 Total 162,642 49,348 744 212,734 100 Percentage of Total 76.5 23.2 <1.0 100 - Nom: The figures include approximately 20,000 tank cars based in Canada that are accepted for interchange in the United States because they meet DOT or AAR requirements.
|
From page 54... ...
TABLE 2-3 North American Tank Car Fleet by DOT Specification Type and Year Built, 1993 YEAR BUILT PERCENTAGE DOT BEFORE 1964 TO 1974 TO AFTER OF TOTAL CLASS 1964 1973 1983 1983 TOTAL FLEET GENERAL DEscRIVrION OF Ciss 103 1,785 752 10 5 2,552 1.2 Steel, aluminum, nickel, or alloy steel tank with dome; some insulated 104 51 22 0 0 73 0 Insulated steel tank with dome lOS 2,222 4,726 12,178 6,744 25,870 12.3 Insulated steel tank for pressure service; some equipped with thermal and head protection 109 34 40 0 0 74 0 Aluminum tank for pressure service; some insulated 111 3,309 42,761 65,299 45,980 157,349 74.9 Steel, aluminum, or alloy steel tank without dome; some insulated 112 2,010 15,170 4,156 1,201 22,537 10.7 Noninsulated steel tank for pressure service; most equipped with head and thermal protection 113 6 83 32 0 121 0 Alloy steel tank with steel outer shell; heavily insulated to carry low-temperature commodities 114 83 609 18 20 730 0 Noninsulated steel tank for pressure service; many equipped with thermal and head protection 115 0 132 84 294 510 0 Insulated aluminum, steel, or alloy steel tank with outer shell 120 61 26 50 0 137 Q Insulated steel or aluminum tank for pressure service with optional bottom outlet Total 9,561 64,321 81,827 54,244 209,953 100 Percentage of total 4.6 30.6 39.0 25.8 100 - The 120 class has been proposed as a DOT specification but not approved. The DOT-120 tank cars currently in service operate under exemption.
|
From page 55... ...
Tank Car Design and Use Characteristics 45 Pressure Designs Pressure cars transport most of the compressed gases (materials maintained in a liquefied state by pressure) shipped in bulk by rail and make up about onequarter of the tank car fleet.
|
From page 56... ...
46 ENSURING RAILROAD TANK CAR SAFETY type 112s were designed to hold more than 40,000 gal (151 400 L) , which was more than 3 times the capacity of most other pressure cars at the time.
|
From page 57... ...
Tank Car Design and Use Characteristics 47 TABLE 2-4 Estimated Number of Tank Cars in Service in North America, 1993 HAzAiwous NoNI-LAzAiwous MATERIALS MATERIALS TYPE OF Teu'm Cit SERVICE SERVICE Tomi. Nonpressure 64,057- 98,585 162,642 Pressure 49,348 ob 49,348 Total 113,405 98,585 211,990 Percentage of Total 53 47 100 NcrrE: Specialty tank cars, of which there are fewer than 1,000, are not included in the table.
|
From page 58... ...
48 ENSURING RAILROAD TANK CAR SAFETY Carloads (thousands) 1OHp_ L01Ij 86 87 88 89 90 91 92 Year FIGURE 2-6 Annual shipments (carloads)
|
From page 59... ...
149,823 78,935 70,825 58,111 52,517 45,465 42,085 27,866 25,152 24.869 DOT-1OSJ, DOT-112J DOT-ill DOT-ill, AAR-21 i DOT-ill DOT-i 12S DOT-105A DOT-lu DOT-ill DOT-iOSJ, DOT-i 12J DOT-ili Flammable gas Corrosive Extreme heat (Class 9 Miscellaneous) Corrosive Nonflammable gas Poison gas Combustible liquid Flammable liquid Flammable gas Corrosive 575,648 954,000 60 Tank Car Design and Use Characteristics 49 TABLE 2-5 Top 10 Hazardous Commodities Shipped by Tank Car Type, 1992 (Bureau of Explosives 1993)
|
From page 60... ...
SO ENSURING RAILROAD TANK CAR SAFETY Poison Gas Nonflammable Gas (67000)
|
From page 61... ...
TABLE 2-6 Hazardous Materials Railroad Traffic by Region (Beier et al.
|
From page 62... ...
52 ENSURING RAILROAD TANK CAR SAFETY Leasing companies often supply hundreds of cars to a single shipper, who may find it more advantageous to lease than to own them. Lease periods usually range from 10 to 15 years, and monthly lease rates normally vary between $500 and $800.
|
From page 63... ...
Tank Car Design and Use Characteristics 53 Various practices are followed by shippers to ensure the quality of their tank car fleets. Many large shippers operate their own tank car maintenance and repair shops and employ tank car engineers to help design new tank cars and periodically inspect the fabrication and repair shops used to supply and service the fleet.
|
From page 64... ...
54 ENSURING RAILROAD TANK CAR SAFETY ensuring that tank cars arrive at their destinations safely, with the cargo intact, and within a reasonable period. The movement of a tank car (or group of cars)
|
From page 65... ...
Tank Car Design and Use Characteristics 55 cars in a train. DOT regulations prohibit placement of most placarded tank cars closer than six cars from a locomotive, except in short trains where alternative positioning is not possible.
|
From page 66... ...
56 ENSURING RAILROAD TANK CAR SAFETY The entire tank car trip can take from a few days to more than 2 weeks. The time period will depend on the distances involved, the priority of the shipment, and the number of carriers used.
|
From page 67... ...
Tank Car Design and Use Characteristics 57 relatively small number of commodities account for most tank car hazardous materials traffic, tank cars carry hundreds of commodities with numerous hazard characteristics. Tank cars account for about threequarters of the hazardous materials traffic (measured in carloads)
|
From page 68... ...
58 ENSURING RAILROAD TANK CAR SAFETY were designed with expanded tank centers (with a center diameter larger than the tank's head diameters) to provide additional carrying capacity for lowdensity commodities.
|
From page 69... ...
Tank Car Design and Use Characteristics 59 A major difference in the specifications is that AAR tank cars are not subject to full postweld heat treatment or radioscopic weld examinations. About 10 percent of these tank cars are based in Canada.
|
From page 70... ...
60 ENSURING RAILROAD TANK CAR SAFETY Bureau of Explosives.
|
From page 71... ...
CHAPTER 3 Tank Car Regulation and Safety Performance REGULATIONS GOVERNING THE DESIGN, CONSTRUCTION, and maintenance of railroad tank cars and their use in transporting hazardous materials are reviewed in this chapter. This is followed by review of the safety record of tank cars and the safety performance of individual design types, including those equipped with head protection.
|
From page 72... ...
62 ENSURING RAILROAD TANK CAR SAFETY setting bodies, such as the Bureau of Explosives (BOE) of the Association of American Railroads (AAR)
|
From page 73... ...
Tank Car Regulation and Safety Performance 63 Since passage of HMTA, DOT's responsibilities for hazardous materials safety have expanded. During the past two decades, several laws were passed requiring DOT to regulate the transport of substances and wastes classified by EPA as hazardous because of their potential to contaminate the environment and affect public health.1 The legislation caused hundreds of additional materials to be subject to DOT restriction during transportation.
|
From page 74... ...
TABLE 3-1 Examples of Design Criteria for Selected DOT Tank Car Specifications (49 CFR 179.101-1) DOT SPECIFICATION 112A200W 112A340W 112A400W 112A500W 114A340W 114A400W Insulation Optional Optional Optional Optional Optional Optional Bursting pressure (psi)
|
From page 75... ...
Tank Car Regulation and Safety Performance 65 Numerous provisions in the regulations require tank car builders and component makers to obtain TCC approval of tank car construction plans, designs of valves and other fittings, and methods of repair, alteration, and conversion. These provisions are intended to provide DOT with a means of ensuring industry compliance with the regulations.3 For design-specific regulatory requirements, the committee's role is fairly straightforward.
|
From page 76... ...
66 ENSURING RAILROAD TANK CAR SAFETY and other hazard information (e.g., placards and markings) are provided.
|
From page 77... ...
TABLE 3-2 General Packaging Requirements for Hazardous Materials Shipped in Bulk by Tank Car HAZARD CLAss DIVISION NAmE OF CLASS AND DMsI0N PACKING GROUP°/HAZARD ZONE TANK CARS AUTHORIZED 1 Explosive 2.1 Flammable Gas 2.2 Nonflammable Gas 2.3 Poisonous Gas Flammable and Combustible Liquids None None None Hazard Zones A and B (gases deemed highly poisonous based on measures of human inhalation toxicity) Hazard Zones C and D (poison gases that have comparatively lower human inhalation toxicity)
|
From page 78... ...
TABLE 3-2 ( HAZARD CLASS DivisioN 4.1 4.2 4.3 5.1 5.2 6.1 Flammable Solid Spontaneously Combustible Dangerous When Wet Oxidizer Organic Peroxide Poisonous Material (nongas) None PG I (pyrophoric liquids)
|
From page 79... ...
6.2 Infectious Substance 7 Radioactive 8 Corrosive 9 Miscellaneous ORM-D None None PG I, II, and III (corrosive materials that meet prescribed skin and metal corrosivity thresholds) Other regulated materials; mostly consumer products in limited quantities not conducive to bulk transportation None None PG I and II, essentially all DOT-class tank cars; PG III, non-DOT-class tank cars permitted Essentially all DOT- and non-DOTclass tank cars permitted Seldom applicable Dual-hazard nongas that poses Essentially all DOT-class tank cars moderate hazard (not meeting hazard criteria for PIH or 4.2 or 4.3 PG I)
|
From page 80... ...
70 ENSURING RAILROAD TANK CAR SAFETY for vapor toxicity are classified as "poison inhalation hazards" (PIH) and are restricted to pressure cars, which have thicker tank walls and betterprotected fittings than nonpressure cars.
|
From page 81... ...
Tank Car Regulation and Safety Performance 71 criteria for acute hazards (e.g., flammability or corrosivity) , in which case they must comply with restrictions for the applicable hazard class.
|
From page 82... ...
Incidents Carloads (000) 1400 - - - 1400 1200 1200 1000 - - 1000 800 800 600 .600 400 400 - Incidents LCarIoads II II Ii II II II II II Year 82 83 84 85 86 87 88 89 90 91 Deaths 0000010000 Injuries 32 66 71 50 53 22 31 36 66 62 FIGURE 3-1 Hazardous materials releases from tank cars reported to RSPA, 1982 to 1991 (RSPA 1983-1992; BOE 1988-1992)
|
From page 83... ...
Tank Car Regulation and Safety Performance 73 BOE also monitors tank car incidents, focusing on nonaccident releases of hazardous materials. When railroads report releases to RSPA, they send copies to BOE with additional information on release causes, consequences, and the types of cars involved.
|
From page 84... ...
74 ENSURING RAILROAD TANK CAR SAFETY accident and whether they sustained damaged and released product. The reports also provide basic information on the accident environment and circumstances, such as track type (e.g., mainline or yard)
|
From page 85... ...
Tank Car Regulation and Safety Performance 75 more than 35,000 records of tank cars damaged in accidents dating back to 1965.7 The records are highly detailed, indicating the number of cars involved in the accident, the type of track and train speed, tank car design type and placement in the train, the type of materials involved, the section or component of the tank car that sustained damage, and other information. The data base covers all tank cars, including those not in hazardous materials service, which account for about half the tank car fleet.
|
From page 86... ...
76 ENSURING RAILROAD TANK CAR SAFETY 1965-1979 to 1980-1986. In addition, the annual number of puncture and rupture releases among all tank car types (pressure and nonpressure)
|
From page 87... ...
Tank Car Regulation and Safety Performance 77 are associated with nonaccident release sources, such as leaks from valves and fittings (see Figures 3-2 and 3-3)
|
From page 88... ...
78 ENSURING RAILROAD TANK CAR SAFETY Percent of Total for All Tank Cars 100 .
|
From page 89... ...
Tank Car Regulation and Safety Performance 79 Annual Average Punctures/Ruptures 80.
|
From page 90... ...
TABLE 3-3 Major Protective Features of Tank Cars by Design Specification (Design Types with More Than 150 Cars in Service)
|
From page 91... ...
111A60ALW No/Alum.
|
From page 92... ...
82 ENSURING RAILROAD TANK CAR SAFETY from 1965 to 1979 (before the use of double-shelf couplers and head protection on most pressure cars) with accident records from 1980 to 1986 (RPI-AAR 1989)
|
From page 93... ...
TABLE 3-4 Accident Releases of Commodities Carried in DOT-i i2 Pressure Tank Cars Before and After Requirements for Special Protections (RPI-AAR 1989) AVERAGE AVERAGE AVERAGE HEi.D AVERAGE SHELL RUPTURES RUPTuRES PUNCI1JRE PUNCTURE FROM FROM AVERAGE COMMON TANK CAR RELEASES PER RELEASES PER IMPACT FIRE PER ANNUAL PERIOD TYPE USED YEAR YEAR PER YEAR YEAR TOTAL FLAMMABLE GAS 1965 to 1979 DOT-112A, DOT-105A 8.07 4.27 0.4 6.4 19.13 1980 to 1986 DOT-112J, DOT-105J 0.43 1.86 0.43 1.0 3.71 Percent change -94.7 -56.4 +7.5 -84.3 -80.6 ANHYDROUS AMMONIA 1965 to 1979 DOT-112A 1.33 0.8 0.33 0.07 2.53 1980 to 1986 DOT-112S 0.14 0.43 0 0.29 0.71 Percent change -89.5 -46.3 -100 +314 -71.9 FLAMMABLE GAS AND ANI-IYDROUS AMMONIA CorvIrnD 1965 to 1979 All above 9.4 5.07 0.73 6.47 21.66 1980 to 1986 All above 0.57 2.29 0.43 1.29 4.71 Percent change -93.9 -54.8 -41.1 -80.1 -78.3 Nom: DOT-i 12J and DOT-iOSJ type pressure tank cars are equipped with double-shelf couplers, head shields, and thermal protection; DOT-112S type tank cars are equipped with double-shelf couplers and head shields.
|
From page 94... ...
84 ENSURING RAILROAD TANK CAR SAFETY in-service tank cars are periodically reinspected and retested according to DOT requirements. DOT regulates the shipment of materials with acute safety hazards, assigning them to specific design types.
|
From page 95... ...
Tank Car Regulation and Safety Performance 8S tion, indicating the importance of double-shelf couplers and other safety improvements by railroads and shippers. Experience indicates that pressure cars, as a general class, are safer than nonpressure cars, but few systematic assessments have been made of the relative safety performance of individual design types.
|
From page 96... ...
86 ENSURING RAILROAD TANK CAR SAFETY 10. The precise effect is not known because overall improvements in rail safety and changes in tank car population and traffic have affected the general incidence and severity of railroad accidents.
|
From page 97... ...
CHAPTER 4 Government and Industry Activities To Ensure Tank Car Safety GOVERNMENT AND INDUSTRY TANK CAR SAFETY programs and activities are reviewed in this chapter.
|
From page 98... ...
88 ENSURING RAILROAD TANK CAR SAFETY defining the requirements of shippers and carriers in handling hazardous shipments. Most of the enforcement and technical support for RSPA's hazardous materials regulations is provided by the individual modal agencies.2 In the case of railroad tank cars, FRA provides this support and also assists RSPA in formulating new regulations.
|
From page 99... ...
Government and Industry Activities To Ensure Tank Car Safety 89 hours) if the action will not adversely affect safety.
|
From page 100... ...
90 ENSURING RAILROAD TANK CAR SAFETY During the past S years, FRA issued more than 3,000 penalties for violation of hazardous materials regulations by railroads, shippers, and container manufacturers and repairers.5 Among the most common violations (resulting in fines typically between $2,000 and $10,000 per violation) were improperly secured closures on residue tank cars (e.g., loose valve and outlet closures)
|
From page 101... ...
Government and IndustryActivities To Ensure Tank Car Safety 91 work with officials from Canada and Mexico to ensure uniformity in tank car standards. Agency technical staff also represent DOT at meetings of AAR's TCC and other industry groups.
|
From page 102... ...
92 ENSURING RAILROAD TANK CAR SAFETY Since its founding in 1968, NTSB has investigated more than three dozen tank car incidents, resulting in more than 75 recommendations to DOT and industry. Since the 1970s, NTSB has advocated use of head and thermal protection on tank cars and has expressed concern about DOT's performance in addressing current safety problems and anticipating future ones.
|
From page 103... ...
Government and Industry Activities To Ensure Tank Car Safety 93 Transport Canada regulations governing tank cars duplicate the U.S. regulations.
|
From page 104... ...
94 ENSURING RAILROAD TANK CAR SAFETY hazardous materials research in its Research and Test Department and through participation in interindustry research and technical activities. A chief responsibility of AAR is to institute railroad industry rules (interchange rules)
|
From page 105... ...
Government and Industry Activities To Ensure Tank Car Safety 95 companies or respective industry associations. Members usually have expertise in railroad operations, tank car and railcar engineering, or hazardous materials regulation and transportation.
|
From page 106... ...
Tank car builder applies by sending construction drawings to AAR Tank Car Committee AARITCC cI Wa + ' I m I I I I Tank Car Committee member 0 distribution and review DOT requirements checked AAR requirements checked AAR Certificate of construction New car construction FIGURE 4-1 Tank car design plan approval process (NTSB 1987)
|
From page 107... ...
Government and Industry Activities To Ensure Tank Car Safety 97 each committee member receives copies of the construction drawings and supporting evidence submitted by the builder (e.g., test results)
|
From page 108... ...
98 ENSURING RAILROAD TANK CAR SAFETY would use materials or procedures that have not previously been approved by the TCC, the builder or repairer must obtain TCC approval. This process is similar to that for construction of a new tank car.
|
From page 109... ...
Government and Industry Activities To Ensure Tank Car Safety 99 design, use, and operations, as well as emerging technologies and innovations. Revise AAR tank car specifications manual: The TCC is responsible for modifying the procedures, standards, and guidelines in the AAR tank car specifications manual.
|
From page 110... ...
100 ENSURING RAILROAD TANK CAR SAFETY BOE BOE, an organizational unit of AAR, was created by the railroads in 1907 to set standards for shipping explosives and other dangerous materials.18 During ICC's tenure in charge of hazardous materials regulation, BOE served as the agency's technical arm by classifying hazardous materials, testing packaging, and investigating major incidents. BOE's role in many of these areas has diminished over the past 25 years, but it still provides services to industry and government.
|
From page 111... ...
Government and Industry Activities To Ensure Tank Car Safety 101 operating procedures that minimize the risk of shipping hazardous materials by rail. For more than a dozen years, the Research and Test Department has managed DOT's Transportation Test Center in Pueblo, Colorado.
|
From page 112... ...
102 ENSURING RAILROAD TANK CAR SAFETY major tank car suppliers -- advises the RPI representative who serves on the TCC. In cooperation with AAR, RPI provides funding for the RPI-AAR Railroad Tank Car Safety Research and Test Project, which has made significant contributions to tank car crashworthiness during the past two decades.
|
From page 113... ...
Government and Industry Activities To Ensure Tank Car Safety 103 recommended operating practices. They also led to recommendations for better employee training in handling hazardous materials and for inspecting loaded tank cars to ensure that they are well secured.
|
From page 114... ...
104 ENSURING RAILROAD TANK CAR SAFETY shop facility for compliance with ASME standards. ASME requires shop recertification reviews every 3 years.
|
From page 115... ...
Government and Industry Activities To Ensure Tank Car Safety lOS they cross national borders and may be transported by ship, truck, and rail, in the United States regulations governing their design and construction are established and enforced principally by RSPA (rather than individual modal agencies) , in concert with international standards.
|
From page 116... ...
106 ENSURING RAILROAD TANK CAR SAFETY Aircraft design approval begins when FAA receives an application from the manufacturer requesting a design "type" certificate. Manufacturers of large aircraft initiate the process several years before construction begins, submitting thousands of design drawings, test results, and engineering reports to FAA.
|
From page 117... ...
Government and Industry Activities To Ensure Tank Car Safety 107 tank cars, certification of the completed car is the responsibility of the tank car builder rather than the TCC. The design approval process for cargo tanks and intermodal tank containers, which resemble tank cars more closely in cost and design complexity, also have similarities with the approval process for tank cars.
|
From page 118... ...
TABLE 4-1 Summary of Approval and Certification Processes for Tank Cars and Other Vehicles and Containers CARGO TANK (TANK INTERMODAL TANK COMMERCIAL TANK CAR TRUCK) CONTAINER TANK VESSEL AIRCRAFT Principal regulatory responsibility Review and approval of design plans for regulatory compliance Inspection and certification of completed work RSPA promulgates rules; FRA assists in their formulation and enforces them AAR TCC approves plans for design and construction under DOT authorization.
|
From page 119... ...
Certification of construction and repair facilities sends AAR the certificate of construction Builder/repairer must be certified by AAR ICC and AAR Quality Assurance Committee. Qualification requirements govern work force, equipment, and shop procedures.
|
From page 120... ...
110 ENSURING RAILROAD TANK CAR SAFETY active in this regard, most notably in sustaining data programs in support of research to improve tank car crashworthiness. FRA and industry sometimes collaborate in conducting individual tank car research and test projects.
|
From page 121... ...
Government and Industry Activities To Ensure Tank Car Safety 111 the assistance of private-sector and nongovernmental bodies to review construction drawings, certify completed work, and qualify construction and repair shops. Most regulatory agencies cannot maintain the technical staff and resources necessary to perform these functions.
|
From page 122... ...
112 ENSURING RAILROAD TANK CAR SAFETY by the Superfund Amendments and Reauthorization Act of 1986. CERCLA requires that the materials listed as hazardous because of these statutes be regulated as hazardous materials under the Hazardous Materials Transportation Act.
|
From page 123... ...
Government and Industry Activities To Ensure Tank Car Safety 113 REFERENCES ABBREVIATIONS AAR Association of American Railroads BOE Bureau of Explosives NTSB National Transportation Safety Board RSPA Research and Special Programs Administration AAR.
|
From page 124... ...
CHAPTER S Summary of Findings, Key Issues, and Recommendations THE KEY ELEMENTS OF THE PROCESS FOR ENSURING TANK car design safety are summarized in this chapter. This is followed by a general assessment of the safety record of tank cars and the effectiveness of the process for ensuring safety.
|
From page 125... ...
DOT ROLE AAR/TCC ROLE Design Standards DOT sets TCC assists in minimum design setting technical requirements for criteria and design safety I I I details ____________ Compliance with _________ Design Standards T TCC approves design DOT officials plans and repair and participate in TCC construction methods. activities, providing Standards manual, oversight of TCC servce trials, and other approvals 14 IF activities enhance -- -pect -- - a-nd corçliance certification of completed It • work by builder FRA periodically alifies shops inspects shops, Fands guidelines railroads, and op quality shippers l programs Authorization and use of design types to carry hazardous materials TCC and shippers DOT assigns determine lining materials to matenalsbvalves, and design types -- -- -- - other special features I Shipper ensures use of i of tank car used ,I authorized design I -- -- -- -- _J FIGURE 5-1 Summary of major elements in process for ensuring tank car design safety.
|
From page 126... ...
116 ENSURING RAILROAD TANK CAR SAFETY more than three dozen tank car types. Except for some specialized tank cars, most designs are one of two general types: pressure or nonpressure.
|
From page 127... ...
Summary of Findings, Key Issues, and Recommendations 117 with DOT requirements. TCC approval of construction plans, required by DOT, functions as a peer review, reducing the potential for error through expert appraisal.
|
From page 128... ...
118 ENSURING RAILROAD TANK CAR SAFETY the necessary lining, construction materials, and other design features that ensure lading compatibility. The most significant exception is that some poison liquids with high vapor toxicity (deemed poison by inhalation)
|
From page 129... ...
Summary of Findings, Key Issues, and Recommendations 119 tank cars damaged in train derailments, collisions in switching yards, and other accidents. Most tank car releases consist of small spills and leaks occurring under nonaccident circumstances.
|
From page 130... ...
120 ENSURING RAILROAD TANK CAR SAFETY changing safety concerns and needs. Nevertheless, further modifications of the process are warranted, as public safety concerns, the environment in which tank cars operate, and the types of materials shipped by tank car continue to change.
|
From page 131... ...
Summary of Findings, Key Issues, and Recommendations 121 actions to attain them. The plan should be developed in cooperation with industry, labor, and other interested parties to elicit their expertise and perspectives.
|
From page 132... ...
122 ENSURING RAILROAD TANK CAR SAFETY circumstances. Unfortunately, the method by which regulations are developed can hinder cooperation between DOT and industry.
|
From page 133... ...
Summary of Findings, Key Issues, and Recommendations 123 to the railroad operating environment (such as train operations, track and railcar conditions, and switching practices)
|
From page 134... ...
124 ENSURING RAILROAD TANK CAR SAFETY data programs and those of industry. DOT should establish a safety data work group consisting of representatives of industry, government agencies, and other organizations that submit, maintain, and use the data.
|
From page 135... ...
Summary of Findings, Key Issues, and Recommendations 125 nature of the information and the difficulties of obtaining data from several sources with varying formats, definitions, and data management systems can impede access. Poor coordination of data programs has resulted in data gaps.
|
From page 136... ...
126 ENSURING RAILROAD TANK CAR SAFETY crash tests, accident modeling, and other quantifiable measures should be used to rate the safety performance of design types. Results from these performance assessments should be used to determine whether the current regulatory assignment of hazardous materials to design types is acceptable and whether some commodities warrant reassignment to safer cars.
|
From page 137... ...
Summary of Findings, Key Issues, and Recommendations 127 nation) in protecting hazardous shipments.
|
From page 138... ...
128 ENSURING RAILROAD TANK CAR SAFETY The degree of coordination between EPA and DOT, as well as other federal agencies charged with aspects of hazardous materials control, was recently evaluated by an interagency task force. The task force reported wide variations in criteria used to regulate hazardous materials and poor links between agencies for coordinating technical, research, and data activities (National Response Team 1992)
|
From page 139... ...
Summary of Findings, Key Issues, and Recommendations 129 Clearly and Thoroughly Describe TCC Approval Authorities RECOMMENDATION 6: DOT should define the TCC's mission and scope of responsibility with respect to the approval authorities, preferably in a DOT policy statement or in a single place in the hazardous materials regulations. The rationale for the authorities, the significance of each, and the nature of DOT's oversight role should be explained.
|
From page 140... ...
130 ENSURING RAILROAD TANK CAR SAFETY of subcommittees and work groups often take several years to complete. Design plan approvals can be delayed by several weeks, which is costly to tank car suppliers and shippers.
|
From page 141... ...
Summary of Findings, Ke.y Issues, and Recommendations 131 that were sufficiently well defined for consideration and that the committee believes merit further action. Ensure Broad Compliance with Construction, Maintenance, and Repair Standards RECOMMENDATION 9: To ensure the most effective use of its limited enforcement capabilities, FRA should identify tank car regulatory areas that have high potential for noncompliance and significance to safety.
|
From page 142... ...
132 ENSURING RAILROAD TANK CAR SAFETY Develop a Comprehensive Approach To Providing Grandfather Exclusions RECOMMENDATION 10: FRA and RSPA should develop formal policies and guidelines governing decisions to exclude -- for economic or technical reasons -- existing tank cars from compliance with requirements for major new safety features and modifications. Consideration should be given to providing limits on the time period of the exclusion, restrictions on the use of excluded tank cars in hazardous materials service, and other options aimed at ensuring that the intended safety benefits of the new requirement are achieved at the least cost.
|
From page 143... ...
Summary of Findings, Key Issues, and Recommendations 133 that thorough and explicit consideration is given to all plausible implementation alternatives (e.g., delayed compliance periods and handling or routing restrictions) and their relative cost and safety effects.
|
From page 144... ...
134 ENSURING RAILROAD TANK CAR SAFETY of hazardous materials traffic moved by rail is shipped in tank containers that are also portable by truck, barge, and ship. These intermodal containers are usually loaded on railroad flatcars and contain many of the same commodities as tank cars, although in smaller quantities [6,000 gal (22 800 L)
|
From page 145... ...
Summary of Findings, Key Issues, and Recommendations 135 between agency staff and the public during rulemaking, and sometimes before the initiation of rulemaking activity (Petrie et al.
|
From page 146... ...
136 ENSURING RAILROAD TANK CAR SAFETY Barkan, C., T Glickman, and A
|
From page 147... ...
APPENDIX A Regulatory Process Improvements in Other Agencies ON SEPTEMBER 7, 1993, VICE PRESIDENT Ai. GoRE presented the findings of the National Performance Review, a 6-month study to identify measures to improve the effectiveness and efficiency of federal government services and programs.
|
From page 148... ...
138 ENSURING RAILROAD TANK CAR SAFETY Use information technology and other techniques to increase opportunities for early, frequent, and interactive public participation during the rulemaking process and to increase program evaluation efforts. Streamline internal agency rulemaking procedures.
|
From page 149... ...
Regulatory Process Improvements in Other Agencies 139 federal and state governments, a description of the communications media to use for soliciting comments from these parties (e.g., mail, Federal Register, press releases, computer bulletin boards, and public meetings) , and a recommendation of the comment period required to give respondents time to provide input.
|
From page 150... ...
140 ENSURING RAILROAD TANK CAR SAFETY improvement. There was concern that the process was neither timely nor responsive to the public.
|
From page 151... ...
Regulatory Process Improvements in Other Agencies 141 REFERENCES Federal Register.
|
From page 152... ...
APPENDIX B Glossary This appendix explains several key terms used in the report. TANK CAR DESIGN TERMS Attachments: Handrails, ladders, body bolsters, and other components connected to pads welded to the tank exterior.
|
From page 153... ...
Glossary 143 construction material, although some tanks are made of aluminum and nickel alloys and stainless steel. Tank capacities range from less than 10,000 gal to 34,500 gal.
|
From page 154... ...
144 ENSURING RAILROAD TANK CAR SAFETY to encourage continued development by industry of new safety improvements and to avoid imposing severe economic burdens on tank car owners and operators by requiring modification or replacement of existing tank cars not equipped with the new safety feature. Hazard classes and divisions: DOT system for classifying materials according to physical and hazard characteristics.
|
From page 155... ...
Glossary 145 Placards and labels: DOT requires shippers to communicate the hazards of their shipments by affixing appropriate diamond-shaped signs (placards) and labels with identifiers and symbols of hazards on containers and packages.
|
From page 156... ...
146 ENSURING RAILROAD TANK CAR SAFETY valves and other components, methods of repair and alteration, and construction and repair facilities. Interchange rules: Rules governing railcar dimensions and other design features.
|
From page 157... ...
STUDY COMMITTEE BIOGRAPHICAL INFORMATION Herbert H Richardson, Chairman, is Director of the Texas Transportation Institute and Associate Vice Chancellor for Engineering, Texas A&M University System.
|
From page 158... ...
148 ENSURING RAILROAD TANK CAR SAFETY ing, where he previously served as Provost and Vice President of Academic Affairs. He began his academic career at the University of Rochester, where he was Professor of Mechanical and Aerospace Sciences, Dean of the College of Engineering and Applied Sciences, and Director of the Space Science Center.
|
From page 159... ...
Study Committee Biographical In formation 149 George P Binns is Senior Director of Equipment Design Engineering for the National Railroad Passenger Corporation (Amtrak)
|
From page 160... ...
150 ENSURING RAILROAD TANK CAR SAFETY Lemoine V Dickinson, Jr., is Senior Associate at Failure Analysis Associates.
|
From page 161... ...
Study Committee Biographical In formation 151 Henry B Lewin is General Vice President and National Legislative Representative of the Brotherhood of Railway Carmen Division of the International Transportation Communications Union.
|
From page 162... ...
152 ENSURING RAILROAD TANK CAR SAFETY ber of the National Fire Protection Association's LPG Committee and the Editorial Board of the Journal of Hazardous Materials. He has held the post of visiting lecturer at MIT and was an invited speaker at the von Karman Institute in Brussels.
|
From page 163... ...
The Transportation Research Board is a unit of the National Research Council, which serves the National Academy of Sciences and the National Academy of Engineering. The Board's purpose is to stimulate research concerning the nature and performance of transportation systems, to disseminate the information produced by the research, and to encourage the application of appropriate research findings.
|
From page 164... ...
> Lc 00 F 64 ISBN 0-309-05518-0 1 Z National Academy Press
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.