According to AAR, hazardous materials comprise about 8 percent of commodities shipped by rail in North America—about 2.35 million out of 29.4 million annual carloads shipped in 2015. According to the most recent Bureau of Transportation Statistics data available (2012), railroads ship about 4 percent of the hazardous materials in the United States by tonnage, but railroad shipments account for about 28 percent of distance traveled by hazardous materials. The freight railroad industry is dominated by the seven Class I railroads, which transport the majority of freight—including hazardous materials—in freight containers, portable tanks, and other types of rail cars, including tank cars that travel across a network of 140,000 miles of track. In addition, numerous Class II and hundreds of Class III railroads have essential roles in moving freight, typically linking rural communities to the larger railroad network. Often providing “first mile” and “last mile” movements, these smaller railroads, taken together, operate on 50,000 miles of track or nearly 40 percent of the national railroad network and handle in origination or destination one of every four cars moving on the national system. PHMSA, through its Office of Hazardous Materials Safety, regulates shippers and railroads transporting hazardous materials by rail and other modes. One way PHMSA fulfills this mission is through the promulgation of the HMR for the safe transport of hazardous materials. These regulations pertain to the classifying, handling, and packaging of shipments of hazardous materials, including rail shipments, and include seven requirements that emergency response information must include for each hazardous material being shipped. These are: 1. The basic description and technical name of the hazardous material. 2. Immediate hazards to health. 3. Risks of fire or explosion. 4. Immediate precautions to be taken in the event of an accident. 5. Immediate methods for handling fires. 6. Initial methods for handling spills or leaks in the absence of fire. 7. Preliminary first aid measures. The HMR also require railroads to have a document, often referred to as the train consist, that identifies basic information about the position in the train of each rail car containing hazardous materials. The consist also typically includes information on the train’s contents, including basic descriptions of the hazardous materials transported, and their destinations, and may include supplemental emergency response information, such as details on how to respond to releases of specific hazardous materials. FRA provides regulatory oversight for passenger and freight rail, issuing and enforcing safety regulations through its Office of Railroad Safety. FRA enforces the HMR and its own regulations through inspections and audits by FRA officials, including about 400 federal safety inspectors and state partners in some states. For example, according to DOT officials, FRA conducts inspections to ensure that railroads carry the required emergency response information mentioned above as well as an emergency response telephone number in train documentation and conduct and keep records of required general-awareness and function- specific hazardous material training for train crews. When a rail accident occurs, local emergency responders—police, emergency medical technicians, and firefighters—and railroad train crews are typically first on the scene of, and often provide the initial response to, a rail accident involving hazardous materials. For example, local and sometimes regional officials may be responsible for advising the public on taking shelter-in-place actions or conducting evacuations of affected populations. In addition, assuming the crews are not affected by an accident, railroad train crews are expected to provide local emergency responders with information about the position, type, and quantity of hazardous materials on the train as well as written emergency-response and contact information for the specific commodities (see fig. 1). The HMR also requires railroads to provide immediate notice of certain hazardous materials accidents to the National Response Center. The ERG, published every 4 years by PHMSA, is a 400-page document that contains emergency response information for thousands of hazardous materials and for all modes of transportation. It is intended to help first responders identify the characteristics of the hazardous materials involved in an accident through a table of markings, labels, and placards, specific risks associated with the hazardous materials how first responders can protect themselves, and procedures for containing the accident as quickly and safely as possible. The ERG is organized into four color-coded sections to help users navigate the document. For example, the orange section of the ERG divides hazardous materials into 63 categories—such as flammable liquids-toxic, flammable gases, and oxidizers —with an individual guide for each that provides information on types of potential hazards each category poses, including health, fire, or explosion hazards. The green section provides specific information, such as initial isolation and protective action distances for small or large spills occurring during the day or night, for hazardous materials that are considered to be a toxic inhalation hazard (see fig. 2). To assist railroads in complying with the HMR, AAR, with the input of railroads, develops and makes available to all subscribing railroads the United States Hazardous Materials Instructions for Rail, which provides general guidelines to the train crew on handling hazardous material shipments or incidents safely and efficiently and in accordance with local, state, and federal regulations. For example, this document provides information on required emergency response information, how the train crew and emergency responders are to interact, and what to do when a fire or vapor cloud is visible. This document also recommends that train crews carry the ERG. Selected railroads typically carry two sources of emergency response information—the train documents and the ERG—to meet the emergency response information requirements in federal regulations. Our review of selected train documents determined that they always contained the position and content of rail cars and the basic descriptions of hazardous materials on board the train. In addition, our analysis determined that the train documents sometimes included supplemental emergency response information. Fifteen of the 18 railroads we spoke with told us that they use AAR’s United States Hazardous Materials Instructions for Rail as their guidance for meeting train documentation requirements, including emergency response information. According to the train crews’ unions, the ERG and the train documents are kept in the locomotive of the train by the train crew, usually a conductor and an engineer. According to FRA and PHMSA officials, the ERG’s use is not required by regulation, but is viewed by the rail industry as a national standard for emergency response information requirements. All railroads that we interviewed told us that the ERG is carried aboard its trains as a source of emergency response information. For shipments of hazardous materials, the HMR requires the train crew to carry documents with specific information about the hazardous materials on board. Our review of selected train documents showed that the selected railroads included this information in their train documents. Additionally, most of the selected railroads included the information in their train consist, which identifies the position in the train of each rail car and includes other information about the rail car, such as its contents and destination. This information includes a basic description of each hazardous material being transported on that train, including the identification number and proper shipping name, as well as an emergency response telephone number, which is provided by the shipper of the regulated hazardous material (see fig. 3). This telephone number is required to be located on documentation carried by the train crew on the shipping documents for transportation of the material. This basic description of the hazardous material the train is transporting meets the first of seven emergency-response information requirements in the HMR. Our review revealed that some railroads also include supplemental emergency response information for each hazardous material on the train at the end of the train consist or in a separate document. According to AAR, it provides this information to some railroads from its Hazardous Materials Emergency Response Database, which AAR develops and maintains. Six of the 7 Class I railroads and 5 of the 11 selected Class II and III railroads included this supplemental information in their trains’ documents. Our analysis showed that the amount and content of the supplemental emergency response information varied depending on the number and type of hazardous materials being transported on a train. For each hazardous material on the train, the information can include 5 to 10 paragraphs, covering 1 to 2 pages of paper. Supplemental emergency response information may include information on how to handle fires; precautions to be taken in the event of an accident; first aid responses; or how to handle air, water, or land spills for that particular hazardous material (rather than groups of hazardous materials as with the ERG). AAR told us the railroads carry this information because, prior to the development of the ERG, it was the only source of emergency response information carried on trains. However, as discussed later, AAR plans to discontinue the use of this database because, among other reasons, new sources of information, along with the ERG, have become available to emergency responders that contain this type of information. According to the four emergency response associations we spoke to, when responding to a rail accident involving hazardous materials, emergency responders primarily rely on information from the train documents and the ERG during the first 30 minutes. These associations and two local responders we spoke to told us that responders will want to immediately learn what hazardous materials are on the train and their exact location. There are a couple of ways a responder might begin to identify what is on the train. According to all selected responders, if the train crew is located quickly, responders would use the train documents to identify and locate the hazardous materials on the train. If the train crew is incapacitated or cannot be found right away, responders could use placards, labels, or markings on the train to identify the hazardous materials, according to one emergency response association. According to four emergency response associations, responders then may consult the ERG to gather more information about the hazardous materials. PHMSA, the four emergency response associations, and one local responder told us that the ERG is the go-to source for first responders during the first 30 minutes or initial phase of an accident.