A User’s Guide to 2004 U.S. DOT

Feb. 1, 2005

The 2004 edition of the U.S. Department of Transportation’s (DOT) Emergency Response Guidebook (ERG) has been published, marking its first revision since 2000. Designed by the DOT, Transport Canada and the Mexican Secretariat of Transport and Communications, the ERG is intended for use by first-responding emergency personnel to a suspected hazardous materials or terrorism incident.

Photo By Robert Burke Baltimore City firefighters reference the 2004 U.S. DOT Emergency Response Guidebook during an emergency involving a chemical release at the University of Maryland. The ERG is designed to help first-in emergency responders quickly identify specific or generic hazards of materials and protect themselves and the public during the initial response phase of a suspected hazmat or terrorism incident. The ERG should be used only during the initial-response phase of an incident (first 30 minutes). It is designed to aid first responders in quickly identifying the specific or generic hazards of the material or materials involved in an incident, and protecting themselves and the public.

To obtain the greatest benefit from the ERG, responders should become thoroughly familiar with it before it is needed during an emergency. The ERG is divided into four major color-coded sections: yellow, blue, orange and green. It includes a placard chart; numerical and alphabetical listings; action guides; protective action distances; water-reactive materials; protective clothing; a glossary; and miscellaneous information. For the new edition, information has been added or revised in the Road Trailer Chart, Intermodal Container Hazard Identification Codes, Toxic Inhalation Hazard (TIH), Isolation and Evacuation Distances, Who to Call for Assistance, Hazard Classification System, Table of Placards, Glossary, Emergency Response Telephone Numbers, and Criminal/Terrorist Use of Chemical/Biological Agents sections. The page section covering Criminal/Terrorist Use of Chemical/Biological (CB) Agents is designed to provide information to response personnel during the preliminary assessment of a potential terrorist incident involving chemical or biological agents. A list of observable indicators of the use and/or presence of a CB agent is provided on pages 354-357.

Once on a suspected hazmat or terrorist scene, first responders have four basic responsibilities: recognition, notification, isolation and protection. Most importantly, response personnel must protect themselves before taking any action. When they determine that a hazmat or terrorist event has occurred, they should access the ERG.

New pages were added to the 2000 edition of the ERG with silhouettes of rail cars and road trailers. The 2004 edition has one new addition to the Road Trailer Section, the DOT 407 vacuum-loaded tank. There are a wide variety of rail cars and road trailer vehicles that transport liquids, compressed gases, liquefied compressed gases, refrigerated liquids, flammable solids and molten solids.

Photo By Robert Burke Chemical names stenciled on containers or found in shipping papers or other sources can be researched in the blue section of the ERG. While the container type may indicate the physical state of the material inside, more identification is needed concerning the product before any mitigation efforts are initiated. The information presented in the ERG is designed to give responders a very generic idea of the hazards associated with certain bulk transportation containers. Orange guides have been provided for use depending on the type of container involved in an incident. They can be found in a circle next to individual rail cars and road trailers located on the charts. These guide pages should be used only when no other information is available about materials. The “Rail Car Identification Chart” is on page 18 of the ERG and the “Road Trailer Identification Chart” is on page 19.

Only when a four-digit ID number is not available and the name of the material is unknown, should responders refer to the table of placards in the front of the book on pages 16 and 17, for placards and labels displayed on containers and transportation vehicles. The placard table shows new placards used under the DOT regulations that were not shown in the 1996 guidebook, along with additional placards used in Canada and Mexico. In a circle next to each placard on the table is an action guide number from the orange section, which is used for materials displaying the placard shown. Several placards have been added or removed from the placard table in the 2004 edition. When a “dangerous” placard is displayed, guide 111 is used for mixed loads or unidentified cargo.

If the nature of the spilled, leaking or burning material is unknown, additional information must be obtained as soon as possible. Orange action guides in the ERG are grouped by hazard class and special information surrounding the shipment. A listing of hazard classes is on page 14. This listing corresponds with the hazard classes represented on the placard table.

Several hazard classes have been modified from the 2000 edition. Division 2.4 has been removed and three subclasses have been added to Division 9. They include the DOT’s placarding and labeling system identifying the most severe hazard of a material as determined by the regulatory agency. Note, however, that almost all hazardous materials can have more than one hazard. Responders should be aware of this fact and be prepared for “hidden hazards.”


The yellow section, which starts on page 25, lists United Nations four-digit ID numbers. These numbers are located in the center of placards on vehicles transporting bulk quantities of hazardous materials. Once the ID number is located in the yellow section of the guide, a reference is made to an action guide located in the orange section of the book. This action guide is identified with a three-digit number that appears at the top of the page. Three-digit numbers located in the yellow and blue sections of the guide may have a letter P after the number. This letter indicates that in addition to any other hazards the material may have, it also may undergo polymerization, which can be a violent explosive reaction.


Alphabetical listings of the same materials found in the yellow section are located in the blue section starting on page 105. This section is used only if the name of a hazardous material is known. Both the yellow and blue sections reflect new additions of chemicals not contained in the 2000 guidebook.

When a material listed in the yellow or blue section is highlighted, initial isolation and protective action distances for that chemical are listed in the green section, starting on page 318. The evacuation distances located in the green section of the book are used only if the material is not on fire. If a material is on fire, responders should consult the list of evacuation distances in the orange section.


Protective action guides numbered from 111 to 172 begin on page 169. Each protective action guide provides procedures designed to preserve the health and safety of the public and emergency response personnel during the initial stages of a hazmat incident. Emergency responders should become familiar with all sections of the guidebook before an incident occurs.

Once an orange guide page is identified for a particular chemical; read the entire page before taking any action. Actions taken should not exceed the level of training and equipment available to response personnel. The ERG is designed for first responders, who by federal law have a limited capability to deal with hazardous materials because of limited training and lack of proper chemical protective equipment.

Pages in the orange section are divided into three major sections: Potential Hazards, Public Safety and Emergency Response. The Potential Hazards section is subdivided into two sections: fire or explosion; and health hazards. Either the fire or explosion or the health hazards may appear first in the listing on the page. Whichever one is listed first indicates the most severe hazard of the material.

Public Safety is divided into three sections: General Information for Responders, Protective Clothing and Evacuation. Emergency Response is divided into three sections: fire, which includes evacuation and isolation information; recommended extinguishing agents; and when to use unmanned monitors and withdraw from the area. Also included in the orange section are spill or leak procedures and first-aid information. Several guides also contain loss-of-cooling information for materials that must be maintained at a certain temperature to remain stable. This applies primarily to organic peroxides, which have self-accelerating decomposition temperatures (SADT) and may polymerize if cooling is lost.


Initial isolation and protective action distances for highlighted materials in the yellow and blue sections are located in the green section, starting on page 302. An introduction to the Table of Initial Isolation and Protective Action Distances can be found on pages 300-301. The green section lists materials by ID number and TIH materials, and includes certain chemical warfare agents and water-reactive materials that produce toxic gases upon contact with water.

A TIH material is a liquid or a gas known to be so hazardous to humans that it poses a hazard to health during transportation or, in the absence of adequate data on human toxicity, is presumed to be toxic to humans based on tests conducted using laboratory animals. A TIH has an LC50 value of not more than 5,000 ppm, indicating the lethal concentration to 50% of the laboratory animals tested. Hazard zones have been assigned to TIH materials in an attempt to classify the severity of the inhalation hazard in terms of LC50. For example, a Hazard Zone A material would be more toxic than a Hazard Zone D material.

Many isolation and downwind distances were revised, both upward and downward, between the 1993, 1996 and 2000 editions of the ERG, and there have been additional adjustments in the 2004 edition. Fluctuations occur because of improvements in computer modeling, which is used to determine such distances.

A graphic showing set-up of initial isolation and protective action guide distances is on pages 300 and 301. When a material in the yellow or blue section is highlighted, responders should go directly to the green section to obtain isolation and evacuation distances.

Distances in the green section are divided into small spills and large spills. A small spill consists of a single individual package or container, usually 55 gallons or less in capacity. Large spills involve a large package or container, or multiple small packages or containers. Spills are further divided into day and night events. Day spills are considered any time between sunrise and sunset, and night spills anytime between sunset and sunrise. Isolation distances and downwind protection distances are identified for both day and night spills. This is done because the air is more stable at night and vapor clouds will travel farther than during the day.

Dangerous water-reactive materials are also listed at the end of the green section. These listings should be used only when materials are spilled in water or when firefighting will cause a water reaction. Types of toxic vapors released in a water reaction with listed water-reactive materials are identified in this section. The potential TIH gases released when water reactive materials are in contact with water also are shown.

Several new contact numbers have been added in the 2004 ERG. If the material spilled is a marine pollutant or if oil products are spilled on the water, the National Response Center (NRC) should be notified. If “RQ” is listed on the shipping papers, the material is a reportable quantity of the hazardous material and, if spilled, the NRC must be contacted. The NRC is the notification, communications, technical assistance, and coordination center for the National Response Team (NRT). It can provide information on chemicals through its OM-TADS database. The NRC can also provide facilities for conducting conference calls with over 20 different parties on the incident scene. NRC should also be contacted to report chemical or biological terrorist attacks.

Pages 11 and 372 of the ERG provide information about emergencies involving military shipments. Two contact numbers are provided: for explosives or ammunition incidents call 703-697-0218 (collect calls are accepted); and all other dangerous goods incidents should be referred to 800-851-8061. These numbers are for emergencies only. A glossary of terms is provided on pages 358 to 365.

Free copies of the ERG are provided by the DOT to all police, fire, EMS and other emergency response organizations through a selected agency in each state. Your state agency can be determined by contacting the DOT Office of Hazardous Materials Transportation Research and Special Programs (RSPA) at 202-366-0656. State contacts for the ERG are also listed on the DOT website at http://hazmat.dot.gov/gydebook.htm.

The author has developed a training course for the ERG available in a PowerPoint CD-ROM version. In addition, each CD contains an electronic version of the ERG, a DOT Chart 12, an instructor guide, a student manual, lists of state ERG contacts and private-sector sources, a certificate template and a final exam. Information may be obtained at [email protected], by fax at 410-760-2549 or at www.hazardousmaterialspage.com.

Robert Burke, a Firehouse® contributing editor, is the fire marshal for the University of Maryland. He is a Certified Fire Protection Specialist (CFSP), Fire Inspector II, Fire Inspector III, Fire Investigator and Hazardous Materials Specialist, and has served on state and county hazardous materials response teams. Burke is a veteran of 26 years in fire and emergency services, with experience in career and volunteer departments. He has attained the rank of lieutenant, assistant chief and deputy state fire marshal. Burke is an adjunct instructor at the National Fire Academy and the Community College of Baltimore, Catonsville Campus, and the author of the textbooks Hazardous Materials Chemistry for Emergency Responders and Counter-Terrorism for Emergency Responders. He can be reached in the Internet at [email protected].

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