2012 Emergency Response Guidebook

By Stephen L. Hermann, CEM

The Emergency Response Guidebook (ERG) for hazardous materials, jointly developed by the U.S. Department of Transportation (DOT), Transport Canada, and the Secretariat of Communications and Transportation of Mexico (SCT), is intended to be placed in each emergency service vehicle nationwide. Updated and reissued each four years, the latest edition, ERG2012, updates the 2008 edition. The next edition will appear in 2016. It is available in on-line editions in English and Spanish.



            Although ERG2012 has no major changes from the 2008 edition (ERG2008), there are several useful new sections and hundreds of revisions to initial isolation and protective action distances. The guidebook cover has been updated. In the ERG2012, the following items have been expanded or revised from the ERG2008:


General Information

▪ Several sections, such as the Glossary and the User Guide, have been moved to the back of the book (white pages).

▪ All new dangerous goods listed in “UN Recommendations on the Transport of Dangerous Goods” have been added. They are listed numerically according to ID number in the yellow-bordered pages and in alphabetical order in the blue-bordered pages.

▪ The following components have been expanded or revised:

  Shipping Documents (Papers)

  How to Use this Guidebook During an Incident

  User’s Guide

  Isolation and Evacuation Distances

  Who to Call for Assistance

  Table of Placards and Initial Response Guide to Use On-Scene

  Rail Car Identification Chart

  Road Trailer Identification Chart

  Fire and Spill Control

  Pipeline Safety Information (two new pages)

  Criminal/Terrorist Use of Chemical/Biological/Radiological Agents


  Publication Data (and related information)

  Emergency Response Telephone Numbers


▪ Safety Recommendations/Emergency Response Guides (orange-bordered pages)

  Some Guides have been “tuned up.”

 ▪ “Table of Initial Isolation and Protective Action Distances” and the “Table of Water-Reactive

 ▪ Materials Which Produce Toxic Gases” (Green-bordered pages):        

 ▪ Added Table 3 for six gases which are toxic by inhalation.

 ▪ Tuned-up “Initial Isolation & Protective Action Distances.”

 ▪ “Fire and Spill Control” Section. Added a “Boiling-Liquid, Expanding-Vapor Explosion (BLEVE) 


▪ “Criminal/Terrorist” Section: Added an “Improvised Explosive Device (IED) Safe Standoff Distances




The ERG2012 retains the following features introduced in previous DOT guides:

            ▪ Recommended distances are in metric and English units.

            ▪ The term “dangerous goods” is synonymous with “hazardous materials.”

            ▪ The term “toxic” is synonymous with “poison” and “poisonous.”

            ▪ Includes a two-page guide on how to respond.

            ▪ The suffix “P” added to guide numbers indicates a polymerization hazard.

            ▪ Each Guide shows the broad types of materials covered.

            ▪ The term “evacuation distance” is replaced by “protective action distance,”

               and there is an explanation of “in-place protection.” 

            ▪ Table 1 – “Initial Isolation and Protective Action Distances” pages are bordered in

              green for quick access.

            ▪ Contains simple, easy-to-understand advice.


The book retains its strongest asset—the use of vital, nontechnical, easy-to-follow information in a brief, practical form. The guide’s initial white pages contain reference and usage information, definitions, and general guidance, including examples of shipping papers, markings, and placards. Information on explosives directs users to Guide 112 (orange-bordered pages) for all explosives except for explosives 1.4 (explosives C) and explosives 1.6 (extremely insensitive articles), for which they are directed to Guide 114. If no specific chemical information is available, turn to Guide 111 and use it until additional information is available.

Page 2 offers the following “Safety Precautions,” which are explained in detail:

1. Approach cautiously from upwind, uphill, or upstream.

2. Secure the scene.

3. Identify the hazards.

4. Assess the situation.

5. Obtain help.

6. Respond.

7. Above all (i.e., cautions).

On page 4, the DOT hazard class and division numbers are shown with corresponding hazard class names: e.g., “Class 2 - Gases,” “Division 2.1 – Flammable Gases.”  Many trucking companies use the international hazardous materials placards that do not use the hazard class names but use numbers instead.

One of the most valuable features of ERG2012 remains the “Table 1 - Initial Isolation and Protective Action Distances,” starting on page 292. The preceding introduction starts on page 285 and covers protective action decision factors, protective actions, background on the table, and directions for using it. Table 1 covers those chemicals that are toxic or poisonous by inhalation, and gives suggested initial isolation distances at the scene. It then recommends “Protective Action Distances,” which could involve either evacuation or “protection in place,” recognizing that most business buildings or homes can provide air that is cleaner than that which evacuees might encounter in trying to leave an area of a toxic chemical cloud.

Substances are indexed in the yellow- and blue-bordered pages. Both indexes direct you to the appropriate orange-bordered guide page, which gives the appropriate dos and don’ts.

As noted above, in the yellow-bordered pages, substances are listed in numerical order according to the four-digit identification number assigned by the United Nations or a North American committee (UN or NA prefix.) The blue-bordered pages alphabetically list chemicals and, again, refer you to the proper orange-bordered page guide page for emergency response information.  Entries highlighted in green in the yellow or blue indexes indicate the chemicals that are poisonous when inhaled; the user is referred to the green-bordered pages, which includes Table 1, “Initial Isolation and Protective Action Distances.”

The orange-bordered page Guides are divided into “Potential Hazards,” “Public Safety,” and “Emergency Response” sections.

“Potential Hazards” explains the possible hazards involved with the material and covers “Fire or Explosion,” “Risk,” and “Health,” which covers the substance’s physical and toxicological hazards.     

“Public Safety” gives guidance on general and evacuation information for the protection of the public and protective clothing advice.

“Emergency Response” is divided into three sections dealing with action planning data. “Fire” indicates recommended fire suppression and control actions, “Spill or Leak” addresses recommended actions for spills, and “First Aid” offers health action advice.

The green-bordered Table 1, “Initial Isolation and Protective Action Distances” pages contain the recommended minimum distances people should maintain away from spills of hazardous materials that produce poisonous effects when inhaled. The distances shown are for the first 30 minutes of the incident; they could increase after that time.

The two areas of concern are the Initial Isolation Zone and the Protective Action Zone. The Initial Isolation Zone is the area surrounding the incident where persons may be exposed to dangerous and life-threatening concentrations of materials. The Protective Action Zone is where downwind persons may become incapacitated and unable to take protective action or may suffer serious or irreversible health effects. In the orange-bordered Guides under “Potential Hazards,” fragmentation hazards are clearly indicated. The public may be endangered for downwind distances of up to 11+ km (7+ miles). This is a square where the downwind width is the same as its length.

Hundreds of these distances have been revised. For example, on the first of 52 green-bordered pages, are listed 18 chemicals with 38 changes to recommended distances; 12 have been increased, and 26 have been decreased.  In some cases, distances have been cut in half, as in cyanogen and cyanogen gas, where the day protective action distance for a small spill has decreased from 0.2 to 0.1 km and from 3.5 km to 1.7 km for a night large spill.

Chemical warfare agents are listed alphabetically in the blue-bordered pages according to their common names--e.g., tabun, sarin, and soman--and their common abbreviations (GA, GB, and VX, etc.)

The four pages on chemical, biological, and radiological agents were developed by the Department of National Defence (Canada), the U.S. Department of the Army Aberdeen Proving Ground, and the Federal Bureau of Investigation. They discuss the following:

Differences between chemical, biological and radiological agents,

Indicators of a possible chemical incident,

Indicators of a possible biological incident,

Indicators of a possible radiological incident, and

Personal safety considerations.

In the United States, first responders must be trained in how to use of this guidebook, according to the requirements on the U.S. Department of Labor’s Occupational Safety & Health Administration (OSHA, 29 CFR 1910.120) and regulations issued by the U.S. Environmental Protection Agency (EPA, 40 CFR Part 311). Emergency service organizations that have not yet received copies of ERG2012 should contact the respective state distribution center in their country, state, or province.  In the United States, information about the distribution center for your location may be obtained from the Office of Hazardous Materials Safety Web site at http://hazmat.dot.gov. The Web site also offers a free, full PDF file copy of ERG2012 in English and Spanish.


The DOT ERG2012 is the most widely used reference source for hazardous materials emergencies in the country; more than 11 million copies have been distributed free to date. Your emergency service vehicle should contain a copy of this book, which has become one of the most popular publications ever printed by the U.S. Government.


Stephen L. Hermann, CEM, retired as the hazardous materials coordinator for the Arizona Department of Public Safety and as Arizona’s senior state on-scene coordinator for hazardous materials emergency response. He is also a retired U.S. Army Reserve Chemical Corps colonel. He has supervised more than 200 serious hazardous materials highway and rail incidents over the past 25 years. Hermann has a bachelor of science degree in explosives technology from the University of Minnesota and is a graduate of the U.S. Naval School Explosive Ordnance Disposal, United States Army Command and General Staff College, and the U.S. Army War College. He teaches hazardous materials courses around the country.


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