Homemade Explosives: Current and Emerging Threats

August Vernon details a variety of homemade explosives that pose a serious threat to responding firefighters and other emergency workers.


Homemade explosives typically are made by combining an oxidizer with a fuel. Many of these materials are simple to make, requiring little technical expertise or specialized equipment. Instructions on how to make homemade explosives are available from many sources, but the recipes are often inaccurate and dangerous to follow. Even accurate recipes are extremely dangerous to follow and the explosives created often are highly unstable. More than one would-be bomb maker has been killed or injured while working with these materials.

Recipes for making nitroglycerin, mercury fulminate, blasting gelatin, dynamite, TNT, tetryl, picric acid, black powder and smokeless powder are found online and in printed sources. Picric acid, nitrogen trichloride and nitrogen tri-iodide are not marketed as commercial explosives, but are used in laboratories and other industrial settings. They are potentially very unstable and could be used for criminal purposes and terrorist purposes.

The purpose of the article is to provide easy-to-follow guidelines for emergency responders and incident commanders to assist in planning and training for incidents involving improvised explosive devices (IEDs). These guidelines and procedures should not replace common sense and experience. It is impossible to plan for every situation that may occur. New “best practices” and lessons learned become available on an ongoing basis, so these plans should be updated regularly. IEDs can consist of anything from homemade pipe bombs to sophisticated military ordnance; however, emergency responders are more likely to encounter IEDs and homemade explosives than military weapons in day-to-day responses.

 

Peroxide-Based

Explosives

Peroxide-based explosives such as triacetonetriperoxide (TATP), hexamethylene triperoxide diamine (HMTD) and methyl ethyl ketone peroxide (MEKP) are a growing concern. Individuals with little or no chemistry background can attempt to produce these materials. TATP has been used by terrorists in the Middle East to produce devices for suicide bombers’ belts and was used in terrorist attacks elsewhere, including the 2005 mass-transit bombings in London, England. TATP has been produced in the United States by terrorists, criminals, lone offenders and hobbyists.

Peroxide-based explosives are made by mixing concentrated hydrogen peroxide (an oxidizer) with a fuel such as acetone or ethanol along with a strong acid. Different recipes vary the fuel and concentration of peroxide to create a range of explosives. TATP and HMTD are dangerous to make and handle because they are very unstable. Both can be made in illicit laboratories located almost anywhere, since highly specialized equipment is not needed for the manufacturing process. TATP is typically found in crystal form while HMTD is usually a powder; however, peroxide explosives can be liquids as well.

 

Ammonia Nitrate/Fuel Oil

It is relatively easy to produce ammonium nitrate/fuel oil (ANFO) by obtaining the ingredients or by improvising them. Ammonium nitrate (AN) and fuel oil are widely accessible and relatively inexpensive, and neither is classified as an explosive. AN is sold at farming supply stores and its widespread availability makes it a likely target for theft or purchase by criminals and terrorists. The same is true of the AN precursors ammonium hydroxide and nitric acid.

Fuel oil number 2, or diesel fuel, is the most popular fuel oil used in the synthesis of ANFO. Diesel and other fuels are available at gas stations, heating and appliance stores, hardware stores, farming supply stores and outlets that sell gas- or diesel-powered boats. Other common fuels such as nitro-methane and aluminum powder can be used. ANFO was used during the 1995 terrorist attack on the Murrah Federal Building in Oklahoma City, OK, and the 2011 terrorist attack with a vehicle-borne improvised explosive device (VBIED) in Oslo, Norway.

 

Explosives Labs

This content continues onto the next page...