To: Head of Fire Departments
From: Stephen D. Coan, State Fire Marshal
Date: September 10, 2003
Re: Chemical Reaction Bombs

In recent months the Hazardous Devices Unit and the Hazmat Teams of DFS have responded to incidents involving CHEMICAL REACTION BOMBS (CRBs). CRBs utilize normal chemical reactions to generate expanding gases resulting in an over-pressure detonation. These types of devices may be contained in plastic bottles or other vessels and have caused property damage and injury.

If a suspicious device of this nature is discovered, it may or may not shows signs of reaction. CRBs generally use an acid/base reaction. Signs of reaction may be a color change, visual evidence of vessel expansion and/or effervescence. In some reactions, sufficient heat MAY be generated to show a contrast with thermal imaging camera. While the presence of heat contrast is an indicator of a reaction, the absence should not be assumed to indicate that the device is inert.

The absence of rupture/detonation DOES NOT indicate an absence of danger. A 300' safety perimeter should be established around the suspected device and it should not be disturbed. A CRB under reaction may become extremely weakened and these devices have detonated simply by being handled. If a CRB is suspected contact the Hazardous Devices Unit for safe mitigation.

Household products used for CRB often include liquid drain openers, muriatic acid and aluminum foil. CRBs may contain B.B's or other objects to act as projectiles. If a CRB has detonated, chemical hazards from the products used may be present including chemical burns and inhalation hazards. Do not attempt to clean the site without testing for the presence of chemical hazards. This may require activation of a Hazardous Materials response to identify the chemicals involved.

The site of a detonated CRB is also a crime scene. Except as is necessary to manage an emergency response for casualties or to mitigate on-going hazards, the site of a CRB detonation should be preserved as a crime scene.