ABSTRACT
A pipe bomb is an improvised explosive device (IED) which consists of a pipe, an initiation mechanism, and an explosive. ›e “classical” pipe bomb is a steel pipe nipple* with threaded cast iron end caps. Plastic polyvinyl chloride (PVC) and acrylonitrile-butadiene-styrene (ABS) pipes, and copper pipes with crimped ends, are also used. Initiation of pipe bombs containing low explosives typically is achieved with ˜ame or a glowing ‡lament, whereas high explosives (except primary high explosives such as lead azide, triacetone triperoxide (TATP), etc.) require a detonator (blasting cap). Examples of low explosives are commercial black powder and its substitutes, ˜ash powder, smokeless propellant powders, and improvised explosives formed from mixtures of chemicals such as inorganic oxidizers and appropriate fuels. Examples of high explosives are emulsions, dynamite, and plastic explosives. Low explosives normally de˜agrate (burn very rapidly with a propagation velocity less than the speed of sound), whereas high explosives detonate generating a shock wave that precedes the reaction front and propagates through the unreacted material at greater than the speed of sound. Low explosives require containment to generate the gas pressure necessary for an explosion. Commercial examples include bullet cartridge cases and cardboard tubes sealed at one end, as used in ‡reworks and model rockets. High explosives do not require containment. A pipe containing a high explosive serves only as a source of fragmentation.
