“Good point. Flammable liquids or gases are usually not used as the primary charge/ explosive device in Improvised Explosive Devices (IED). However, they are used to intensify the destructive nature. For example, when Iraqi insurgents were utilizing the IED on an everyday basis, they would place propane tanks and/or jugs of gasoline around the IED. So let's say the insurgents had two 155 mm artillery rounds rigged as the IED, they would also place the propane tanks right next to it to create a more intense fireball, thus increasing the effects.”Typically IEDs are small so that they can be concealed to prevent detection; this would preclude the use of flammable liquids or gasses as the primary charge because of the volume necessary to form the vapor cloud necessary for an explosion as opposed to a fire. The type IED I was describing utilizes large volumes of flammable liquids like gasoline. To get a VCE that liquid must be discharged into a large semi-enclosed volume that allows for the formation of a vapor cloud. While the Army’s work in the seventies concentrated on employing the gasoline in a sewer system for large scale excavations, the same thing could be done by pumping the fuel into a large building like a shopping mall, church or sports arena. Gasoline Terminals as Targets From the blog on the revised DHS notice, Anonymous wrote, in part:
“In addition to what you wrote for Gasoline security comments, I would contribute the fact that these above ground storage tanks are "visible" targets for terrorists to strike at. If I had to put a terrorist's hat on, I'd say why not strike it if it is there and it will make news.”Combine this with the fact that most of these facilities have little more apparent security than a fence and a locked gate and they appear to be easy targets to hit. Now, I haven’t taken a comprehensive survey of gasoline terminals across the country, but two of the three that I have driven past often don’t even have gate guards. One other point while I’m thinking about it, many of these terminals sit atop a gasoline pipeline. A successful attack on the terminal (successful defined as effecting a VCE) will certainly damage the pipeline; at least enough to interfere with deliveries for a while. How long before that interruption begins to have economic impacts in the service area of that pipeline?