Assessing the Damaging Potential of Non-Ideal Explosives Based Upon Ammonium Nitrate Fertilizer
Abstract
In the UK the last few years have seen five separate occasions when large vehicle borne bombs have been used by terrorists to inflict massive damage against commercial targets within city areas, some with loss of life of innocent bystanders. These devices have been constructed from large masses of fertilizer modified by grinding and the addition of a solid fuel to convert them into explosives. On April 19th 1995, a similar massive bomb this time allegedly based upon a mixture of prilled agricultural ammonium nitrate fertilizer and fuel oil (ANFO) was used in Oklahoma City to devastate the Federal building with severe loss of life. Explosives based upon fertilizer are classified as non-ideal. They neither react in the same way as ideal explosives nor does their performance scale in the same manner as ideal explosives. Previous studies on non-ideal commercial explosives such as Ammonium Nitrate/Fuel Oil (ANFO) have reported that the TNT equivalence increases as the charge size increases (Reference 1) In 1994, DERA Fort Halstead, an agency of the UK Ministry of Defence, was charged with assessing the TNT equivalence of the particular type of improvised explosive based upon modified fertilizer which was being used by the terrorists attacking UK targets. These studies were to be combined with fundamental studies into the forensic aspects of post blast effects of such large vehicle borne devices in urban environments. The TNT equivalence of the fertilizer based explosive was required primarily by specialists in the field of assessing the interaction of the explosive and structures. Most of their computer programmes required the equivalence figure for computation. Initially studies were made of these explosives at small scale with charges of 17 kg, 37 kg and 90 kg.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1996
- Accession Number
- ADA507753
Entities
People
- Maurice Marshall
- Peter J. Hubbard
Organizations
- Ministry of Defense