Characterization of Explosives & Precursors

Download Project Report (Phase 2, Year 7)

Project Description

Project R1-A1 seeks to determine the physical properties, synthesis, and destruction mechanisms of improvised explosives, often called homemade explosives (HMEs). The overall objective of this project is to make the detection, handling, and transport of these materials by the Homeland Security Enterprise (HSE) as safe as possible, while obstructing the manufacturing of HMEs by terrorists. Additionally, the signatures of HMEs must be accurately characterized to allow for reliable detection. In the case of explosives, complete characterization is a matter of safety as well as performance. Most HMEs are not new, many having been reported in the late 1800s; however, “routine” handling of these explosives and resulting accidents by those involved in the homeland security enterprise (HSE) requires a thorough understanding of their properties.

To detect, destroy, handle safely, or prevent the synthesis of HMEs, complete understanding of the following aspects is required:

  • How an HME is formed and what accelerates or retards that formation;
  • How it decomposes and what accelerates or retards that decomposition;
  • How it crystallizes;
  • What is its vapor pressure and its headspace signature;
  • What is its density;
  • What is its sensitivity to accidental ignition as well as purposeful ignition; and
  • What is its performance under shock and fire conditions?

Characterization of HMEs is an ongoing research effort at the Department of Homeland Security (DHS) including vendors and associated researchers—it affects the entire HSE. In many cases, our methods of analysis have lead the way for other members of the HSE. Our studies on the extreme sensitivity of HMTD to moisture and acidity may have prevented mishandling in a number of laboratories. Many vendors of explosive detection instrumentation have asked for our help in working with materials characterized in this project, or requested access to the explosives database we have developed. Currently, the explosives database is subscribed to by over 1000 people, including members of DHS, and other government agencies.

Given the large scale of this mission, we have chosen areas considered most urgent or reachable by our present experience and instrument capabilities. Having examined triacetone triperoxide (TATP) in detail, Project R1-A.1 is now examining hexamethylene triperoxide diamine (HMTD), erythritol tetranitrate (ETN), and other nitrated sugars and fuel/oxidizer (FOX) mixtures.


Over the years, this project has resulted in well over a dozen papers on HMEs, such as TATP, HMTD, ETN, and other nitrated sugars. This will be a lasting achievement for DHS, as well as the database compendium.
Year 4 Annual Report
Project Leader
  • Jimmie Oxley
    University of Rhode Island

Faculty and Staff Currently Involved in Project
  • Gerald Kagan
    University of Rhode Island

Students Currently Involved in Project
  • Taylor Busby
    University of Rhode Island