A circularly curved piece of LX-17 of square cross section was detonated at one end with a plane-wave lens. Detonation velocities along the inner and outer edge were measured with pins and a streak camera measured the detonation front curvature on the end face. A steady state``shadow'' or inner curve velocity of 7.13 mmyms was measured for rib radii of 89 mm and 114 mm. Time constants for the change to steady state on the curve were derived. The outer time constant is set by the time for the energy to¯ow across the explosive, not by the reaction zone length, and this results in a considerable tilt of the front. The tilt causes the leading point of the front to move far inward, close to the inner edge. A simple theory for reaction zone lengths is used ®rst on slabs and then on the rib. Because the tilt directs the front away from the inner edge, the inner edge of the rib can sustain a shadow velocity lower than the failure velocity of the cylinder or slab. The rib has been modeled with Ignition and Growth in DYNA2D, producing a smooth set of detonation velocities that are slightly low. The production betayprogram burn package in VHEMP produces a less smooth set of velocities that are too high.

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The purpose of this work is to examine the environmental, safety, health and operational aspects of detonating a confined explosive test apparatus that has been designed to maximize the dynamics of impact on beryllium metal components for Contained Firing Facility (CFF) applications. A combination of experimental collection and evaluation methods were designed and implemented to provide an evaluation of immediately postdetonation by-products reflecting a potential worst-case scenario beryllium aerosolization explosive event. The collective Material Evaluation Test Series (METS) 04 -06 provided explosive devices designed to scale for the dedicated METS firing tank that would provide a post-detonation internal environment comparable to the CFF. The experimental results provided appropriate information to develop operational parameters to be considered for conducting full-scale beryllium-containing experimental tests with similar designs within CFF and B801A. These operational procedures include the inclusion of chelating agents in pre-shot CFF cardboard containers with a minimum of 600 gallons content, an extended time period post-test before purging the CFF chamber, and an adaptation of approaches toward applications of the scrubber and HEPA systems during the post-shot sequence for an integrated environmental, safety, and health approach. In addition, re-entry and film retrieval procedures will be adapted, in line with abatement techniques for cleaning the chamber, that will be required for work inside a CFF that will contain an elevated concentration of spherical and highly aerosolizable beryllium particulate.