Effectiveness of Transparent Shields in Protecting Explosive Operations Personnel
Abstract
The effectiveness of relatively portable, transparent shields for protecting personnel was evaluated for the unintentional reaction of explosives, propellants, and pyrotechnics in a laboratory setting. Measurements of blast overpressure, heat flux, and temperature were made at the head positions of a sitting operator, a standing operator, and a standing observer with the energetic materials placed at a comfortable position for hands-on operations on the other side of the shield. High-speed and video photography showed shield deflection from blast and the position of the most intense heat from detonating and burning energetic materials. After each test the shield was photographed and evaluated for fragment penetration, charring, and structural damage. Up to 11.7 g of explosive was detonated to simulate the probable event when handling primary explosives and the maximum event that could occur when handling secondary explosives. An explosive powder, a pyrotechnic, and a composite propellant (up to 244 g) were ignited and burned to simulate many of the incidents that could occur when handling unconfined energetic materials, except for primary explosives. The propelling charge in a 12-gauge shotshell, containing an 8 g cylinder of explosive instead of lead shot, was ignited with the shell confined in a simulated loading press. A flat, 20" wide sheet of polycarbonate (PC) with cutouts for arms and a commercial shield for chemistry laboratories were effective in protecting against blast overpressures not exceeding 2.3 psi from detonating charges is less than or equal to 2 g. Since the blast wave reaching the operator comes around the shield, extending the sides of a flat shield away from the charge location, increasing the shield height to above the operator's head, and adding a top over the operator's head reduced the blast overpressures by a factor of three.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1994
- Accession Number
- ADA500321
Entities
People
- Harold W. Sandusky
- Verence D. Moore
Organizations
- Naval Surface Warfare Center Indian Head Division