Attack-Initiated Smoke System

Sandia National Laboratories has developed and characterized a new smoke material for access delay applications. Existing activated obscurant systems require complex command and control systems and a human to evaluate an alarm and activate the obscurant dispensing equipment. The newly developed smoke system is totally passive, requiring no maintenance or command and control system. The smoke system was designed to augment the delay features of structural barriers. It is packaged in a modular form, i.e., phenolic tubes, for easy installation into new structural barriers or it can be assembled into panels for upgrading the delay performance of existing barriers and high security doors. The smoke is initiated by a high-energy attack on the barrier. A highenergy attack is defined as one involving the use of thermal tools, aggressive cutting tools such as a demolition saw, or explosives. We refer to the obscurant system as Attack Initiated Smoke (AIS) system. The smoke provides not only a visual obscurant but also a thermal barrier at the point of attack, where it is most effective. The passive smoke system can be tailored to provide very large quantities of smoke for short periods of time, i.e., several minutes, or it can be assembled to provide tens of minutes of smoke production at a lower rate. The smoke formulation contains ammonium perchlorate and zinc powder with a polymer binder. The material is very efficient, producing 50% of its weight as aerosolized particulate. The smoke particulate is composed of zinc chloride, zinc oxide, and carbon and has toxicological properties similar to Hexachloroethane based (HC) smokes; however, processing hazards associated with the preparation of the smoke mixture are significantly less. Since the material is castable liquid (which cures to a rubbery solid) rather than a dry powder, complex geometries are simple to produce. The preferred location for the application of this new smoke system is at facility entry points or as exterior structural reinforcement. A commercial supplier is in the process of being qualified to produce the smoke material.