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Chemical warfare agents are deadly toxic and their even one gram quantity can kill around hundreds of soldiers. Such chemicals are potential threats, for civil population, if used by terrorists, as these toxic agents are colorless, odorless, highly vaporizable, and can be dispersed easily in air. For protection, detection of such chemical vapours at extremely low concentration (Sub PPM Level) is necessary. DRDE, Gwalior is a pioneer DRDO Lab, doing R & D for chemical detection and protection, against chemical warfare Agents, and has developed a large number of technologies, for detection as well as 1 protection from CWA threats. Quartz Micromass Balance (QMB) works on the principle of piezo electric effect. A differential quartz crystal oscillator made from Quartz crystal, coated with chemically active interface, provides a reversible, and rapid detection signal for sub PPM level concentration of toxic chemical agent Sarin and its simulant DMMP. Quartz Micromass Balance sensors are quite sensitive and rapid. The science associated with such a sensor , its functional and design aspect and representative practical results are being described. DRDE, Gwalior has developed a large number of technologies for NBC protection of the armed forces from a NBC (Nuclear, Biological and Chemical) attack. For protection, Face mask Canisters, based on active charcoal filtering have been made, which can absorb toxic chemicals, biological bacteria, & spores, radioactive dust particles etc and provide breathable air in a toxic chemical environment. Such filtering canisters and high volume filers are in use of Indian forces for civil preparedness.

The dark conduction current in 100 μm thick pure and anthracene doped bimetallized poly(methyl methacrylate) (PMMA) foils was measured at temperatures ranging from 333 to 383 K and filds ranging from 8 to 50 kV/cm. An attempt was made to identify the nature of the current by comparing its observed dependence on electric field, temperature and dopant concentration with the respective characteristic features of the existing theories of electrical conduction. The observed characteristics suggest that the charge carriers are generated by field assisted lowering of coulombic barriers at the traps and are conducted through the bulk of the material by a hopping process between the localized states by a Jonscher–Ansari modified Poole–Frenkel mechanism. The high value of the activation energy is considered to indicate the possibility of charge carrier species inside the polymer bulk being ionic in nature.

The charge storage and transport behaviour of 100 /spl mu/m thick pure and 0.1 wt% anthracene doped poly(methyl methacrylate) (PMMA) foils has been investigated by absorption current, isothermal surface charge decay and thermally stimulated discharge current (TSDC) measurement techniques over a temperature range of 298 to 393 K, with fields ranging from 8 to 50 kV/cm.

The charge storage and transport behaviour of bimetallized, 100 /spl mu/m thick, pure and anthracene doped poly methyl methacrylate (PMMA) foils has been studied by investigating dark conduction currents, transient absorption currents and thermally stimulated depolarization (TSD) over a wide temperature range of 298 to 393 K, with fields ranging from 8 to 50 kV/cm.