INFRARED EVANESCENT ABSORPTION-SPECTROSCOPY OF TOXIC-CHEMICALS USING CHALCOGENIDE CLASS FIBERS

We have detected hazardous and toxic chemicals such as chlorinated hyd rocarbons and benzene and its derivatives using evanescent wave spectr oscopy with in-house drawn chalcogenide glass fibers. Although, these chemicals have been readily detected down to the volume percent level, we make appropriate recommendations to lower the detection limits to the part per million level, While the current fibers can be used in le ngths of up to 30 m for detection and identification of these chemical s, our results indicate that the remote capabilities of these fibers c an be significantly improved into the several hundreds of meters range with lower loss fibers, as they become available with improved proces sing,