THIN FILM PERSONAL DOSIMETERS FOR DETECTING TOXIC PROPELLANTS
Abstract
The subject of this report is the development of a portable system for the detection of low concentrations of nitrogen tetroxide (N2O4), fluorine (F2), and unsymmetrical dimethylhydrazine (UDMH) in air. The detection system is based upon the change of electrical resistivity of thin metal films when exposed to these gases. Silver metal films coated with appropriate salts proved to be applicable to the detection of all three gases; however, the following sensitized metal films were found to be optimum: for N2O4, silver; for F2, copper; and for UDMH, gold. Using the best film and salt combinations found to date, N2O4 could be monitored over the range of 0.1 to 50 ppm, F2 over the range 1.0 to 50 ppm, and UDMH over the range 10 to 100 ppm, with a standard deviation of about 20 percent. The effects of temperature over the range 50 to 90C and of humidity from 10 to 90 percent on the response characteristics of the thin film sensors were found to be significant but within the tolerance limits. Means for reducing these effects were suggested which, if successful, would, in effect, make this detection system practically independent of changes in the environment. A portable breadboard readout instrument was designed and fabricated for use with the sensors to form an integrated detection system for personal protection.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1967
- Accession Number
- AD0652849
Entities
People
- C. R. Townsend
- G. A. Giarrusso
- H. P. Silverman