Determination of solvents permeating through chemical protective clothing with a microsensor array

The performance of a novel prototype instrument in determining solvents and solvent mixtures permeating through samples of chemical protective clothin g (CPC) materials was evaluated. The instrument contains a mini-preconcentr ator and an array of three polymer-coated surface-acoustic-wave (SAW) micro sensors whose collective response patterns are used to discriminate among m ultiple permeants. Permeation tests were performed with a 2.54 cm diameter test cell in an open-loop configuration on samples of common glove material s challenged with four individual solvents, three binary mixtures, and two ternary mixtures. Breakthrough times, defined as the times required for the permeation rate to reach a value of 1 mu g cm(-2) min(-1), determined by t he instrument were within 3 min of those determined in parallel by manual s ampling and gas chromatographic analysis. Permeating solvents were recogniz ed (identified) from their response patterns in 59 out of 64 measurements ( 92%) and their vapor concentrations were quantified to an accuracy of +/-31 % (typically +/-10%). These results demonstrate the potential for such inst rumentation to provide semi-automated field or bench-top screening of CPC p ermeation resistance.