No abstract

Development and refinement of laboratory tests to prescreen barrier fabrics and predict performance in the field are important, since field studies are 1) expensive and time-consuming, and 2) variables such as wind, humidity, and sunlight are impossible to control. The purpose of this study was to determine the reproducibility of the spray penetration tests to prescreen fabrics as barriers to pesticide penetration with the UNCG-Clemson spray box. Tests were made to measure the effects of two exposure times, six pressures, and four sample locations on the deposition of water sprayed on gauze samples positioned on each of four vertical arm test sites. The highest reproducibility of the UNCG-Clemson spray box was found in a spraying condition at 206.8 or 275.7 kPa and 85 seconds exposure with water (CV=4%, SD=0.0041) and 0.125% atrazine (AAtrex Nine-O®) solution.

Protective suits made of two experimental nonwoven fabrics and a woven control fabric were worn by atrazine production workers to test barrier efficiency in a field situation. The nonwoven test suits were made of a spunbonded/meltblown/spunbonded polypropylene fabric with a liquid resistant finish and a wood pulp/polyester/spunlaced fabric with a fluorocarbon finish. A woven cotton suit was used as a control. Ten outside and ten inside cotton gauze patches were attached to the suit and analyzed for atrazine residues by a gas Chromatograph. The outside patches showed significantly higher residues than the corresponding inside patches in all three suits, suggesting that the protective clothing fabrics functioned as a barrier to the paniculate contaminants of atrazine. The residues extracted from the outside patches differed significantly by job functions for all three suits. The total barrier efficiency did not differ significantly among the three suits. It is suggested that fabrics designed to be resistant to particulates should be used in exposure to powdery contaminants.