A Statistical Model to Predict Pesticide Penetration Through Nonwoven Chemical Protective Fabrics

The effects of the liquid/fabric surface tension difference, solid volume fraction of fabrics, fabric thickness, and viscosity of pesticide mixture on pesticide penetration of nonwoven fabrics are studied. A predictive statistical model to provide recommendations for selecting chemical protective clothing for pesticide applicators is developed to estimate pesticide penetration through and thermal comfort of nonwoven fabrics. The study involves fourteen commercial nonwovens and eleven pesticide mixtures of atrazine and pendimethalin at different concentrations. Using three mixtures that represent a range of viscosity and surface tension, percentages of pesticide penetration are measured, along with fabric thickness, weight, and air permeability. Statistical analyses help reveal the relationship between liquid/fabric parameters and pesticide penetration. Repellent finished fabrics exhibit extremely low penetration regardless of pesticide mixture or other fabric characteristics, whereas fabric type and pesticide mixture affect the barrier performance of untreated fabrics. For untreated nonwovens, statistical analyses show that pesticide penetration has the highest correlation with the surface tension difference between fabric and pesticide mixture, followed by solid volume fraction and thickness. Protection performance shows a significant negative correlation with air permeability for untreated nonwovens, indicating thermal comfort decreases with increased protection performance. The combination of fabric air permeability and thickness and solid volume fraction can be used when selecting appropriate clothing that offers needed chemical protection while maximizing thermal comfort.