Particle loadings and resuspension related to floor coverings in chamber and in occupied school environments

Abstract

A series of experiments were conducted to evaluate characteristics of varied flooring types which may influence dirt buildup and airborne particle levels. The experiments included investigation of typical dirt loadings found on flooring in school environments, the time necessary to effectively vacuum dirt from textile flooring (both in chamber and school conditions), and the resuspension of particles generated from walking activity on various flooring types in chamber and classroom environments. The flooring types studied included textile floored surfaces (flow through (FT) carpet and variable cushion tufted textile (VCTT) floorings) and hard surface (vinyl composition tile (VCT)).The study demonstrates that dirt buildup on textile floors will vary based on the location within the classroom. One of the primary findings of the study is that textile floor covering in schools is not a homogeneous medium. Physical characteristics vary based on the type of backing, carpet tufted type, face weight, gauge (including stitches/inch), and adhesive requirements. This variance in physical parameters contributes to significant differences in the resuspension rates (RRs) of particles into the air, generated by walking activity. FT carpet displayed significantly greater (2.5–5 times) RRs than VCTT in both chamber conditions and classroom environments at similar floor loadings and particle size ranges. Controlled chamber test runs revealed VCT flooring exhibiting 3.6 time higher RRs than FT flooring and 12.8 time greater RRs than VCTT flooring. Moreover, particle RRs and airborne concentrations are also a function of time of walking activity, floor dust loadings and particle size ranges.