Human foot tapping-induced particle resuspension in indoor environments: Flooring hardness effect

Particle resuspension due to human foot tapping (the landing phase of the foot during the gait cycle) was experimentally studied in a 25 cm (W) × 25 cm (H) × 50 (L) experimental chamber. The foot tapping was modelled using a free rotation toward the floor of a wooden rectangular plate (8 cm (W) × 22 cm (L)). Flooring included ceramic tile, hardwood, PVC tile, vinyl, and two different linoleum samples were utilized. Particle resuspension source strengths were estimated using the mass balance equation. Source strength (emission rates in number of particles per time) ranged from 4 particles/s to 0.05 particles/s. For 0.5–0.65 µm particles, the source strengths in the case of the ceramic tile are 2.5 times greater than those of the PVC tile and eight times greater than those of linoleum flooring. The results show that particles source strengths increase with flooring hardness. However, flooring roughness shows no significant influence on particle resuspension.