The influence of different shoes and different flooring materials on particle resuspension

Abstract

The resuspension of airborne particulate matters (PM) indoors causes the effect harmful to the human’s health. Such of the exposure could be induced by human activities such as walking. This work investigated the resuspension and translocation of PM from different flooring materials by human walking. In the experiment, four types of flooring materials (PVC plate, tile, shag rug and short wool rug) and five types of shoes (boots, sneaker, slipper, high heels and leather shoes) were chosen to carry out the study. The flooring materials were seeded in the chamber with solid dust (ISO 12103-1, A2 Fine Test Duct with the size range from 0.714 to 10μm, since 10μm is the upper limit of test range from the optical particle size spectrometer) through the venture vacuum generator and the pump set. After the deposition of dust, the test took place in a sealed test chamber in the laboratory. The airborne particulate matter concentration was measured by the optical particle size spectrometer (OPSS) in different height during the resuspension test.

Scanning electron microscopy (SEM) of carpet fibers was used to determine the fraction of dust available for resuspension. The data of mass concentration recorded from the OPSS and some background information from this study were used to generate the emission factors by particle size for walking with two frequencies, 84 steps per minute and 120 steps per minute on all the flooring samples. It is found that the dust loading did not affect the emission factor, indicating that the amount of resuspension PM was directly proportional to the available PM in the flooring sample. According to the study, the emission factor of shag rug was much larger than the others and the whole result taking by the leather shoes was also larger than the slippers with flatten base. The result was supported by induced velocity test.