Characterization, Fate, and Re-Suspension of Aerosol Particles (0.3-10 µm): The Effects of Occupancy and Carpet Use

Abstract

In this study we present the particle number size distribution (diameter 0.3-10 µm with 1-minute time resolution) inside four offices (naturally ventilated) inside two university buildings. Each office had a typical environment in terms of occupancy and furniture. We focused on the differences between workdays and weekends in terms of particle number (PN) and particle mass (PM, assuming spherical particles with unit density) concentrations. Moreover, we illustrated the effect of workers' activity (occupancy, smoking, etc.). We also applied a simple indoor aerosol model to estimate the fate (gravitational settling and exfiltration) and source strength of aerosol particles within the measured particle size range. During workdays, the highest measured 24-hour average PM 10-1 in the occupied office was 41.5 µg m -3 (PN 10-1 = 2.2 cm -3 ) compared to 9.0 µg m -3 (PN 10-1 = 1.2 cm -3 ) in the unoccupied offices. The ventilation rate of the offices that were opposite to each other was about 0.15 h -1 whereas it was 0.28-0.38 h -1 for the other offices, which were a bit distant from each other. The gravitational settling analysis suggested that a suitable particle density (ρ p ) could be ~1.7 g cm -3 with a shape factor χ ~1.57, which is similar to mineral dust particles. The gravitational settling rate of particles around 2 µm in diameter was about 0. ). This study provided us with an insight about the effect of occupancy and carpet use on the dynamic behavior (fate and resuspension) of dust particles inside university office buildings located in semi-arid regions.

Contribution of Visitors to the Indoor PM in the National Library in Prague, Czech Republic

“…This agree well with observation of Thatcher and Layton (1995), Abt et al (2000) and Hussein et al (2015a) who found that movement in the indoor environment significantly . Practically constant value for PM 0.7-10 observed during all season indicates also stable regime of visits.…”

Indoor Particle Concentrations, Size Distributions, and Exposures in Middle Eastern Microenvironments

“…Evaluation of indoor air pollution and concentrations of particulate and gaseous indoor air pollutants in Middle Eastern dwellings has been given limited attention in the literature. In Jordan, one study investigated the effects of indoor air pollutants on the health of Jordanian women [29] and three studies evaluated concentrations of indoor particles in Jordanian indoor environments [30][31][32]. These studies provided useful insights on the extent of air pollution in selected Jordanian indoor environments and the role of cultural practices on the nature of indoor emission sources.…”

Performance of New and Artificially Aged Electret Filters in Indoor Air Cleaners

“…The problem not only concerns atmospheric pollution, but also the indoor environment since people in industrial nations spend most of their time inside buildings . Indoor air can be deteriorated either by infiltration from outside, by indoor sources such as, e.g., smoking, cooking or candles or due to resuspension by cleaning or walking .…”