Air quality in the near zone of humans with different ventilation strategies

The concentration in the convection flows of resuspended particles from the floor area was experimentally investigated under laboratory conditions with different ventilation strategies. It was concluded that the number of small particles transported into the breathing zone was large with a forced resuspension; however there seemed to be little risk of resuspension of particles from the floor due to the air supply under normal conditions. The geometry of the simulators and the layout of the room had a big influence on the exposure. The particle concentration in the convection flows was much higher with displacement than with mixing ventilation indicating a higher exposure risk. In previous studies of particle exposure the concentrations are mostly presented in particle mass but here the results are presented in number concentration. As potential health problems are more closely associated with particle number or surface area than with particle mass this study can be of interest when designing a ventilation system.QC 2012020