4717 - Effect of Ventilation System on Particle Spatial Distribution in Ventilated Rooms PDF

Airborne particulate matter has been implicated as a major contributor to the increased incidence of respiratory disorders among people working in livestock buildings. A clear understanding of particle spatial distribution can provide important information for improvement of ventilation system design and control strategies. In this study, the dust mass spatial distributions in three different ventilation systems were measured using a multi-point sampler in a full-scale mechanically ventilated laboratory room under controlled conditions. The experimental results showed that the particle mass spatial concentrations varied widely as a result of ventilation. Increasing the ventilation rate within the same ventilation system reduced the overall mean particle concentration. At the same ventilation rate, the ventilation effectiveness varied widely with different ventilation systems. The experimental results also showed that the air outlet location had a substantial effect on the dust spatial distribution and the overall dust mass concentration. Ventilation system design was therefore shown to be critical to dust control in a mechanically ventilated airspace. Positioning the air outlet at the dustiest location can substantially improve dust removal effectiveness. The ventilation effectiveness factor was used to quantitatively describe the effectiveness of a ventilation system for removal of pollutants in a ventilated airspace.

Units: SI