Birch and grass pollen grains as well as pollen-derived small particles appear as potent allergens in the outdoor air during spring and summer. The occurrence of pollen allergens in indoor air, however, has not been studied in depth due to lack of suitable sampling and analytical methods. Herein; a recently reported "direct on sampling filter estimation" (DOSAFE) technique (Acevedo et al., 1998) has been validated for quantification of pollen allergens in indoor air using two school rooms and two office rooms as experimental models.
Various studies on indoor and outdoor particulate matter in the urban environment in the vicinity of busy arterial roads in the centre of the subtropical city of Brisbane have indicated that the revised United States Environmental Protection Agency National Ambient Air Quality Standards (US EPA NAAQS) for P articulate matter PM2.5 could be exceeded not only outdoors but also indoors.
Particle characteristics in indoor environments are strongly related to the characteristics ofoutdoor particles. The aim of this work was to investigate how submicrometre particle numberconcentration changes with the distance from a road.
The cabin air filter performance is of prime importance for the air quality in vehicles. New clean filters were tested but also filters loaded with actual traffic contaminants. Both laboratory and field measurements were included in the study. Direct reading instruments and filter sampling was used for the loading rate determinations. The filter performance includes particle filtration efficiency with regards to particle size, filter loading and flow rate as well as filter pressure drop related to filter loading. Test results for these paramenters are presented.
Indoor and outdoor particle concentrations and ventilation rates were measured versus time ina large office building without tobacco smoking. Periodically, high efficiency filters replacedthe normal filters in air handling systems. For all particle sizes, indoor concentrations variedconsiderably with time. Even with the normal air filters, which have a low efficiency forsubmicron particles, number concentrations of submicron particles were a factor of three tosix smaller indoors compared to outdoors.
The fractional collection efficiency (FCE) tests of a commercially available two-stageelectrostatic precipitator (ESP) have been performed for six flow rates. The tests covered theparticle size range from 0.018-1.2micrometer using two types of test aerosols, NaCl andenvironmental tobacco smoke (ETS). Measurements were performed by means of twoScanning Mobility Particle Sizers (SMPS) and the Aerodynamic Particle Sizer (APS).
Particle deposition from turbulent duct flow is modelled and related to particle penetration of a ventilation system for a commercial office building. Three published turbulent deposition models capable of accommodating surface roughness are compared to experimental data and used to determine the penetration of 0.1 - 10 (m spherical particles through a sample duct run. Depending on the model employed, penetration fractions varied from 0.40-0.94 for 0.1 (m particles and 0.28-0.73 for 10 (m particles.
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