Comparative Analysis of Indoor Levels of Suspended Particulates and Nitrogen Dioxide a Few Hours later after an Asthmatic Attack

Suspended particulates （TSP） and nitrogen dioxide （NO2） are known respiratory irritants linked to asthma aggravation. This pilot study was designed to investigate the role of these pollutants on the frequency of asthmatic attack on two of the inhabitants of a household. The surveillance of TSP and NO2 in this household commenced a few hours later, after one of the occupants suffered an attack. The TSP load determination was done using a High Volume Gravimetric sampler and a light scattering method via a Haz-Dust 10 μm particulate monitor. Palmes Diffusion tubes for NO2 and a portable Crowcon Gasman toxic gas detector were utilized for NO2 screening. In the first day of monitoring in the living room, the in situ particulate sampler （Haz-Dust） recorded a mean TSP level of 26,000 μg·m^-3. A confirmatory test with the eight hour average Gravimetric sampler gave 25,833 μg·m^-3. With the use of the Gasman toxic gas detector for NO2, the NO2 concentration for the first few hours of sampling was lower than 188 μg·m^-3, the detection limit of this instrument. However, the exact NO2 concentrations for the 7 day monitoring after the attack were 27.50 μg·m^-3 （kitchen） and 12.03 μg·m^-3 （living room） as recorded by the Palmes diffusion tubes.