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Relationship between the concentrations of PM2.5 indoors obtained by using the optical and gravimetric methods: preliminary analysis

Pastuszka Józef S.

Architecture Civil Engineering Environment

2020

Vol. 13, no. 4

105--113

The paper presents preliminary analysis of measurements of the mass concentrations of PM2.5 in the indoor environment, obtained with the use of two optical instruments: (Grimm device and low-cost sensor) and a sampler based on the gravimetric method (SKC). It was found that the measurement of PM2.5 using an optical device with active sampling underestimates the actual mass concentration of this mode (PM2.5), while measurement using an optical device with passive sampling of air overestimates the concentration of PM2.5. It has been shown that the physical relationship between the mass concentrations of airborne particles obtained with an optical sensor (Csensor) and concentrations obtained with the gravimetric method (Cgrav) is not linear. However, for practical reasons, the correct (“true”) concentration levels of PM2.5 in an indoor environment can be estimated by converting sensor data according to a simple linear equation, i.e., Cgrav = a Csensor. The coefficient a for the sensor used was estimated at 0.45.

Laboratory investigations applied to wood dust emmited by electrical hand-held belt sander

Dado M., Mikušová L., Hnilica R.

Management Systems in Production Engineering

2018

nr 3 (26)

133--136

Aim of this paper was to investigate the effects of grit size and wood species on mass concentration and size distribution of wood dust produced by hand-held belt sander. Experimental study was designed as 2x2 full factorial experiments. Experimental parameters and their levels were abrasive grain size (P80, P120) and wood species (European beech (Fagus sylvatica L.), Norway spruce (Picea abies)).The mass concentration of emitted wood dust was measured using aerosol monitor (TSI Inc., DustTrak DRX 8533). Sampler head was sited in place representing breathing zone of operator of sander. The results was analysed employing the analysis of variance (ANOVA) with 5% of significance level. Real-time measurements demonstrated that spruce wood generated higher dust concentrations than beech wood due to difference in abrasion durability. Compared to sanding belt with P80 grit size, approximately 16%-32% higher dust concentration was generated when the sanding belt with P120 grit size was used.