Task specific assessment of particle exposure and low-cost sensor performance in indoor construction environments

In this study, a workplace measurement campaign was conducted during indoor renovation of two apartments following panel removal, wallpaper removal (dry/wet), sweeping (dry/wet), and floor removal (including insulation) tasks. Measurements with a low-cost sensor (LCS; OPC-N3; Alphasense) was compared to a benchmark optical particle sizer (OPS, TSI Model 3330) to assess the applicability of this LCS in a construction worker environment. Additionally, ultrafine particle concentrations (<0.1 μm) were measured using a mobility particle sizer (NanoScan, TSI Model 3091) and a diffusion size classifier (DiSCmini).
The highest particle number concentrations (PNC) were found during floor removal, dry sweeping, and wallpaper removal, where 63 % of particles were ultrafine (<0.1 μm) and 96 % were smaller than 2.5 μm (PM2.5). The PM10 (particulate matter with a diameter <10 μm) concentrations measured during some tasks exceeded the occupational exposure limit of 10 mg m−3 for total dust with values from 0.3 to 11 mg m−3. Analytical electron microscopy analysis revealed exposure to compounds such as talc, titania, quartz, and potential asbestos. Water-based dust control methods reduced PNC by at least 84 %, highlighting their effectiveness in mitigating exposure. LCS generally underestimated particle concentrations, particularly for PM1, which was underestimated ranging from 31 % to 92 %. The largest discrepancies occurred during high concentrations in the presence of ultrafine particles, such as floor removal and dry wallpaper removal. This study also emphasizes the importance of multi-metric measurements and breathing zone assessments to accurately evaluate worker exposure and improve occupational safety.