Determination of ultrafine particle number emission factors from building materials in standardized conditions.

This article focuses on a novel methodological approach to assess ultra-fine particle (UFP) emissions from construction materials under controlled occupational exposure conditions. Using a steady-state inhalable mass concentration set at the Swiss occupational exposure limit (OEL) of 10 mg/m³ for biopersistent granular particles, the study compares particle emissions from aerogel-containing mortars, aerogel-glass-wool insulation, bulk mortar, and concrete during sawing or handling activities. Results indicate that incorporating silica aerogel into mortar does not significantly change the UFP emission profile compared to bulk mortar, while concrete sawing and aerogel-glass-wool handling produce substantially higher UFP emission factors. The proposed experimental setup provides standardized UFP emission factors that link particle number emissions to occupational exposure limits, offering a reproducible framework for evaluating inhalation exposure risks in construction environments.