Simultaneous measurement of nitrous acid, nitric acid, and nitrogen dioxide by means of a novel multipollutant diffusive sampler in libraries and archives

Results: The ratios between indoor and outdoor concentrations of NO2 showed a greater penetration of pollutants indoors in the naturally ventilated library than in the filtrated archives. The indoor concentrations of HNO3 were very low probably due to the high deposition velocity of nitric acid on available surfaces. HONO concentration values were usually lower outdoors, which indicated that HONO was produced by reactions on indoor surfaces.

Introduction: A novel multipollutant diffusive sampler for HONO, HNO3, and NO2 was used and tested at four different libraries/archives in different seasons. Two were located in Switzerland in Bern (Swiss National Library) and Geneve (Bibliotheque de Geneve), both with HVAC system equipped with filters for pollutants removal, and the other two in the Czech Republic in Teplice (Regional Library) and in Prague (National Archives), where in this case the former is naturally ventilated and whereas the latter is equipped with HVAC system with filtration.