title: Urban Pollutant Transport and Infiltration into Buildings Using Perfluorocarbon Tracers.
abstract: People spend the majority of their time indoors and therefore the quality of indoor air is worthy of investigation; indoor air quality is affected by indoor sources of pollutants and from pollutants entering buildings from outdoors. In this study, unique perfluorocarbon tracers were released in five experiments at a 100 m and ~2 km distance from a large university building in Manchester, UK and tracer was also released inside the building to measure the amount of outdoor material penetrating into buildings and the flow of material within the building itself. Air samples of the tracer were taken in several rooms within the building, and a CO₂ tracer was used within the building to estimate air-exchange rates. Air-exchange rates were found to vary between 0.57 and 10.90 per hour. Indoor perfluorocarbon tracer concentrations were paired to outdoor tracer concentrations, and in-out ratios were found to vary between 0.01 and 3.6. The largest room with the lowest air-exchange rate exhibited elevated tracer concentrations for over 60 min after the release had finished, but generally had the lowest concentrations, the room with the highest ventilation rates had the highest concentration over 30 min, but the peak decayed more rapidly. Tracer concentrations indoors compared to outdoors imply that pollutants remain within buildings after they have cleared outside, which must be considered when evaluating human exposure to outdoor pollutants.
authors.affiliation: Atmospheric Chemistry Research Group, School of Chemistry, Cantock's Close, University of Bristol, Bristol BS8 1TS, UK. j.c.matthews@bristol.ac.uk.
authors.forename: James C
authors.initials: JC
authors.lastname: Matthews
authors.affiliation: The Centre for Atmospheric Science, The School of Earth, Atmospheric and Environmental Sciences, The University of Manchester, Simon Building, Brunswick Street, Manchester M13 9PL, UK. asan.bacak@manchester.ac.uk.
authors.forename: Asan
authors.initials: A
authors.lastname: Bacak
authors.affiliation: Atmospheric Chemistry Research Group, School of Chemistry, Cantock's Close, University of Bristol, Bristol BS8 1TS, UK. anwar.khan@bristol.ac.uk.
authors.forename: M Anwar H
authors.initials: MA
authors.lastname: Khan
authors.affiliation: Atmospheric Chemistry Research Group, School of Chemistry, Cantock's Close, University of Bristol, Bristol BS8 1TS, UK. matthew.wright@bristol.ac.uk.
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Wright
authors.affiliation: The Centre for Atmospheric Science, The School of Earth, Atmospheric and Environmental Sciences, The University of Manchester, Simon Building, Brunswick Street, Manchester M13 9PL, UK. michael.priestley@manchester.ac.uk.
authors.forename: Michael
authors.initials: M
authors.lastname: Priestley
authors.affiliation: Atmospheric Chemistry Research Group, School of Chemistry, Cantock's Close, University of Bristol, Bristol BS8 1TS, UK. d.martin@bristol.ac.uk.
authors.forename: Damien
authors.initials: D
authors.lastname: Martin
authors.affiliation: NASA/Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA. carl.j.percival@jpl.nasa.gov.
authors.forename: Carl J
authors.initials: CJ
authors.lastname: Percival
authors.affiliation: Atmospheric Chemistry Research Group, School of Chemistry, Cantock's Close, University of Bristol, Bristol BS8 1TS, UK. d.e.shallcross@bris.ac.uk.
authors.forename: Dudley E
authors.initials: DE
authors.lastname: Shallcross
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000032:analysis; D016902:Air Pollution, Indoor / Q000032:analysis*; D004784:Environmental Monitoring; D005466:Fluorocarbons / Q000032:analysis*; D006801:Humans; D014691:Ventilation
chemical_list: D000393:Air Pollutants; D005466:Fluorocarbons
keywords: air pollution; dispersion experiments; dynamics of indoor air contaminants; human exposure; indoor air quality (IAQ); indoor/outdoor ratio; infiltration; perfluorocarbons; tracer