Indoor and outdoor concentrations of airborne fine parti cles from internal combustion engines have been mea sured over periods of 24 h with a time resolution of 10 s. With this time series, the ventilation air exchange rate of different rooms has been computed using a novel ap proach to the solution of the mass balance equation. A 'mixing time' parameter has been introduced in order to account for the initial non-homogeneous distribution of the pollutants in the rooms. It is demonstrated that this method can be used to determine the impact of health- relevant outdoor particles on the indoor particle concen tration. This yields information on the protection a build ing offers against pollutants entering from outdoors.
Schwartz J., Dockery DW, Neas LM: Is daily mortality associated specifically with fine particles ?J Air Waste Manage Assoc1996;46: 927-939.
2.
Seaton A., MacNee W, Donaldson K, Godden D: Particulate air pollution and health effects . Lancet1995;345:176-178.
3.
Dockery DW, Pope CA, Xu X., Spengler JD, Ware JH, Faye ME, Ferris BG, Speizer FE: An association between air pollution and mortality in six US cities . N Engl J Med1993;329:1753-1759.
4.
Braun-Fahlander C., Ackermann-Liebrich U., Schwartz J., Gnehm HP, Rutishauser M., Wanner HU: Air pollution and respiratory symptoms in pre-school children. Am Rev Respir Dis1992; 145:42-47.
5.
Wallace L.: Indoor particles: A review. Air Waste Manage Assoc1996;46:98-126.
6.
Chao Cyh, Tung Tcw, Burnett J.: Influence of different indoor activities on the indoor particulate levels in residential buildings. Indoor Built Environ1998;7:110-121.
Koutrakis P. , Briggs Slk, Leaderer BP: Source apportionment of indoor aerosols in Suffolk and Onondaga Counties and New York. Environ Sci Technol1992;26:521-527.
9.
Roulet CA: Messmethoden zur Beurteilung des Energieverbrauchs und des Komforts. Forschungsprogramm Energierelevante Luftströmungen in Gebäuden. Technical report, Zürich, Bundesamt für Energiewirtschaft , 1994.
Thatcher TL , Layton DW: Deposition, resuspension, and penetration of particles within a residence. Atmos Environ1995 ;29:1487-1497.
12.
Leaderer BP , Schaap L., Dietz RN: Evaluation of the perfluorocarbon tracer technique for determining infiltration rates in residences. Environ Sci Technol1985;19:1225-1232.
13.
Cheong KW, Riffat SB: New approach for measuring air flows in buildings using a perfluorocarbon tracer. Appl Energ1995 ;51:223-232.
14.
Sherman MH: Analysis of errors associated with passive ventilation measurement techniques . Building Environ1989;24:131-139.
15.
Sherman MH: Tracer-gas techniques for measuring ventilation in a single zone. Building Environ1990;25:365-374.
16.
Burtscher H. : Measurement and characteristics of combustion aerosols with special consideration of photoelectric charging and charging by flame ions. J AerosolSci1992;23:549-595.
17.
Filippov AV, Schmidt-Ott A., Fendel W.: Escape probability of photoelectrons from particles. J AerosolSci1993;24(suppl 1):S501-S502.
18.
Wilson NK, Barbour RK: Evaluation of a real-time monitor for fine particle-bound PAHs in air. Polycyclic Aromatic Compounds1994;5: 167-174.
19.
Hart KM, McDow SR, Giger W., Steiner D., Burtscher H.: The correlation between in-situ, real-time aerosol photo-emission intensity and particulate polycyclic aromatic hydrocarbon in combustion aerosols . Water Air Soil Pollut1993;68:75-90.
20.
McDow SR, Giger W., Burtscher H., Schmidt-Ott A., Siegmann HC: Polycyclic aromatic hydrocarbons and combustion aerosol photo-emission . Atmos Environ1990;24A:2911-2916.
21.
Switzer P., Ott W.: Derivation of an indoor air averaging time model from the mass balance equation for the case of independent source inputs and fixed air exchange rates. J Expo Anal Environ Epidemiol1992;2(suppl 2): S113-S135.
22.
Dockery DW, Spengler JD: Indoor-outdoor relationships of respirable sulphates and particles . Atmos Environ1981;15:335-343.
23.
Ott W., Switzer P., Robinson J.: Particle concentrations inside a tavern before and after prohibition of smoking: Evaluating the performance of an air quality model. J Air Waste Manage Assoc1997;46:1120-1134.
24.
Raunemaa T. , Kulmala M., Saari H., Olin M., Kulmala MH: Indoor air aerosol model: Transport indoors and deposition of fine and coarse particles. Aerosol Sci Tech1989;11:11-25.
25.
Ozkaynak H. , Xue J., Spengler JD, Wallace L., Pellizzari ED, Jenkins P.: Personal exposure to airborne particles and metals: Results from the particle team study in Riverside, California. J Expo Anal Environ Epidemiol1996;6:57-78.
26.
Kogelschatz U.: Silent-discharge driven excimer UV light sources and their applications. ApplSurf Sci1992;54:410-423.
27.
Press WH, Teukolsky SA, Vetterling WT, Flannery BR: Numerical Recipes in C. The Art of Scientific Computing. Cambridge University Press, ed 2 rev, 1992.
