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- Afshari, A, et al.
(författare)
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Characterization of indoor sources of fine and ultrafine particles: a study conducted in a full scale chamber
- 2005
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Ingår i: Indoor Air. - : Hindawi Limited. - 1600-0668 .- 0905-6947. ; 15:2, s. 141-150
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Tidskriftsartikel (refereegranskat)abstract
- Humans and their activities are known to generate considerable amounts of particulate matter indoors. Some of the activities are cooking, smoking and cleaning. In this study 13 different particle sources were for the first time examined in a 32 m3 full-scale chamber with an air change rate of 1.7 ± 0.1/h. Two different instruments, a condensation particle counter (CPC) and an optical particle counter (OPC) were used to quantitatively determine ultrafine and fine particle emissions, respectively. The CPC measures particles from 0.02 μm to larger than 1.0 μm. The OPC was adjusted to measure particle concentrations in eight fractions between 0.3 and 1.0 μm. The sources were cigarette side-stream smoke, pure wax candles, scented candles, a vacuum cleaner, an air-freshener spray, a flat iron (with and without steam) on a cotton sheet, electric radiators, an electric stove, a gas stove, and frying meat. The cigarette burning, frying meat, air freshener spray and gas stove showed a particle size distribution that changed over time towards larger particles. In most of the experiments the maximum concentration was reached within a few minutes. Typically, the increase of the particle concentration immediately after activation of the source was more rapid than the decay of the concentration observed after deactivation of the source. The highest observed concentration of ultrafine particles was approximately 241,000 particles/cm 3 and originated from the combustion of pure wax candles. The weakest generation of ultrafine particles (1.17 × 107 particles per second) was observed when ironing without steam on a cotton sheet, which resulted in a concentration of 550 particles/cm3 in the chamber air. The highest generation rate (1.47 × 1010 particles per second) was observed in the radiator test.
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- Matson, Uve, 1977, et al.
(författare)
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Indoor and outdoor measurements of ultra fine particles in a medium-size and large city
- 2003
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Ingår i: Healthy Buildings 2003 - Proceedings 7th International Conference.
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Konferensbidrag (refereegranskat)abstract
- The concentrations of ultra fine particles (UFPs) were measured in the medium-size city ofGothenburg, Sweden, in the large city of Copenhagen and at a rural site in Denmark. InGothenburg, field measurements were conducted both in several residential and officebuildings, while in Denmark measurements comprise two office buildings, one of themlocated at a rural site. Concentrations of UFPs were measured simultaneously indoors andoutdoors. The results revealed that outdoor levels are major contributors to the indoor particlenumber concentration and the variability in concentrations is less pronounced indoors whenno indoor sources are present. The magnitude of UFP concentrations is higher in the large citycompared to the medium-size city. The results showed that in the Gothenburg office buildingsthe UFP concentrations indoors were fairly correlated to that outdoors. Another differencebetween Danish and Swedish offices is that in Denmark tobacco smoking is a main indoorsource of UFPs. The results from a Swedish residential building show that the indoorconcentration was strongly influenced by the indoor activity, e.g. cooking, ironing and byoutdoor levels mainly during window airing.
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