Praktische Bauphysik

Lohmeyer, Gottfried C. O.

doi:10.1007/978-3-322-99656-5

Cited by 5 publications

(2 citation statements)

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“…The time budgets vary between different countries and their meteorological conditions and with age and profession of people. Lohmeyer, 1992). The main focus of this study centers about typical modern type windows in Germany.…”

Section: Methodsmentioning

confidence: 99%

Indoor and outdoor submicrometer particles: Exposure and epidemiologic relevance (“the 3 indoor Ls”)

Franck

Tuch

Manjarrez

et al. 2006

Environmental Toxicology

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Airborne particles represent a very important pollutant with respect to healthy housing conditions. The snag is that in lack of indoor data epidemiological studies focusing on submicron and ultrafine (<100 nm in diameter) particles are usually forced to use outdoor particle concentrations only. On the other hand it is known that people spend most of their time indoors. The aim of this paper is therefore to give a short comprehensive overview of the indoor/outdoor problem with regard to submicron and ultrafine particles, investigating how indoor particle size distributions correlate with outdoor concentrations in the absence of significant indoor sources. In the absence of a major indoor source, total indoor particle number concentrations were always lower than outdoor concentrations. The highest ratios between indoor and outdoor concentrations tend to correlate with lower rather than higher total outdoor particle number concentrations. Concentration ratios depend on particle size. Time lags of the correlation coefficients between the concentrations of indoor and outdoor particles of different diameters have been determined to assess the time the particles need to enter the indoor site through closed modern-type windows. Typical lag times of 0.5-3 h between somewhat smaller indoor particles and somewhat larger outdoor particles have been observed. To assess the resulting particle burden for humans, a suitably weighted average emphasizing indoor aerosol particles must be used. To classify the health effects of particles of different diameters, different decreases of particle number concentrations depending on the particle sizes must be taken into account if indoor concentrations cannot be measured and outdoor concentrations are used in place of indoor measurements. In urban areas, ultrafine particles originate primarily from rapidly increasing traffic, which is the dominating source at many urban sites. The influence of traffic on outdoor and indoor concentrations is therefore of special interest.

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Section: Methodsmentioning

confidence: 99%

Indoor and outdoor submicrometer particles: Exposure and epidemiologic relevance (“the 3 indoor Ls”)

Franck

Tuch

Manjarrez

et al. 2006

Environmental Toxicology

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“…Additional measurements using SF 6 as tracer gas yielded a mean rate of 0.16 per hour (for method cf. Lohmeyer, 1992). According to the literature, the mean air change rate measured in apartments is 0.36 per hour.…”

Section: Methodsmentioning

confidence: 99%

How do the indoor size distributions of airborne submicron and ultrafine particles in the absence of significant indoor sources depend on outdoor distributions?

et al. 2003

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Although almost all epidemiological studies of smaller airborne particles only consider outdoor concentrations, people in Central Europe actually spend most of their time indoors. Yet indoor pollutants such as organic gases, allergens and dust are known to play a prominent role, often affecting human health more than outdoor ones. The aim of this study was to ascertain how the indoor particle size distributions of submicron and ultrafine particles correlate with the outdoor concentrations in the absence of significant indoor sources. A typical indoor particle size distribution pattern has one or two modes. In the absence of significant indoor activities such as smoking, cooking etc., outdoor particles were found to be a very important source of indoor particles. The study shows that in the absence of significant indoor sources, the number of indoor concentrations of particles in this size range are clearly lower than the outdoor concentrations. This difference is greater, the higher the number of outdoor concentrations. However, the drop in concentration is not uniform, with the decrease in concentration of smaller particles exceeding that of larger ones. By contrast, the findings with larger particle sizes (diameter > 1 microm) exhibit rather linear concentration decreases. The non-uniform drop in the number of concentrations from outdoors to indoors in our measurements considering smaller particles ( >0.01 microm) is accompanied by a shift of the concentration maxima to larger particle diameters.

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