ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1992.01-24.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

AbstractA six‐week study of indoor and outdoor air pollutants was conducted in central New Jersey during the summer months of 1989. Three institutional settings for elderly and child care were investigated for the potential of acidic aerosol exposures. The indoor penetration by fine aerosols was<70% at all three institutions. For locations with closed ventilation, it was 15‐25% lower than for the open‐window setting. Relative to outdoor levels, indoor acidic sulfate aerosols were 30‐57% neutralized. Indoor levels of ammonia were = 10 × higher than corresponding outdoor values, which were consistent with calculated emission rates from human occupants. From estimates of total daily exposure, 75% of the daily dose of aerosol acidity for the elderly was due to indoor exposures. Doses received by the elderly and children ranged from 290 to 1100 nmoles of acid (15 to 55 ug as H2SO4) in a 24—h period with “worst‐case” dose received by children as high as 3400 nmoles of acid in the daytime. These doses were comparable to the levels observed in clinical and epdemiological studies where health effects result. The daily dose of acid delivered to children was calculated to be 2 to 4 × higher than the dose to the elderly population. The calculations for children indicate that more than 90% of their dose on a summer day may come from outdoor exposures. These data suggest that indoor settings are protective, but children may still be at risk from summertime acidic aerosol exposure, depending on their ac

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1992.00002.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

AbstractA dedicated research house is used to investigate the interactions of the house, and atmosphere on indoor radon concentrations. Semi‐diurnal variations of atmospheric pressure, resulting from atmospheric tides, are observed to produce differential pres‐ sures capable of driving radon‐containing sail gas into slab‐on‐grade structures built over low permeability soils. These naturally induced pressure differentials could continue to provide major contributions to radon entry when other sources of house pressurization or depressurization, and consequently outdoor air infiltration rates, are small. The observed driving force pressure differentials are well predicted from atmospheric pressure changes by a simple model based on an exponentially damped response of the sub‐slab pressures to changes in atmospheric pressure. The observed radon entry rates are in good agreement with the predictions of radon entry models developed by other investigators when time‐averaging of the driving forc

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1992.00003.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

AbstractThe most important features of Tenax and Carbotrap, solid sorbents used widely for sampling organic pollutants in air, have been tested under the conditions requested for surveys in indoor spaces and for determinations of VOC emitted from indoor sources by chamber experiments. The performances of samplers, tested with 10 nonpolar and polar (mostly lipophilic) hydrocarbons, present as vapours in 0.5 to 2.0 litre air samples, include: (a) accuracy and reproducibility of the measured concentration, (b) background or “blank” of samplers, (c) stability upon storage (at ambient and below ambient temperatures) of clean samplers and of samplers loaded with VOC, and (d) performance stability after several sampling desorption cycles. The results fulfil the requirements for both adsorbents, though each presents some different drawbacks. In particular (a) Tenax samplers show a “blank” (90 percentile) of 16 ng of benzene and 5 ng of toluene, Carbotrap samplers roughly twice as much; (b) the samplers may be stored for one month either before or after use and (c) they may withstand many cycles without discernible deteri

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1992.00004.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

AbstractThe vertical temperature profiles have been measured in a full‐scale office room ventilated by displacement. Different wall radiative emissivities have been employed to study the effect of thermal radiation. The change of the vertical locations of the heat source does not affect the stationary front, but modifies the temperature profile.Two new nodal models, i.e. a four‐node model and a multi‐node model, are developed for predicting the temperature profile based on the flow and thermal characterization in the room. Agreement between the models and the experiments are very good. The calculated results are applied to show that the temperature profile is influenced considerably by the heat conduction through the walls and the thermal radiation between the wall surfaces. The models developed can be used for design purposes, as well as to supply the thermal boundary conditions in a CFD

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1992.00005.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

AbstractThis report derives an exact, but practical, expression for calculating the stack effect from air densities and leakage distribution using the power law formulation of envelope leakage. The neutral height‐the height at which there is no stack‐related indoor‐outdoor pressure difference‐is a key intermediate in stack modeling. This report defines a computable parameter called stack height, which contains all of the leakage distribution information necessary for estimating stack flows, thus freeing the model from specific assumptions (e.g. that the leakage is separable into evenly distributed floor, wall, and ceiling components). Example calculations, including comparisons with other models, as well as validations using measured data from dwellings, are also presented. The dimensionless neutral level, which is related to the neutral height, is often used as an indicator of leakage distribution and in superposition. Its definition and role in these instances are discussed in detail. The more exact formulation is then used to analyze the simple box cases normally assumed in infiltration modeling and other approximations. Measured ventilation data will be used to infer leakage distributions and neutral levels as well as for example calcu

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1992.00006.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

AbstractThe main source of high radon concentration indoors is the exhalation of radon from the soil. In the western part of Germany, two interesting regions, “Eifel” and “Hunsrück”, are selected for these radon investigations. The first region is an area with silt and sandstone of low uranium content but with tectonic fractures caused by postvolcanic activity, whereas in the part of the “Hunsrück” under consideration, the uranium concentration in the ground formerly allowed the extraction of uranium ores. An electrostatic deposit of the first radon daughter (Polonium‐218‐ion) onto a surface barrier detector and the subsequent analysis of the measured alpha spectra enables the determination of the concentration of radon in dwellings, its diffusion through and its exhalation rate from the soil. A maximum indoor concentration of radon of 8 kBq★m−3in a bedroom and approximately 35 kBq★m−3in a cellar room were determined in a house built in 1976. The daily variation between the minimum and the maximum concentration indoors amounts to a factor of ten. In these regions the radon concentration outdoors varies between 20 and 150 Bq★m−3. The exhalation rates of radon from the soil are found to range from 0.002 to 1 Bq★m−2★S−1The effects of sealing the ground slab with polyurethane and removing the air under the gro

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1992.00007.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

AbstractThis paper is based on field measurements in auditoria, carried out in Norway and in Switzerland. In both cases carbon dioxide (CO2was chosen as the relevant indicator to establish ventilation demand.Investigations in Norway focus on the aspects of airflow, patterns, ventilation efficiency and air quality. Intensive monitoring and numerical calculations with the computer codeKAMELEONwere performed.The Swiss project places more emphasis on impacts of demand control on energy consumption and occupant response. The results of the fild measurements, of the questioning of occupants, as well as of simulations which were carried out with the simulation codeTRNSYSare presented.Results show that demand control with CO2, as indicator for ventilation demand can maintain an acceptable indoor climate while allowing substantial energy savings.These investigations were conducted as part of the IEA (International Energy Agency) research programme “Annex 18: Demand Controlled Ventilating Systems

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1992.00008.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

AbstractAn analysis has been completed of the performance, mechanisms, and costs of alternative technologies for preventing radon entry into the living areas of houses having crawl‐space foundations. Sub‐membrane depressurization (SMD) is consistently the most effective technique, often providing radon reductions of 80‐98% in the living area. It has a relatively high installation cost, but a moderate annual operating cost. Forced crawl‐space depressurization is the second most effective, giving reductions of 70‐96%. Crawl‐space depressurization is less well demonstrated than is SMD, and performance will vary with crawl‐space tightness and weather, but it will be a primary option when large radon reductions are needed in buildings with crawl‐spaces which are inaccessible for installation of SMD. Crawl‐space depressurization has a lower installation cost than SMD, but its operating cost may be three times higher.Natural crawl‐space ventilation and forced crawl‐space pressurization each typically provides roughly 50% reduction or less in the living area. The lack of a clear benefit of crawl‐space pressurization in most installations probably indicates that the crawl space is in fact not being pressurized. Crawl‐space sealing and barriers (as stand‐alone methods) usually

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1992.00009.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY