ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1995.01-52.x

出版商:Munksgaard International Publishers    

年代:1995

数据来源: WILEY

摘要:

AbstractAccording to the Californian Safe Drinking Water and Toxic Enforcement Act, Proposition 65 (State of California, 1986) the manufacturers and retailers of products (such as furniture and fittings) which emit formaldehyde are obliged to either mark their products with a warning label or provide evidence that their products do not pose a significant cancer risk to the consumer. The significant risk is defined as 1 case of cancer in a population of 100,000 persons within a period of exposure of 70 years (State of California, 1992).In this study, a large‐scale climate chamber test of a full set of furniture and fitments was made. The formaldehyde concentration in a test chamber peaked at about 112 μg/m3within a day after the furniture had been installed. After 8 weeks the concentration leveled out at about 50 μg/m3.Various models were used to predict occupant exposures in homes containing the same furniture and fitments; multi‐compartment models identified a short‐term compartment with a half‐life of between 5.2 and 6.0 h and a relative source strength of between 75% and 30% of the total source strength; a medium‐term compartment with a half‐life of between 14 and 81 days; and a long‐term compartment for which the best estimate of a half‐life was 384 days.The accumulated dose of formaldehyde absorbed by an occupant during 70 years of exposure in the hypothetical home was estimated by extrapolation using the same models. The dose was found to be in the range of 0.13 g to 0.16 g.The concentration in the test chamber showing a maximum value of 112 μg/m3formaldehyde may cause discomfort among hypersensitive persons during the first couple of days. The risk estimates based on the estimated long‐term dose indicate that the cancer risks associated with the exposure caused by furniture are in the range of 6.9 to 8.9 × 10−8, based on monkey data, and 5.8 to 7.4 × 10−7, based on rat data.In conclusion, a successful draft protocol was established for tests in relation to Proposition 65 and, with the limitations of this exploratory study, the actual furniture equipment is considered to cause no significant cancer risk to the consumer ac

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1995.t01-2-00002.x

出版商:Munksgaard International Publishers    

年代:1995

数据来源: WILEY

摘要:

AbstractThe results of measurements of indoor air formaldehyde concentrations in occupational and private residences are presented for the period 1986 to 1993, based on requests of persons who complained about irritations. In many cases, climatic parameters such as the air exchange rate, temperature and relative humidity were also monitored. Calculated mean values for temperature and humidity were 22°C and 45% respectively. The average air exchange rate was 0.36 h−1, which is well below a recommended guideline value of 0.8 h˜' and it was evident that the ventilation is clearly insufficient in many rooms. The average formaldehyde concentration was 119 μg/m−3(252 data), which is only slightly below the German guideline value of 125 μg/m−3. In 31% of the cases this guideline was exceeded. As expected, a clear relation between formaldehyde concentrations and the air exchange rate was found. The highest levels result at AE≤0.8 h−1, but only a single value exceeds 125 μg/m−3at AE≥0.8 h−1. The association of law ventilation rates with high formaldehyde levels is also evident from a comparison with theoretical data after normalization to AE=0.8 h−1, using the Hoetjer‐equation. It was also observed that the calculated annual mean concentrations dec

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1995.t01-2-00003.x

出版商:Munksgaard International Publishers    

年代:1995

数据来源: WILEY

摘要:

AbstractThe mean skin temperatures as well as the temperatures of the hands, feet and forehead of small children were measured in nurseries at air temperatures of 20°C and 22°C. Differences were studied between babies remaining still, babies crawling on tiling, wooden floors or rubber foam groundsheets, and older walking children. The results suggest that an air temperature of 22°C leads to skin temperatures comparable to those observed for resting adults in comfort, while 20°C seems to induce a slight but overall cooling of the body and considerable cooling of the extremities for the babies remaining still. The material of floor coverings should be considered carefully and preference given to low conductivity materials. Assuming that the optimum skin temperatures are the same for children and for adults, it appears that the PMV‐PPD approach can be used to predict this particular optimum comfort condition, provided an increase of 20 wm−2is taken into account for the metabolic rate of the small c

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1995.t01-2-00004.x

出版商:Munksgaard International Publishers    

年代:1995

数据来源: WILEY

摘要:

AbstractVentilation displacement systems have, during the last ten years, become more and more popular. In these systems cool air is supplied to the room, and the air is heated by heat sources. The rising air above these heat sources is of paramount importance to the behaviour of the ventilation displacement systems. In the present work the turbulent flow in plumes is studied numerically, using finite volume methods. The standard r‐ɛ model was found to underpredict the spreading of the plumes, and it was thus modified in two ways so as to predict spreading rates in agreement with experiments. We present a comprehensive comparison between predictions and experiments including spreading rates, velocity and temperature profiles, and turbulent shear stresses. The volume flow rate versus the vertical distance from the plume is also presented. Good agreement between predictions and experiments is obtain

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1995.t01-2-00005.x

出版商:Munksgaard International Publishers    

年代:1995

数据来源: WILEY

摘要:

AbstractAccording to the Environmental Protection Agency (EPA) and other public health agencies in the United States, radon may be the leading cause (along with passive smoking) of lung cancer deaths among nonsmokers. Radon is estimated to be the second leading cause of lung cancer death in smokers behind smoking‐related lung cancer. EPA estimates that 7,000 to 30,000 lung cancer deaths each year are due to radon exposure. (It is implied that radon‐related lung cancer deaths can be prevented by reducing radon levels below EPA's guideline levels.) Current EPA radon policy is based on a strategy of education, the transfer of testing and remediation technologies to the public and private sectors, and recently proposed radon‐resistant construction standards for new homes. This paper models the effectiveness of current, proposed, and alternative policies for reducing radon risks in U.S. residential construction. The results of our analysis suggest that EPA's projections of 2,200 “lives saved annually” as a result of its current action level of 4 pCi/l will not be achieved with its current policy in the near future. Overall, the response of radon‐related mortality to most policy options is delayed and flat due in pan to the large number of houses with low radon levels and the long latency period between radon exposure and the development of cancer. The modeling results suggest that more aggressive smoking reduction programs may yield greater benefits in overall lung cancer mortality (but not reduced radon exposure) than most radon‐rel

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1995.t01-2-00006.x

出版商:Munksgaard International Publishers    

年代:1995

数据来源: WILEY

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1995.t01-2-00007.x

出版商:Munksgaard International Publishers    

年代:1995

数据来源: WILEY

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1995.t01-2-00008.x

出版商:Munksgaard International Publishers    

年代:1995

数据来源: WILEY