Mitigation of the effective dose of radon decay products through the use of an air cleaner in a dwelling in Okinawa, Japan

Kranrod, Chutima; Tokonami, Shinji; Ishikawa, Tetsuo; Janik, Mirosław; Shingaki, Reina; Furukawa, Mutsuhisa; Chanyotha, Supitcha; Chankow, Nares

doi:10.1016/j.apradiso.2009.02.087

Cited by 25 publications

(14 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Based on this survey, it was estimated that only 0.1% of dwellings in Japan exceed 100 Bq/m³ radon concentration, which the WHO suggests as a reference level for indoor radon [8]. On the other hand, 'radon hot-spots' on Okinawa Island with relatively high indoor radon concentration, exceeded 300 Bq/m 3 , described by Kranrod [9] was found. Moreover, from the long-term survey performed by Kobayashi [10], the radon concentration in a house located near Futsukaichi hot spring ranged from 14 to 184 Bq/m 3 with an arithmetic mean of 45 Bq/m 3 .…”

Section: Descriptive Statisticsmentioning

confidence: 99%

Analysis of simultaneous time series of indoor, outdoor and soil air radon concentrations, meteorological and seismic data

Janik¹,

Bossew

2016

Nukleonika

View full text Add to dashboard Cite

It is well known that the temporal dynamic of indoor and outdoor radon concentrations show complex patterns, which are partly not easy to interpret. Clearly, for physical reasons, they must be related to possibly variable conditions of radon generation, migration and atmospheric dispersion and accumulation. The aim of this study was to analyse long-time series of simultaneously measured indoor and outdoor radon concentrations, together with environmental quantities, which may act as control variables of Rn. The study was performed in Chiba, Japan, using two ionization chambers for parallel indoor and outdoor radon concentrations measurements over 4 years. Meteorological and seismic data were obtained from the Japan Metrological Agency (JMA).

show abstract

Section: Descriptive Statisticsmentioning

confidence: 99%

Analysis of simultaneous time series of indoor, outdoor and soil air radon concentrations, meteorological and seismic data

Janik¹,

Bossew

2016

Nukleonika

View full text Add to dashboard Cite

show abstract

“…Among other mitigation approaches, filtration has a relatively long history in mitigating the inhalation exposure from radon decay products. A variety of methods such as electro-filter, an air cleaner with a mechanical filter (Kojima et al., 1992) and high-efficiency particulate air filter (HEPA filter; Kranrod et al., 2009; Rajala et al., 1985; Yasuoka et al., 2009) have been tested. However, no significant effect is noted so far.…”

Section: Resultsmentioning

confidence: 99%

Radon interventions around the globe: A systematic review

Khan

Gomes

Krewski

2019

Heliyon

View full text Add to dashboard Cite

Background Radon is the primary source of environmental radiation exposure posing a significant human health risk in cold countries. In Canada, most provinces have revised building codes by 2017, requiring construction solutions to avoid radon in all new buildings. While various construction solutions and remediation techniques have been proposed and evaluated, the question about the best method that would effectively reduce radon in a variety of contexts remained unanswered. Radon practitioners, officials of radon control programs, and businesses offering radon testing and mitigation services, builders, property managers, homeowners and residents also have similar queries. Objective This paper systematically reviewed both experimental and observational studies (S) with radon interventions (I) used globally in residential houses (P) compared to other residential or model houses (C) to evaluate relative mitigation effectiveness (O) that could guide selecting the best radon reduction strategy for residential buildings. Methods Two researchers searched fifteen academic bibliographic and grey literature databases for radon intervention studies conducted around the world, with particular emphasis on areas of North America and Europe published from 1990 to 2018. Interventions in residential and model houses were included, but studies piloted purely in the lab were excluded; the PRISMA checklist was used to synthesize data; Cochrane and Hamilton tools were used to evaluate study quality. Results Studies around the globe have investigated a variety of construction solutions, radon mitigation and remediation systems with different levels of effectiveness. In most cases, sub-slab or sump depressurization system (SSDS) with active ventilation technique was found more effective in achieving a significant and sustained radon reduction than the passive methods such as sealing, membrane, block and beam, simple ventilation, or filtration. The choice of an optimal strategy largely depends on the factors related to the initial radon level, routes of entry, building design and age, as well as other geologic, atmospheric, and climatic conditions. Conclusion Although an active SSDS is the best mitigation systems, at places, it needs to be combined with another system and installed by a trained radon professional considering the pertinent factors to ensure radon level continues to remain below the action level. This study did not conduct any economic evaluation of the mitigation measures. Future review with studies on the implementation of new building codes will provide updated evidence. Recommendation For the practical implementation of radon mitigation, training of the construction industry, information provision for residents, the establishment of public funds, incorporation of radon-prone areas in the land utilization maps, and enacting building codes deemed ...

show abstract

“…The AMAD of 214 Bi was calculated to be 350 nm with relative geometric standard deviation of 3. (16) have been measured the activity size distribution of the attached radon progeny by a Micro Orifice Uniform Deposit impactor (Model 110 MOUDITM, USA) in Okinawa. The AMAD was observed 267 nm with a range from 234 to 308 and a GSD of 1.7 (range 1.6 and 1.9) which is smaller than our present value Mishra et al (17) have been measured the activity size distribution of the attached aerosols by a developed low pressure cascade impactor.…”

Section: Indoor Activity Size Distribution Ofmentioning

confidence: 99%

“…This distribution has been determined by tagging natural aerosol particles with radon progeny. However, some measurements for attached and unattached activity size distributions of 222 Rn progeny have been performed in the indoor air under realistic natural conditions (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17) . Most of the observed data have shown that the size distribution of radon progeny consists of ultrafine clusters with median diameters below 4 nm (unattached activity) and progenies associated with ambient aerosol particles in sizes ranging between 100 and 1000 nm (attached activity).…”

mentioning

confidence: 99%

Lung Depth Dose from Inhalation of 222Rn Progeny

2012

Egypt. J. Biophys. Biomed. Engng.

View full text Add to dashboard Cite

N THE CASE of internally deposited radionuclides, direct ……measurement of the energy absorbed from ionizing radiation emitted by the decaying of these radionuclides is rarely, if ever, possible. Therefore, one must rely on dosimetric models to obtain estimates of the spatial and temporal patterns of energy deposition in human lung. These models always require information about the parameters of activity size distributions of radon progeny. In the present work, the attached and unattached activity size distribution of 222 Rn progeny ( 214 Bi and 214 Po) were measured in indoor air of Minia University, Minia, Egypt. The attached fraction was collected using a low-pressure Berner cascade-impactor technique. A constructed wire screen diffusion battery was used for collecting the unattached fraction. Most of the attached activities for 214 Bi progeny were associated with the aerosol particles of the accumulation mode. The AMAD of this mode for 214 Bi was determined to be 350 nm with GSD of 3. The GSD of unattached size distributions for 214 Po is 1.29 with AMTD of 1.25 nm. An analytical method has been developed to compute the local energy deposition of 214 Po alpha particles in a target volume of 1 m spheres located at different depths in bronchial epithelium. In order to reach the target, alpha particles travel either through tissue alone or through air and tissue. While the depth-dose distributions in the case of nuclides uniformly distributed within the epithelium were practically constant with depth, they decreased in an almost linear fashion with increasing depth in the case of nuclides on the airway surface.

show abstract

Mitigation of the effective dose of radon decay products through the use of an air cleaner in a dwelling in Okinawa, Japan

Cited by 25 publications

References 30 publications

Analysis of simultaneous time series of indoor, outdoor and soil air radon concentrations, meteorological and seismic data

Analysis of simultaneous time series of indoor, outdoor and soil air radon concentrations, meteorological and seismic data

Radon interventions around the globe: A systematic review

Lung Depth Dose from Inhalation of 222Rn Progeny

Contact Info

Product

Resources

About