scholarly journals THE INFLUENCE OF AEROSOL CONCENTRATION ON CHANGES IN THE VOLUMETRIC ACTIVITIES OF INDOOR RADON SHORT-TERM DECAY PRODUCTS

2010 ◽  
Vol 2 (5) ◽  
pp. 81-86 ◽  
Author(s):  
Diana Politova ◽  
Dainius Jasaitis
Keyword(s):  
Particle Concentration ◽  
Indoor Radon ◽  
Aerosol Particles ◽  
Alpha Particles ◽  
Aerosol Concentration ◽  
Short Term ◽  
Volumetric Activity ◽  
Equilibrium Factor ◽  
Decay Products ◽  
Unattached Fraction

The article describes the influence of aerosol concentration on changes in the volumetric activities of indoor radon short-term decay products. The concentration of aerosol in the air, equilibrium factors and unattached fraction were measured under normal living conditions when the concentration of aerosol increases, i.e. burning a candle or frankincense in accommodations, smoke-filled accommodations, a steamy kitchen etc. It has been established that when the concentration of aerosol in the air rises, the number of free atoms of radon short-term decay products attached to aerosol particles also increases, and therefore higher volumetric activity of alpha particles is fixed. A tight positive connection of the correlation between equilibrium factor (F) and aerosol particle concentration in the air of accommodations as well as a negative correlation between unattached fraction and an equilibrium factor have been determined.

scholarly journals Radon decay products and 10–1100 nm aerosol particles in Postojna Cave

2013 ◽  
Vol 13 (3) ◽  
pp. 823-831 ◽  
Author(s):  
M. Bezek ◽  
A. Gregorič ◽  
J. Vaupotič
Keyword(s):  
Activity Concentration ◽  
Size Range ◽  
Aerosol Particles ◽  
Number Concentration ◽  
Decay Products ◽  
Calculated Dose ◽  
Radon Decay ◽  
Unattached Fraction ◽  
The Difference ◽  
Key Parameter

Abstract. At the lowest point along the tourist route in Postojna Cave, the activity concentration of radon (222Rn) decay products and the number concentration and size distribution of aerosol particles in the size range of 10–1100 nm were monitored, with the focus on the unattached fraction (fun) of radon decay products (RnDPs), a key parameter in radon dosimetry. The total number concentration of aerosols during visits in summer was lower (700 cm−3) than in winter (2800 cm−3), and was dominated by <50 nm particles (related to unattached RnDPs) in summer and by >50 nm particles (related to the attached RnDPs) in winter. This explains the higher fun values in summer (0.75) and the lower winter measurement (0.04) and, consequently, DCFD values of 43.6 and 13.1 mSv WLM−1 respectively for the calculated dose conversion factors. The difference is caused by an enhanced inflow of fresh outside air, driven in winter by the higher air temperature in the cave compared to outside, resulting in the introduction of outside aerosol particles into the cave.

UNATTACHED 212PB FRACTION IN THE WORKER’S BREATHING ZONE AT HIGH THORON CONCENTRATIONS

2020 ◽  
Vol 191 (2) ◽  
pp. 150-153
Author(s):  
Michael Zhukovsky ◽  
Maksim Vasyanovich ◽  
Aleksandra Onishchenko
Keyword(s):  
Experimental Data ◽  
Aerosol Particles ◽  
Inhalation Exposure ◽  
Storage Facility ◽  
Breathing Zone ◽  
High Concentration ◽  
Sampling Device ◽  
Decay Products ◽  
Unattached Fraction ◽  
Dynamic Shift

Abstract Classical aerosol physics predicts that it is impossible to observe noticeable values of the unattached fraction of decay products of thoron at typical concentrations of aerosol particles. The experimental data have shown that the unattached fraction of the thoron decay products in a monazite storage facility is in the range 0.3–0.6. This effect is caused by local increase in air exchange near the inlet of the sampling device at high 220Rn concentrations. It was found that a dynamic shift between the unattached and attached thoron decay products is also observed in the worker’s breathing zone at a high concentration of thoron. The 212Pb unattached fraction in worker’s breathing zone was ~0.4. It demonstrates that when evaluating inhalation exposure to the products of the decay of thoron, it is necessary to take into account the increase of the 212Pb unattached fraction in the worker’s breathing zone.

scholarly journals THE RESULTS OF MEASURING AND MODELLING SOIL-INDOORS RADON TRANSPORTATION / RADONO PERNAŠOS IŠ DIRVOŽEMIO Į PATALPAS MATAVIMO IR MODELIAVIMO REZULTATAI

2013 ◽  
Vol 5 (4) ◽  
pp. 388-396 ◽  
Author(s):  
Erika Streckytė ◽  
Donatas Butkus
Keyword(s):  
Moisture Content ◽  
Indoor Radon ◽  
Ambient Air ◽  
Summer Season ◽  
Monitoring Device ◽  
Volumetric Activity ◽  
Indoor Temperature ◽  
Radon Gas ◽  
Radon Monitoring ◽  
Radon Concentrations

The article presents the entry of radon gas into premises and introduces the parameters accelerating and slowing this process. The paper determines the dependence of radon gas entering the premises on ambient temperature and humidity changes. It is noted that a growth in differences under ambient and indoor temperature increases indoor radon concentrations in the air due to an increase in the intensity of radon exhalation from soil. Also, an increase in the moisture content indoors decreases the volumetric activity of radon in the air. The simulated values of radon volumetric activity in ambient air were similar to those measured using radon monitoring device RTM2200. Radon concentration in the air of the first floor was higher than that in the second floor. Indoor radon concentrations were highest in the winter and lowest in summer season. Article in Lithuanian. Santrauka Nagrinėjama radono dujų patekimo į patalpas procesas, šį procesą spartinantys ir lėtinantys parametrai. Nustatoma radono dujų patekimo į patalpas priklausomybė nuo aplinkos temperatūros bei drėgnio kitimo. Pastebėta, kad, didėjant aplinkos ir patalpos temperatūrų skirtumui, didėja ir radono tūrinis aktyvumas patalpos ore (vasarą radono tūrinis aktyvumas siekė 45,0±3,0 Bq/m3, kai temperatūrų skirtumas buvo 3,1 °C, o rudenį – 62,0±5,0 Bq/m3, esant temperatūrų skirtumui 3,9 °C), didėja radono ekshaliacijos iš dirvožemio intensyvumas, o didėjant drėgmės kiekiui patalpose radono tūrinis aktyvumas ore mažėja. Sumodeliuotos radono tūrinio aktyvumo patalpos ore reikšmės buvo panašios kaip ir išmatuotos naudojant radono monitorių RTM2200. Pirmajame aukšte radono tūrinis aktyvumas ore buvo didesnis nei antrajame. Žiemos sezonu jo vertė buvo didžiausia (47,0±10,5 Bq/m3), o vasaros sezonu – mažiausia (15±1,8 Bq/m3).

The Alpha Particle Doses Received by Students and Staff in Twenty Schools in the North of Hebron Region - Palestine

2021 ◽  
Vol 14 (4) ◽  
pp. 309-316
Keyword(s):  
Effective Dose ◽  
Radon Concentration ◽  
Annual Effective Dose ◽  
Indoor Radon ◽  
Alpha Particles ◽  
Indoor Radon Concentration ◽  
The North ◽  
Cr 39 Detectors ◽  
Average Effective Dose ◽  
Radon Concentrations

Abstract: The aim of the current study was to measure indoor radon concentration levels and its resulting doses received by the students and staff in schools of the directorate of education in the north of Hebron region- Palestine, during the summer months from June to September (2018), using CR-39 detectors. In this study, a total of 567 CR-39-based radon detectors were installed in the selected schools. The average radon concentrations were found to be 90.0, 66.5 and 58.0 Bqm-3 in Halhul, Beit Umar and Alarrub camp schools, respectively. Based on the measured indoor radon data, the overall average effective dose for the studied area was found to be 0.31 mSvy-1. Reported values for radon concentrations and corresponding doses are lower than ICRP recommended limits for workplaces. The results show no significant radiological risk for the pupils and staff in the schools under investigation. Consequently, the health hazards related to radiation are expected to be negligible. Keywords: Radon concentration, Alpha particles, Annual effective dose, Schools. PACs: 29.40.−n.

THE INFLUENCE OF THE EQUILIBRIUM FACTOR ON THE ESTIMATED ANNUAL EFFECTIVE DOSE FROM INHALED RADON DECAY PRODUCTS IN SELECTED WORKPLACES

2020 ◽  
Vol 191 (2) ◽  
pp. 188-191
Author(s):  
Petr P S Otahal ◽  
Ivo Burian ◽  
Eliska Fialova ◽  
Josef Vosahlik
Keyword(s):  
Effective Dose ◽  
Activity Concentration ◽  
Annual Effective Dose ◽  
Radiological Protection ◽  
Equilibrium Factor ◽  
Decay Products ◽  
Water Treatment Plants ◽  
Radon Decay ◽  
Effective Doses ◽  
Dose Coefficients

Abstract Measurements of activity concentration of radon gas and radon decay products were carried out in several workplaces including schools, radium spas, swimming pools, water treatment plants, caves and former mines. Based on these measurements, annual effective doses to workers were estimated and values of the equilibrium factor, F, were calculated. This paper describes the different approaches used to estimate the annual effective dose based on the dose coefficients recommended by the International Commission on Radiological Protection. Using the measured F values as opposed to the default F value of 0.4 changed the doses by about 5–95% depending mainly upon the ventilation conditions of the workplace.

scholarly journals Short-Term Measurement of Indoor Radon Concentration in Northern Croatia

2020 ◽  
Vol 10 (7) ◽  
pp. 2341 ◽  
Author(s):  
Anita Ptiček Siročić ◽  
Davor Stanko ◽  
Nikola Sakač ◽  
Dragana Dogančić ◽  
Tomislav Trojko
Keyword(s):  
Radon Concentration ◽  
Indoor Radon ◽  
Geometric Mean ◽  
Construction Materials ◽  
Health Issues ◽  
Short Term ◽  
Indoor Radon Concentration ◽  
Ground Floor ◽  
Northern Croatia ◽  
Radon Concentrations

(1) Background: Radon concentrations in the environment are generally very low. However, radon concentrations can be high indoors and can cause some serious health issues. The main source of indoor radon (homes, buildings and other residential objects) can be soil under the house, while other sources can be construction materials, groundwater and natural gas. Radon accumulates mainly in the lower levels of the buildings (especially low-ventilated underground levels and basements). (2) Methods: in this paper, we have measured the indoor radon concentrations at 15 locations in various objects (basements and ground floor/1st floor rooms) in the area of northern Croatia. (3) Results: the results show a higher concentration of radon in the basement area in comparison to values measured in the ground floor and first-floor rooms. The arithmetic mean (AM) and geometric mean (GM) of basement rooms were 70.9 ± 38.8 Bq/m3 and 61.2 ± 2.2 Bq/m3 compared to ground floor and first-floor rooms 42.5 ± 30.8 Bq/m3 and 32.8 ± 2.9 Bq/m3, respectively. (4) Conclusions: results obtained (AM and GM values) are within the maximal allowed values (300 Bq/m3) according to the Euroatom Directive. However, there are periods when maximum radon concentration exceeds 300 Bq/m3. Indoor radon concentrations vary with the occupancy of the rooms and it is evident that the ventilation has significant effect on the reduction of concentration.

Air ions as indicators of short-term indoor radon variations

2015 ◽  
Vol 99 ◽  
pp. 179-185 ◽  
Author(s):  
P. Kolarž ◽  
Z. Ćurguz
Keyword(s):  
Indoor Radon ◽  
Air Ions ◽  
Short Term
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