scholarly journals 222Rn Exhalation Rates from Some Granite and Marble Used in Korea: Preliminary Study

Atmosphere ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 1057
Author(s):  
Hyewon Lee ◽  
Jungsub Lee ◽  
Sungwon Yoon ◽  
Cheolmin Lee
Keyword(s):  
Building Materials ◽  
Evaluation Method ◽  
International Standards ◽  
Test Method ◽  
Closed Chamber ◽  
Radon Exhalation ◽  
Hazardous Chemical ◽  
Preliminary Study ◽  
Radon Exhalation Rates ◽  
International Standards Organization

The objective of this study was to establish a test method for assessing radon exhalation rates from building materials considering radon related environmental policy and research in Korea. This method was established in consideration of cost-effectiveness based on the International Standards Organization (ISO) method and the closed chamber method, which is an evaluation method for the emission of hazardous chemical substances from building materials in Korea. The assessment of radon exhalation rates from five types each of granite and marble used in the construction industry in Korea gave mean radon exhalation rates of 0.497 ± 0.467 Bq/m2∙h from granite and 0.193 ± 0.113 Bq/m2∙h from marble, indicating higher radon exhalation rates from granite. These results are consistent with those of a previous study, indicating that granites are more likely to show higher radon exhalation rates than marbles.

Radioactivity and radon exhalation rates of building materials in The Netherlands

1985 ◽  
Vol 45 ◽  
pp. 151-156 ◽  
Author(s):  
J.G. Ackers ◽  
J.F. Den Boer ◽  
P. De Jong ◽  
R.A. Wolschrijn
Keyword(s):  
The Netherlands ◽  
Building Materials ◽  
Radon Exhalation ◽  
Radon Exhalation Rates

Feasibility of a Defined Microflora Challenge Method for Evaluating the Efficacy of Foodborne Listeria monocytogenes Selective Enrichments

2000 ◽  
Vol 63 (8) ◽  
pp. 1064-1070 ◽  
Author(s):  
ANTHONY D. HITCHINS ◽  
R. E. DUVALL
Keyword(s):  
Listeria Monocytogenes ◽  
Evaluation Method ◽  
Test Sample ◽  
International Standards ◽  
Microbial Pathogens ◽  
Food Matrix ◽  
High Input ◽  
Isolation Methods ◽  
One Step ◽  
International Standards Organization

Comparison of isolation methods for microbial pathogens is complicated by the variable interference caused by the competitive microflora present in test samples such as foods. In principle, using measured amounts of a standard competitor in a defined surrogate food matrix might control the effect of variable interference. This possibility was investigated using Listeria monocytogenes and enrichment broths belonging to the acriflavine-nalidixate selective agent class. Triplicate test sample sets were prepared. Each set consisted of suspensions of variable levels of the standard competitor, Enterococcus faecium strain 111 (≈10 to 109 CFU/25 g), mixed with a low constant level (10 to 100 CFU/25 g) of L. monocytogenes. These test samples were enriched at 30°C for 48 h in different selective media and streaked onto selective isolation agars. The input CFU ratio (E. faecium/L. monocytogenes) that permitted a 50% end point L. monocytogenes recovery was 2.2 × 106 or higher for the Food and Drug Administration one-step enrichments and 0.8 × 106 for the International Standards Organization (ISO) two-step enrichment. These and other results show that this evaluation method is feasible with this class of enrichments. Interestingly, L. monocytogenes could be detected in enrichment cultures at high-input E. faecium/L. monocytogenes ratios even when the enriched samples were plated onto nonselective media. The pinpoint colonies of L. monocytogenes embedded in a confluent lawn of E. faecium 111 were detectable by their contrasting coloration in Henry obliquely transmitted illumination.

Setup and procedure for routine measurements of radon exhalation rates of building materials

2018 ◽  
Vol 112 ◽  
pp. 6-10 ◽  
Author(s):  
D. Al-Azmi ◽  
I.C. Okeyode ◽  
O.O. Alatise ◽  
A.O. Mustapha
Keyword(s):  
Building Materials ◽  
Radon Exhalation ◽  
Radon Exhalation Rates

scholarly journals Radon exhalation rates from common building materials in India: Effect of back diffusion

2016 ◽  
Vol 31 (3) ◽  
pp. 277-281
Author(s):  
Amit Kumar ◽  
Pal Chauhan
Keyword(s):  
Building Materials ◽  
Rice Husk Ash ◽  
Indoor Radon ◽  
Track Detector ◽  
Back Diffusion ◽  
Type Ii ◽  
Indoor Radon Concentration ◽  
Radon Exhalation ◽  
Brick Powder ◽  
Radon Exhalation Rates

A radon exhalation study for building materials was carried out by closed accumulator technique using plastic track detector LR-115 type-II, taking into account the effect of back diffusin. The back diffusion of radon into the materials causes an underestimate of free exhalation rates. The results showed that radon exhalation rates of soil, sand, brick powder, and crasher were found to be high as compared to rice husk ash, wall putty, and plaster of Paris. The radon exhalation rates from building materials varied from 0.45 ? 0.07 mBq/kgh to 1.55 ? 0.2 mBq/kgh and 3.4 ? 0.7 mBq/m2h to 28.6 ? 3.8 mBq/m2h as measured without considering back diffusion. The radon exhalation rates of building materials oblivious of back diffusion varied from 4.3 ? 0.8 mBq/m2h to 44.1 ? 5.9 mBq/m2h. The radon exhalation rates from building materials can be used for estimation of radon wall flux and indoor radon concentration. Thus, it is necessary to make correction in the measured exhalation rates by back diffusion.

Accurate measurement of the radon exhalation rate of building materials using the closed chamber method

2012 ◽  
Vol 32 (3) ◽  
pp. 315-323 ◽  
Author(s):  
Lei Zhang ◽  
Xing Lei ◽  
Qiuju Guo ◽  
Shanqiang Wang ◽  
Xinhua Ma ◽  
...  
Keyword(s):  
Building Materials ◽  
Radon Exhalation Rate ◽  
Exhalation Rate ◽  
Closed Chamber ◽  
Radon Exhalation ◽  
Chamber Method ◽  
Closed Chamber Method
Sign in / Sign up

Export Citation Format

Share Document