| Autor: |
Diana D. Duarte, João Cardoso, Luís Santos, Carlos Oliveira, Lina Vieira |
| Jazyk: |
English<br />Spanish; Castilian<br />Portuguese |
| Rok vydání: |
2015 |
| Předmět: |
|
| Zdroj: |
Saúde & Tecnologia, Vol 0, Iss 8, Pp 18-23 (2015) |
| Druh dokumentu: |
article |
| ISSN: |
1646-9704 |
| DOI: |
10.25758/s&t.v0i8.514 |
| Popis: |
Introduction – A radioactive contamination needs to be quantified in case it eventually occurs. Therefore it is necessary to ensure that the operating conditions of a surface contamination monitor are characterized by determining its detection efficiency. This experimental study aims to determine the detection efficiency of a contamination monitor and evaluate the distance and surface emission rate influence on the detection efficiency. Methodology – A contamination monitor Thermo Mini 900E was tested with reference radiation sources of Carbon – 14 (C-14), Cesium – 137 (Cs-137), Strontium – 90 (Sr-90), Chlorine – 36 (Cl-36) and Americium – 241 (Am-241) with its emission rate traced to the Physikalish Technischen Bundesanstalt (PTB). Sources of Sr-90 and C-14 with two different emission rates for each one and distances of 1 to 20mm were used to study its influence in the detection efficiency. Results – With the increasing of distance, the detection efficiency decreases. The most energetic radiation sources have higher detectionefficiency, boasting a 15% decrease over 20mm whereas the sources bearing a smaller efficiency decrease 10%. No influence of the surface emission rate in the detection efficiency was verified. Conclusion – Thus, it is concluded that the detection efficiency of a contamination monitor is dependent of the distance between it and the contamination as well as the type and energy of the radioisotopes present in the contamination. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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