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Effect of a nuclear power plant in terms of radiatin burden
Vániš, Jiří ; Procházka, Zdeněk (referee) ; Belatka, Martin (advisor)
This text deals with ionizing radiation affecting nuclear power plant personnel and surrounding population. Irradiation limits of radiological industry personnel are also mentioned along with ways of protecting them and checks on absorbed ionizing radiation dose. In conclusion, a nuclear power plant, as a source of ionizing radiation, and its effects on contamination of water sources and gas vents are evaluated. The next part be engaged problematical of storage nuclear waste from the time, when is removed the nuclear waste from nuclear reactor, trough permanent storage.
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Effect of a nuclear power plant in terms of radiatin burden
Vániš, Jiří ; Procházka, Zdeněk (referee) ; Belatka, Martin (advisor)
This text deals with ionizing radiation affecting nuclear power plant personnel and surrounding population. Irradiation limits of radiological industry personnel are also mentioned along with ways of protecting them and checks on absorbed ionizing radiation dose. In conclusion, a nuclear power plant, as a source of ionizing radiation, and its effects on contamination of water sources and gas vents are evaluated. The next part be engaged problematical of storage nuclear waste from the time, when is removed the nuclear waste from nuclear reactor, trough permanent storage.
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Measurement of photons via electronic dosimeters for the acceleration of charged particles at the Institute of Physics ASCR in Prague.
ŽIDKOVÁ, Jana
The thesis is focused on summarizing the current issue of work with experimental lasers in the research center of Prague Asterix Laser System (PALS), which falls under the Institute of Physics and Institute of Plasma Physics. Experimental lasers used for experimental research in the field of powerful laser physics and laser-produced plasma. The main experimental facility PALS is a powerful pulsed laser system Asterix IV., The research center was purchased from the German Max Planck Institute for quadratic Optics in Garching near Munich for a symbolic 1 mark. Asterix is one of the three largest iodine lasers in Europe. Between the research programs being carried out on the experimental development of lasers include applications of plasma point sources of soft non-coherent radiation, development and application of laser plasma X-ray etc. Other facilities located in the research center include PALS laser system Ti - Sapphire power of 25 terawatts. In this system, a similar experiment was performed measuring photon film dosimeters. The experimental laser Asterix IV in the research center PALS have been no experiment with film or electronic dosimeters. This work deals with the possibility of using electronic personal dosimeters when working with lasers and detection sensitivity of the dosimeters, unlike other types of personal dosimeters. This was achieved by measuring the two independent measurements ongoing at the Asterix IV laser system. Possibilities of using electronic personal dosimeters for measuring the pulse field, even though they are designed to measure benefits only in the continuous field is particularly important for workers newly built ELI center in Prague. Center ELI will be the most modern laser equipment in the world. In it will be carried out the research and application projects involving the interaction of light with matter in intensity, which is about 10 times larger than the currently achievable. ELI will deliver ultrashort laser pulses lasting typically a few femtoseconds (10-15 fs) and produce power up to 10 PW. The ELI Center will be unlike PALS controlled area in which it is important to monitor external radiation workers. Therefore, the thesis is aimed at providing support for PALS measurement using electronic personal dosimeters Center ELI. We also compare the sensitivity of the most common types of personal dosimeters such as film and thermoluminescent dosimeters. In the theoretical part of the description and principle of laser Asterix IV. Furthermore, the definition of ionizing radiation and its species with a particular focus on gamma and X-rays. In this thesis remains missing definitions such as dosimetry, types of dosimeters, monitoring, radiation protection and value to it. In the methodology are then analyzed measurements that were carried out in two experiments using electronic personal dosimeters, film dosimeters and thermoluminescent dosimeters. Furthermore, also the deployment of the laser system, focusing mainly on the description of the interaction of the hall and the interaction chamber, where were measured. The methodology is also a series of photos of photos taken at the workplace PALS for easier orientation. In the results, the values of individual measurements recorded for better clarity in the tables and charts described. The discussion is focused on the confirmation of hypotheses. Are compared to results from electronic and film dosimeters and electronic dosimeters and termoluminescent. Results are based on one shot and statistically processed. In the event of a general summary of the work, it is recommended the use of electronic personal dosimeters to work with experimental lasers and supported the intention of the use of electronic personal dosimeters in the newly built Center ELI in Prague, mainly because of higher sensitivity than that with film and TLD and also for easier, faster, and economical evaluation of the benefits.
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Measuring of personal doses of radiodiagnostics workers with electronic personal dosimeter.
CHMELÍKOVÁ, Helena
Radiodiagnostics is a relatively young field of medicine the objective of which is imaging of anatomic structures and physiological and pathological processes in order to determine diagnoses or prognoses of diseases. For this purpose radiodiagnostics uses ionizing radiation with both its positive and negative effects. The effects are demonstrated also in healthy cells and healthy tissues of the human organism. A radiation protection system therefore establishes, among other things, limit doses to which individuals working with ionizing radiation may be exposed while performing their jobs. The received doses are kept under control by means of a dosimetric system. Essentially, there are two types of dosimeters: passive and active, i.e. electronic. The purpose of this thesis is to compare results from personal film dosimeters with results obtained from electronic dosimeters DMC 2000 XB made by Merlin Gerin and to determine whether electronic dosimeters are suitable for radiodiagnostics and whether they can replace film dosimeters. I performed the measurements at the radiodiagnostics ward of the hospital Nemocnice Sušice, o.p.s. X-ray assistants in the ward are routinely equipped with personal film dosimeters. In addition to their film dosimeters, they were given personal electronic dosimeters for a period of seven months. They were wearing both types of the dosimeters in compliance with the Decree issued by the State Office for Nuclear Safety (SÚJB) No. 307/2002 Coll., as amended, at the reference place, i.e. on the left upper part of the chest on their clothing. Measurements were conducted on five X-ray assistants and one additional personal electronic dosimeter was used to measure the natural background. I have used results from electronic personal dosimeters to evaluate the collective dose of all workers in the individual months, the total collective dose and the sum of dose equivalents in all months for the individual workers. The collective dose from dose equivalents Hp(10) was stable most of the time and in November and December it was slightly higher. This was due to a higher frequency of surgeries which required presence of an assistant with an X-ray device in the operating room. The highest sum of dose equivalents Hp(10) was found for the worker No. 1 due to his more frequent presence in the operating room. Although the X-ray workers take turns at the workplace regularly they perform their tasks at random. I can definitely exclude that the worker No. 1 was in any way different from the other workers - when it comes to radiation protection all X-ray assistants observe the same principles of radiation protection. For better understanding the thesis also includes information about working activities performed by X-ray assistants. Despite the fact that the measurements using electronic dosimeters several times indicated monthly values of personal dose equivalent Hp(10) higher than 0.1 mSv, the evaluation of the respective film dosimeters from the same period of time indicated values lower than 0.1 mSv or lower than 0.05 mSv. Subsequent investigations have shown that CSOD, s.r.o. is capable of measuring values = 0.01 mSv. The discrepancy between the measured results therefore does not come from the evaluation but from a lower sensitivity of the film dosimeter. The thesis also includes evaluation of advantages and disadvantages of both the types of personal dosimeters. Based on results of the measurements, evaluation of advantages and disadvantages of the two types of personal dosimeters and based on working activities of X-ray assistants I can conclude that the personal electronic dosimeter DMC 2000 XB made by Merlin Gerin is suitable for activities at the radiodiagnostics ward and that it may fully replace the film dosimeter.
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The use of personal dosimetry on nuclear power plants abroad
KAUCA, Michal
There is performed the analyse of the use of personal dosimetry on nuclear power plants abroad compared with the situation in Czech Republic in this work. There is made the quality compare the usage of particular kinds of personal dosimetry on basis of informations got from choice nuclear operations, and the compare it with the situation in Czech Republic. I chose the way of getting of data by e-mail. On basis of got informations I made the compare as was objective this work. By compare of situation in radiation protection was found, the used personal dosimeters abroad and in Czech Republic are the same type almost. Some states including Czech Republic go over to legalization of personal electronic dosimeter as primary instrument of radiation protection. The matter of interest is the situation in Slovakia, where is receded from this type of dosimeter as primary and they returned to the previous type of dosimeters. Another speciality are the authorised limits for radiation worker in controled zone also for pregnant women in Japan. It isn´t usual in other states. This work refers to influence of personal dosimetry over the level of radiation protection in nuclear establishment and also over the connection of safety disposal in personal dosimetry with approved legislative in choice states, over the necessity of the controle, the competence of personal and also the progressive research and development in personal dosimetry. It is necessary to see the radiation protection globally. The personal dosimetry will have been not only national problem but also international matter. The new development in the sphere of passive and electronic dosimeters up to the complete global concepts of control is operationed already today in many states and it is offered in the international market still more often.
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Development of system reduction and limitation of doses in persons working with sources of ionizing radiation and in inhabitants
TEPLÝ, Antonín
Development of system reduction and limitation of doses in persons working with sources of ionizing radiation and in inhabitants This dissertation discusses a system of limits and its development, i.e. how did the radiation dose limits change due to the safety of staff working with ionizing radiation and how did the limits of exposure of the population change. The introduction part of this dissertation deals with basic principles of radiation protection, namely with its optimization {--} with ALARA system. In the Current situation chapter there is a system of limits for reduction of radiation (Sec. 18 and 22 of the State Office for Nuclear Safety Decree No 307/2002 Sb.) and derived limits. The main part of this project focuses on monitoring of the practical development of the system of limits. In the Radiation Oncology Institute of the Faculty Hospital Na Bulovce (Ústav radiační onkologie Fakultní nemocnice Na Bulovce) archive I received data from the CSOD. I processed listing of both free-month and one-month doses received by the staff and I studied the way the doses decrease and mainly how does the number of personnel in whose cases the doses exceeded their limits decrease. I involved three most numerous groups of personnel. The first group consists of radiology assistants and analysts, the second group consists of medical doctors and physicists and the third group consists of medical nurses who were monitored only till 2003. The greatest decrease can be noticed since 2003 when the listings of radiation doses started being evaluated on monthly basis. I think that monthly evaluation of doses is a great landmark in the issue of protection of personnel involved with ionizing radiation. I transferred the data about these doses into several charts. I divided exceeded doses into individual scales and processed them statistically. There is a table in the discussion part of this dissertation work where even historical dose limits and dose equivalents are converted to mSv units (i.e. mSv/year) so that it would be possible to compare the limits. The process of radiation protection of the personnel in the Institute is also dealt with.
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