Occupational exposure in Greek industrial radiography laboratories (1996-2003)

OCCUPATIONAL EXPOSURE IN RADIATION APPLICATIONS IN INDIA: TRENDS AND DISTRIBUTION ANALYSIS

Occupational exposure data in radiation applications provide a good insight on the radiation risks to workers from occupational hazards, the safe practices adopted and in deriving methods to prevent possible radiation exposures. The analysis of occupational exposure may be used to provide regulatory guidance and more focused attention to improve the safety systems, thus improving the personnel and environment safety. In this study, occupational exposure from radiation applications during 2004-18 amounting to a total number of 1951 486 occupational dose data are collected and analysed using the statistical software package, SPSS. As recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation, four critical parameters viz., annual collective effective dose, average annual effective dose, individual dose distribution ratio and the annual collective dose distribution ratio for each practice are estimated. Using the trend observed for these parameters, it is predicted that occupational exposure in diagnostic radiology in the year 2023 would increase by 80% in total number of monitored with 76% increase in average collective dose and no significant change in average annual effective dose. In the same manner, nuclear medicine would see 28% of increase in radiation workers with the increase of 24% in collective dose with no significant change in average annual effective dose. Further, the reasons and area of regulatory focus for the different practices are discussed.

The impact of radiation protection training on the radiological safety and the related culture of exposed workers in Greece

The safe use of radiation sources presupposes the engagement of personnel adequately educated and trained on radiation protection and with the necessary safety culture. This is necessary in order to understand their responsibilities and perform their duties in the safest way for themselves, the public and the patients, where appropriate. The Greek Atomic Energy Commission (EEAE) provides education and training on radiation protection to scientists, technical personnel and members of emergency response teams as well as the recognition of the related programs. To fulfil its role, EEAE implements a strategy on education and training in radiation protection through the development of appropriate programs which take into account the national needs, as well as the national capabilities and resources. In this respect, 65 one and two day training seminars were organised in the period 2011-2017 which were attended by 3126 radiation workers (i.e. medical radiology and nuclear medicine technologists, industrial radiographers and outside workers). The present work demonstrates a quantified assessment of the impact of EEAE training activities on particular categories of radiation workers. The study indicates a reduction in H p(10) values as well as in the corresponding standard deviations of medical radiology technologists, nuclear medicine technologists, and industrial radiographers. A 48% decrease was also observed in the collective dose of medical radiology technologists with cumulative H p(10) values higher than the investigation level. Moreover, an important improvement of specific safety culture indicators, such as the percentage of non-returned personal dosemeters was noticed and presented.

DOSIMETRIC ASPECTS OF OPTIMIZATION OF PROTECTION IN IRAN INDUSTRIAL RADIOGRAPHY PRACTICE

According to the worldwide reports, industrial radiography is one of the highest risk radiation practices due to handling high activity sources. Therefore, an optimization of protection along with appropriate investigation level and/or dose constraint is required to achieve appropriate radiological safety. This research, presents some statistical aspects of this optimization using frequency distributions and percentiles of individual recorded dose of industrial radiographers from the years 2002 to 2016 in Iran. The results show that, considering an investigation level of 4 mSv for bimonthly monitoring periods, 3-7% of population of workers has been investigated during these years. Moreover, an overall reduction on average annual and collective doses is observed, despite of the relative increasing in the number of workers. Since the frequency of periodical recorded dose at lower dose range (e.g. <4 mSv) causes greater impacts on the reduction of collective dose than the higher ranges, a retrospective average dose of non-investigated workers can also be substitute with a constant value as a dose constraint. It can be concluded that all the past measures of regulatory body and attempts of the employers have been effective improving the radiological protection in this practice in Iran. However, establishing a dose constraint seems to be essential to continue and improve this optimization of protection.

A root cause analysis of the high occupational doses of industrial radiographers in Iran

The Iran Nuclear Regulatory Authority has investigated overexposure cases in industrial radiography over a period of three years. Radiographers with thermoluminescence dosimeter (TLD) records of more than 4 mSv in any 2 month routine monitoring period were asked to fill in a questionnaire explaining their points of view of the reasons for such relatively high doses. The responses showed that more than 50% of the radiographers did not agree with their recorded TLD doses, although the majority of the alternative explanations were weak. The main causes of overexposures were found to be difficult working conditions and ignoring safety principles while accidents or device failures were a minor contribution. Also, there was poor correlation between the TLDs and direct reading dosimeters worn by the radiographers, indicating that personal monitoring instructions were not being implemented appropriately.

Occupational exposure of medical radiation workers in Lithuania, 1950-2003

This study presents the summary of historical exposures, measurement practice and evolution of the recording of the individual doses of medical radiation workers during 1950-2003 in Lithuania. The aim of this study is to present occupational exposure of medical radiation workers in Lithuania since the earliest appearance period. Data from publications have been used for the earliest two periods prior to 1969; data from the archives of the largest hospitals, for the period 1970-1990 and data from Lithuanian Subdivision of Individual Dosimetry of Radiation Protection Center, for the period 1991-2003. The analysis of the data obtained from personal records allows to conclude that the average annual effective dose of Lithuanian medical radiation workers was greatly reduced in radiology, radiotherapy and nuclear medicine in all occupational categories from 1950 to 2003. During the last period 1991-2003 extremity doses clearly decreased and after 1994 were no longer present in Lithuania.