Radiation protection management in several X-ray installations of Narayangonj

Abstract

In Bangladesh, number of X-ray machine is increasing but the rate of increase accelerated with the recent economic expansion. Despite the low dose per examination, the magnitude of practice makes the diagnostic X-ray the dominant source of medical radiation exposures. It estimates that the average individual and collective doses to the world population from diagnostic medical X-ray exposure range from 0.3 to 2.2 mSv and 1.8 to 5 mSv respectively. The X-ray installations, therefore, deserve attention from population dose perspective. This study was under taken to survey the radiation protection management in several X-ray installations of Narayanganj district. To get a real picture of radiation protection management of a specific area this work is necessary. It will give us an assessment about the radiation protection condition of X-ray installations of our country. A questionnaire was used to collect the raw data about a specific X-ray installation. Questions were divided in some basic categories such as general information i.e. particulars of X-ray technicians, availability of protective equipment etc. and technical information i.e. types of X-ray unit, maximum kV and mA etc. Some technical observation such as availability of wal1ling signal, area of X-ray room etc. were also noted. Measurement of radiation exposure in each X-ray installation was calTied out at different locations of that specific installation by using a survey meter during typical X-ray exposure. Present study gives the information that only 12% radiation workers are trained and only 10% installations having a properly shielded control panel which is very important in considering radiation protection for X-ray operator. About 33% of the total installations have standard size X-ray room i.e. room with area above 16 m2 The lead apron, which is an important radiation protection equipment for the operator, is available in 83% installations. Only 28% installations have the entrance door with lead which is also essential for the protection of visitors standing out side the X-ray room. vii In the present study, skin entrance dose has been calculated by using two different \ empirical formulae. The variation of result has also been calculated. Then the organ dose calculation for different organs was done based on the skin entrance dose and Intemational Commission for Radiation Protection tissue weighting factor. The minimum value of organ doses were measured and for Gonads itis 4.33 flGy, for bone marrow, 4.33 flGy, for bone surface, 0.36 flGy, whereas, the maximum value of organ doses measured are for Gonads, 75.76 flGy, for bone sUlface, 4.87 flGy and for liver, 24.33 flGy. Study of this work thus compares well with the works which had already been done abroad. The layout of the X-ray room has also been drawn and the dose rate at various locations was measured by using a dose meter. These layouts should help to develop a standard layout plan for X-ray room. The results of this study will help us to understand the radiation protection management system of most of the X-ray installations of our country and to take necessary actions to implement the rules or regulations suggested for the radiation protection of the diagnostic X-ray installations. In coming years, there will be more clinics and govemment hospitals and it is therefore, suggested that in future, a more comprehensive study be carried out for dose absorbed by patients undergoing radiological investigations, the occupational workers, the public at. large (for example, relati ves accompanying the patients). It wiII' then give a more general picture of the radiation protection management in X-ray installations. However, the results presented in this work should partly serve as base line to establish a full-fledged radiation protection procedure for our country.