Articles

Determination of Scatter Radiation Round Three Different Models of Mammography Unit

/in /by

Purpose: this study was carried out to determine the amount of scatter radiation around three different models of digital mammography units may contribute to shielding calculations.

Objectives: measuring and comparing for scattered radiation at four orientations (4 x 90o=360o) round three mammography models.

Materials and methods: RADOS (RDS-120 Universal Survey Meter) device was used to measure scatter radiation at four orientations round three types of mammography digital models NM-GA, Liyum, and Mammomat. These orientations are backward, forward, left lateral, and right lateral. All measurements are taken in Craniocaudal projection.

Results: backward orientation has highest and right lateral has lowest intensity of scatter radiations when three models of digital mammography were used. Mammomat model with backward orientation was at highest 6.5μSv of intensity and NM-GA model at lowest intensity of 1.1 μSv from right lateral orientation.

Conclusions: The obtained measurements of scatter radiation at four different orientations may be used in a shielding calculation when NM-GA, Liyum, and Mammomat of mammography models are used.

Measurement of Background Ionizing Radiation in Kogi State, Nigeria

/in /by

Radiation is said to be energy that is in motion and manifests itself everywhere we look in the form of waves or particles which can either useful or dangerous. Since radiation has always existed in the environment since the earth’s origin, daily exposure to varied levels of ionizing radiation is inevitable for humans. Therefore, environmental radioactivity measurements are crucial for measuring the background radiation level caused by naturally occurring radioactive sources with terrestrial and cosmic origins because of these effects on living beings. The aim of this paper is to measure and record the background radiation of various locations evenly distributed across the twenty-one (21) local government areas of Kogi State and use the measured value to produce a reliable and easily accessible background radiation contour map for Kogi State using ArcGIS 10.3. Using a portable RDS-31 Multi-survey meter, the dose rate of background ionizing radiation (BIR) was measured in μSv/hr and the result shows that Ankpa LGA has the lowest mean readings of 0.096 μSv/hr and 0.1682 mSv/yr for the annual equivalent dose rates. Yagba East had the highest mean reading of 0.2300μSv/hr and highest annual equivalent dose rates of 0.4030mSv/yr. The result shows that eventhough the AEDE are greater than the 0.07mSv/yr global average value, however they are all below the ICRP’s recommended permitted limits of 1.00mSv/yr. This demonstrates that there are no immediate radiological health effects on the general people as a result of BIR exposure in the examined locations. It is recommended that the various human activities that raise BIR levels in the regions should be reduced and that activity concentrations of natural radionuclides and BIR levels in the state be periodically assessed.