DETERMINATION OF NEUTRON EFFECTIVE DOSES IN WHOLE BODY POINT SOURCE EXPOSURES.

The objective of this work is to obtain fluence to effective dose conversion coefficients for neutron point sources, using the GEANT4 toolkit. These calculations aim to investigate the aspects of neutron transport in the human body through Monte Carlo simulation using the International Commission on Radiological Protection (ICRP) voxel phantoms, described in its publication 110. A benchmarking of the code was made for the case of monoenergetic plane parallel neutron beam in the antero-posterior (AP) irradiation geometry and organ absorbed dose conversion coefficients were compared with those found in the ICRP publication 116.

A Brazilian government external individual monitoring service: experience since 1972.

Instituto de Radioproteção e Dosimetria, a Brazilian government research institute, provides individual monitoring services since 1972. Its dosemeters are: film-based thorax for whole body photons, thermoluminescence dosimetry (TLD) albedo for whole body neutrons and TLD ring for extremity photons. About 6000 radiation workers are currently being monitored with film dosemeters in 256 different facilities in Brazil, most of them working in health-related activities.

Brazilian external occupational dose management system.

Brazil, a large country, with more than 120,000 workers under individual monitoring for ionising radiation, developed, more than 20 y ago, a centralised data bank for external occupational dose. This old database, however, presented some problems and does not satisfy any more Brazilian present needs, not allowing dose analysis reports, for example. Therefore, a new system that reduces manual tasks, provides system communication support, manages reports and improves data storage management is being developed.

Radiation protection for pregnant workers and their offspring: a recommended approach for monitoring.

Radiation protection of pregnant workers and their offspring is an issue that has been referenced in the literature by the International Commission on Radiological Protection (ICRP), the International Atomic Energy Agency (IAEA) and other international institutions. Several documents of the ICRP address the issue of the protection of the pregnant workers. The new ICRP recommendations refer to the control of working conditions of a pregnant worker, after declaration of pregnancy, such that it is unlikely that the additional dose to the fetus will exceed about 1 mSv during the remainder of pregnancy.

Nuclear medicine annual external occupational dose distribution: Rio de Janeiro, Brazil, year 2005.

Brazil has about 300 nuclear medicine services (NMS), 44 of them located in the state of Rio de Janeiro (RJ). Most nuclear medicine staff are routinely monitored for external dose. This paper makes a statistical analysis of all the RJ NMS annual external occupational doses in year 2005.