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With technological advances in several research areas of science, it is becoming increasingly common to use computer programs to solve problems. Some of these programs are based on statistical analysis and simulation of reality, such as the Monte Carlo Method (MC). The MC is a statistical tool widely used in different areas of knowledge, as a resource for simulating events that involve from financial assessments to the interaction of radiation with matter. Thereby, surveys with radiation sources, for example, are constantly evolving to study the question of radiation protection. In this sense, this paper has as main objective to verify the relevance of the MC for the area of radiation protection, analyzing the studies that apply the method in the Postgraduate Program (PPG) in Radiation Protection and Dosimetry of Institute of Radiation Protection and Dosimetry (IRD). This is because it is understood thatthrough the application of Scientific Knowledge Management (SKM) the construction of knowledge happens through an exchange of scientific information, that is, exchange of relevant contents that help in the preservation of knowledge.In this sense, a bibliometric analysis of the dissertations and theses deposited in Brazilian bank was made using the search term "Monte Carlo" and its respective programs (PENELOPE, GEANT4, EGSnrc, MCNP and Visual Monte Carlo), to be found in the title, abstract or keywords. With the identification of works carried out in all areas of concentration of the PPG, it is understood that the MC is extremely relevant for studies in the area of radiation protection.

For the dosimetric evaluation of extremities and crystalline of workers inserted in Positron Emission Tomography procedures using the 18F-FDG radiopharmaceutical, a geometric phantom of the forearm and hand with the geometric phantom ADAM was implemented in Monte Carlo Geant4 code. Equivalent Dose values were obtained in 45 different points - between dominant, non-dominant and crystalline hands - for radiopharmaceutical administration procedure, with the use of injection syringe shielding. The data obtained through the simulation were analyzed according to dose limits established by the CNEN standard NN-3.01 of 2014.

O uso da técnica de modelagem matemática pelo método de Monte Carlo (MC) utiliza funções probabilísticas e números "aleatórios" para a realização de cálculos que simulam sistemas físicos, como o transporte de partículas radioativas. A determinação das primeiras e segundas camadas semiredutoras para um espectro determinado e uma distância pré-definida testou a verificou as vantagens e desvantagens de cada código na resolução de uma tarefa comum. Os resultados foram coerentes, mas discrepantes entre si entre 2,5 e 6,0 %, concluindo que os quatro códigos são poderosos e de fácil utilização, requerendo pouco conhecimento de linguagem computacional, inicialmente.

Anualmente, diversos radiofármacos são utilizados em mais de 50 procedimentos clínicos diferentes em todo o Brasil. Sendo assim, profissionais inseridos nas diversas práticas de Medicina Nuclear que envolvem atividades ligadas a radio-emissores de alta energia representam um grupo de maior exposição à radiação e justificam esforços permanentes na otimização de riscos radiológicos. A utilização de técnicas avançadas de monitoração representa um importante subsídio para a avaliação da exposição ocupacional em instalações e a consequente redução das doses individuais. Neste trabalho foi feita a implementação de um fantoma de mão e antebraço em código Geant4, para a avaliação da exposição ocupacional de extremidades de trabalhadores que realizam práticas de Medicina Nuclear. O modelo de simulação oferecido pelo Geant4 inclui um conjunto completo de recursos, com a reconstrução de trajetórias, geometrias e modelos físicos. Para este trabalho, os valores calculados em simulação são comparados com as taxas medidas por dosímetros termoluminescentes (TLDs) em fantoma físico REMAB®. A partir da análise dos dados obtidos através da simulação e experimentação, dentre os 14 pontos estudados, observou-se uma discrepância de até 8,2% dos valores de kerma encontrados. O fantoma geométrico implementado em código de Monte Carlo Geant4 foi devidamente validado e poderá ser usado, posteriormente, para a avaliação de doses em extremidades.

Fluence to dose equivalent conversion coefficients provide the basis for the calculation of area and personal monitors. Recently, the ICRP has started a revision of these coefficients, including new Monte Carlo codes for benchmarking. So far, little information is available about neutron transport below 10 MeV in tissue-equivalent (TE) material performed with Monte Carlo Geant4 code. The objective of this work is to calculate neutron fluence to personal dose equivalent conversion coefficients, Hp (10)/ϕ, with Geant4 code. The incidence of monoenergetic neutrons was simulated as an expanded and aligned field, with energies ranging between thermal neutrons to 10 MeV on the ICRU slab of dimension 30 x 30 x 15 cm3, composed of 76.2% of oxygen, 10.1% of hydrogen, 11.1% of carbon and 2.6% of nitrogen. For all incident energy, a cylindrical sensitive volume is placed at a depth of 10 mm, in the largest surface of the slab (30 x 30 cm2). Physic process are included for neutrons, photons and charged particles, and calculations are made for neutrons and secondary particles which reach the sensitive volume. Results obtained are thus compared with values published in ICRP 74. Neutron fluence in the sensitive volume was calculated for benchmarking. The Monte Carlo Geant4 code was found to be appropriate to calculate neutron doses at energies below 10 MeV correctly.