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Exposure levels to staff in interventional radiology (IR) may be significant and appropriate assessment of radiation doses is needed. Issues regarding measurements using physical dosemeters in the clinical environment still exist. The objective of this work was to explore the prerequisites for assessing staff radiation dose, based on simulations only. Personal dose equivalent, Hp(10), was assessed using simulations based on Monte Carlo methods. The position of the operator was defined using a 3D motion tracking system. X-ray system exposure parameters were extracted from the x-ray equipment. The methodology was investigated and the simulations compared to measurements during IR procedures. The results indicate that the differences between simulated and measured staff radiation doses, in terms of the personal dose equivalent quantity Hp(10), are in the order of 30–70 %. The results are promising but some issues remain to be solved, e.g. an automated tracking of movable parts such as the ceiling-mounted protection shield.

Este estudo trata dos efeitos da radiação gama de Co-60 sobre papéis atingidos por um sinistro. Sete livros de arquivo corrente do séc. XXI, recuperados de enchente e que apresentaram infestação biológica, foram selecionados como amostras para a investigação da irradiação empregada como agente de desinfestação. Partindo da identificação dos principais gêneros de fungos presentes no material para determinar as doses empregadas, estudou-se os efeitos da radiação nas propriedades do papel e nas manchas de lama e de fungos. Foram consideradas doses de radiação gama compatíveis com a possibilidade de repetição do tratamento, pois acervos tratados não ficam imunes a novas infestações e as doses são cumulativas. Importante observar o limite de dose que os suportes documentais e bibliográficos suportariam, sem que ocorram danos, em caso de um novo tratamento. This study addresses the effects of Co-60 gamma radiation on paper. Seven books of registry office archives from 21 century, recovered from flood and that presented biological infestation were selected as samples to investigate the irradiation used as fungal infection treatment. Starting with the identification of the main fungi genera present in the material to determine the doses employed, some of the radiation effects on paper properties were studied as well as on mud and fungus stains. The gamma radiation doses compatible with the possibility of repeated treatment were also observed, because treated collections are not immune to new infestations by microorganisms and the doses are cumulative. It is important to consider the dose limit which documentary and bibliographic material could support without damages in case of a new irradiation treatment.