Influence of radiotherapy room shielding on ambient dose equivalent due to photons H*(10)p and neutrons H*(10)n in the patient's plane.

This study discusses a computer simulation for the equivalent ambient dose due to photons, H*(10)p, and neutrons, H*(10)n, in the patient's plane undergoing radiation therapy. A standard radiotherapy room with an additional shielding made by one lead or steel tenth-value layer was considered. A Varian 2100/2300 C/D linear accelerator head operating at 18 MV was modeled.

Brazilian regulatory authority contribution to the shielding dimensioning model of radiotherapy rooms proposed by the NCRP 151.

The National Council on Radiation Protection and Measurements (NCRP) Report No. 151 is an essential document for bunker design commonly applied for radiotherapy treatment rooms. This document is used as a reference by several countries, including Brazil.

Modeling of a neutron irradiator using Monte Carlo.

The Nuclear Engineering Department of the Military Institute of Engineering (SE/7-IME) is designing and simulation a neutron irradiator with 1 Ci of Am-Be source. The objective of this irradiator is to generate a flux of neutrons to be used in research and teaching maintaining, for purposes of radiological protection, the rate of ambient dose equivalent, H*(10), below 10 μSv/h at 30 cm from the surface. This paper presents the proposed irradiator, values of H*(10) at different distances from the irradiator and the neutron flux in different points of the beam irradiation, all calculated using the MCNPX code.

Shielding implications on secondary radiation doses in prostate cancer treatment.

Medical linear accelerators (linacs) require a physical structure designed to provide adequate structural support which ensures the safety of patients, operators and the general public. During a radiotherapy session, healthy tissues are exposed to radiation, even with these safety guarantees. This unwanted exposure may increase the likelihood of developing secondary cancer.