Study of the responses and calibration procedures of neutron and gamma area and environmental detectors for use in proton therapy.

07:00 EST 5th February 2019 | BioPortfolio

Summary of "Study of the responses and calibration procedures of neutron and gamma area and environmental detectors for use in proton therapy."

Ambient dose equivalent measurements with radiation protection instruments are associated to large uncertainties, mostly due to the energy dependence of the instrument response and to the dissimilarity between the spectra of the standard calibration source and the workplace field. The purpose of this work is to evaluate its impact on the performance of area and environmental detectors in the proton therapy environment, and to provide practical solutions whenever needed and possible. The study was carried out at the Centre Antoine Lacassagne (CAL) proton therapy site, and included a number of commercially available area detectors and a home-made environmental thermoluminescent dosimeter based on a polyethylene moderator loaded with TLD600H/TLD700H pairs. Monte Carlo simulations were performed with MCNP to calculate, first, missing or partially lacking instrument responses, covering the range of energies involved in proton therapy. Second, neutron and gamma spectra were computed at selected positions in and outside the CAL proton therapy bunkers. Appropriate correction factors were then derived for each detector, workplace location and calibration radionuclide source, which amounts to up to 1.9 and 1.5 for neutron and photon area detectors, respectively, and suggest that common ambient dose equivalent instruments might not meet IEC requirements. The TLD environmental system was calibrated in situ and appropriate correction factors were applied to account for the cosmic spectra. Measurements performed with this system from 2014 to 2017 around the installation were consistent with reference natural background dose data and with pre-operational levels registered at the site before the construction of the building in 1988, showing thus no contribution from the site clinical activities. An in situ verification procedure for the radiation protection instruments was also implemented in 2016 at the low energy treatment room using the QA beam reference conditions. The method presents main methodological, practical and economic advantages over external verifications.


Journal Details

This article was published in the following journal.

Name: Journal of radiological protection : official journal of the Society for Radiological Protection
ISSN: 1361-6498
Pages: 250-278


DeepDyve research library

PubMed Articles [28510 Associated PubMed Articles listed on BioPortfolio]

Development of the Environmental Radiation Survey Program and Its Application to In Situ Gamma-Ray Spectrometry.

An environmental radiation survey using a gamma-ray spectrometer is used to rapidly detect radioactive contamination over a wide area of ground that was released from nuclear events. For the successfu...

Efficiency calibration of HPGe detector in a PGNAA system for the measurement of aqueous samples.

In this work, a method was proposed for efficiency calibration of HPGe detector employed in a prompt gamma-ray neutron activation analysis (PGNAA) system for large aqueous sample analysis. Experimenta...

Impact of the newly proposed ICRU/ICRP quantities on neutron calibration fields and extended range neutron rem-counters.

In July 2017, the International Commission on Radiation Units and Measurements (ICRU) and the International Commission on Radiological Protection (ICRP) proposed the introduction of new operational qu...

A method for determining density based on gamma ray and fast neutron detection using a CsLiYCl detector in neutron-gamma density logging.

With the increasing demand for radioisotope-free operations, pulsed neutron-gamma density (NGD) has become increasingly important for logging-while-drilling (LWD) development. However, current NGD too...


Neutron fields produced by an accelerator-driven neutron source are generally mixed radiation fields that consist of fast neutrons and gamma rays. To estimate the biological effects of fast neutrons p...

Clinical Trials [6793 Associated Clinical Trials listed on BioPortfolio]

Boron Neutron Capture Therapy in Treating Patients With Melanoma

RATIONALE: Boron neutron capture therapy may selectively kill tumor cells without harming normal tissue. PURPOSE: Phase II trial to study the effectiveness of boron neutron capture therap...

In-hospital Neutron Irradiator (IHNI)-Based Boron Neutron Capture Therapy (BNCT) in the Treatment of Malignant Melanoma

Boron Neutron Capture Therapy (BNCT) has been used in the treatment of several types of malignant tumors, including malignant melanoma, high-grade gliomas, and advanced head and neck cance...

Use of a Gamma-IFN Assay in Contact Tracing for Tuberculosis in a Low-Incidence, High Immigration Area

After exposure to an active case of tuberculosis (TB), close contacts may be infected. They are then considered as having latent tuberculosis infection (LTBI). Detecting LTBI is the main g...

Boron Neutron Capture Therapy Following Surgery in Treating Patients With Glioblastoma Multiforme Removed During Surgery

RATIONALE: Boron neutron capture therapy may selectively kill tumor cells without harming normal tissue. PURPOSE: This phase I trial is studying the side effects and best dose of boron ne...

Safety and Efficacy of Inhaled Interferon Gamma-1b in Pulmonary MAC Infection

The purpose of this research study is to test the safety and effectiveness of inhaled Interferon gamma-1b (IFN-g 1b), when administered for 48 weeks and in combination with oral antibiotic...

Medical and Biotech [MESH] Definitions

The study of ENVIRONMENTAL POLLUTION and the toxic effects of ENVIRONMENTAL POLLUTANTS on the ECOSYSTEM. The term was coined by Truhaut in 1969.

A technique to study CELL MIGRATION in the INFLAMMATION process or during immune reactions. After an area on the skin is abraded, the movement of cells in the area is followed via microscopic observation of the exudate through a coverslip or tissue culture chamber placed over the area.

A constellation of responses that occur when an organism is exposed to excessive heat and other environmental stressors. Responses include synthesis of some proteins, repression of other proteins, and expression of new proteins. (From Segen, Dictionary of Modern Medicine, 1992)

Usually refers to the use of mathematical models in the prediction of learning to perform tasks based on the theory of probability applied to responses; it may also refer to the frequency of occurrence of the responses observed in the particular study.

A trace element with the atomic symbol B, atomic number 5, and atomic weight 10.81. Boron-10, an isotope of boron, is used as a neutron absorber in BORON NEUTRON CAPTURE THERAPY.

Quick Search


DeepDyve research library

Searches Linking to this Article