When the ICRP updated their recommended limits for eye dose, they ignited a renewed interest in eye dosimetry. Especially, how the updated eye dose estimates affect current regulations and what that would mean to a radiation worker. Radiation workers are commonly required to wear leaded eyeglasses to reduce their dose...
:
_____________________________________________________________________________________
David M. Hamby
Abstract:
When the ICRP updated their recommended limits for eye dose, they
Compliance with 10CFR 20.101 requires that exposure to the skin be assessed at a depth of 0.007 cm over 10 cm² area. This depth generally corresponds to the interface between the epidermal and dermal layers of the skin. The Nuclear Regulatory Commission states the criteria for evaluating skin dose from...
CR-39 foils were irradiated as part of nuclear accident dosimetry experiments using the Godiva reactor at the Nevada National Security Site and the Caliban and Prospero reactors at the Valduc Centre for Nuclear Studies in France. The irradiated foils were chemically etched using the standard Lawrence Livermore National Laboratory process...
Fortuitous dosimeters are radiosensitive objects carried by an individual who was exposed to radiation. These objects can be analyzed some time after exposure and the results can be used to aid in calculating radiation fields and doses received by individuals. Items that make good fortuitous dosimeters are those that are...
'Hot particle' skin dosimetry calculations are commonly performed using homogeneous dose-point kernels (DPK) in conjunction with scaling and backscatter models to account for non-homogeneous geometries. A new scaling model for determining the actual DPK for beta-particles transmitted by a high-Z source material has been developed. The model is based on...
The Department of Nuclear Engineering at Oregon State University has recently introduced a neutron radiography facility (OSNRF). The facility is dependent on a neutron source established by the OSU TRIGA® Reactor (OSTR). It was unknown how accurately a computerized model of the OSTR in conjunction with the OSNRF could represent...
The purpose of this research was to develop and test a radiation detector to perform beta dosimetry and spectroscopy. The detector utilizes plastic scintillator volumes to produce scintillation light in proportion to the amount of energy deposited in them, and a large-area avalanche photodiode to convert the light to electrical...
Internal dosimetry is challenging and relies on estimates using MIRD or ICRP biokinetic models. To address this, we looked at gene expression analysis in whole blood from radiotherapy patients. Patients with relapsed or refractory neuroblastoma who received ¹³¹I-mIBG at UCSF were used to correlate internal ionizing radiation (IR) dose with...
Internal dosimetry models show a representation of how radionuclides move through the body. This study takes a look at radiation wounds by modelling a puncture wound to the hand using Microshield software. An analysis of these models provides a triangulation method that could be used to investigate wound characteristics, as...
Current state-of-the-art environmental, clinical, and in-vivo radiation sensing systems utilizing various inorganic and tissue-equivalent plastic scintillators are not user friendly, suffer from electron-beam-generated noise, and are difficult to deploy successfully for real-time dosimetry. A robust, real-time detection system using different scintillating materials coupled to solid-state detectors by optical fibers is...
This study investigated gel dosimetry with X-ray CT imaging as a possible means for extracting dose information from a 3D gel dosimeter. Currently Optical CT and MRI are the popular means of dose extraction, but X-ray CT imaging has the advantage of being more convenient and cost effective. The dosimetric...
Eye plaque brachytherapy is an established technique for the treatment of ocular melanoma that allows for the preservation of the affected eye as well as visual function. A common treatment planning system for eye plaque procedures, Plaque Simulator (PS), assists physicists in calculating the radiation dose to the tumor and...
In the last decade regulatory bodies have begun to implement standards to protect populations of non-human biota (NHB) from the consequences of radiation exposure. This is a departure from previous regulatory frameworks which were concerned only with protecting man. The implementation of these new standards has started an ongoing discussion...
Radiation protection has historically been from a human protection approach, therefore many studies have neglected the potential dose contribution from the gastrointestinal tract (GIT) in animal studies. The International Commission on Radiological Protection (ICRP) utilized simplified geometric shapes with Dose Conversion Factors (DCF) based on homogenized models for the trout...
The U.S. Department of Energy (DOE) Order 458.1 states that the compliance with the DOE annual dose limit of 1 mSv (100 mrem) to a member of the public may be demonstrated by calculating dose to the maximally exposed individual (MEI) or to a representative person. Historically, the MEI concept...
As the field of radiation therapy evolves new treatment techniques will be
established. An example of an evolving treatment technique is respiratory gated
radiation therapy (RGRT). Research and studies have shown that RGRT can be used
to account for tumor motion as a result of respiratory motion. With evolving
technology...
A system for radiological dosimetry for nonhuman biota developed by International Commission on Radiological Protection (ICRP) relies on calculations that utilize the Monte Carlo simulations of simple, ellipsoidal geometries with internal radioactivity distributed homogeneously throughout. In this manner it is quick and easy to estimate whole-body dose rates to biota....
Two methods of radiation dose assessment were evaluated for the Cs-137 in soil ⇒ leafy vegetable ⇒ human consumption exposure pathway at three fictitious contaminated sites in California, Colorado, and Florida. An annual dose equation was developed and per USEPA risk assessment guidelines, traditional, single point annual dose estimates were...