Design of an advanced TLD-based fixed nuclear accident dosimeter

Casson, W H; Mei, G T

doi:10.2172/10178185

Title: Design of an advanced TLD-based fixed nuclear accident dosimeter

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Abstract

A new system has been designed for use as a fixed nuclear accident dosimeter based upon the thermoluminescent dosimeter (TLD) system used for personnel dosimetry at US Department of Energy facilities managed by Martin Marietta Energy Systems, Inc. The system is made up of a small phantom consisting of two main parts measuring 20 x 20 x 5 cm and made from polymethylmethacrylate. A neutron-sensitive TLD card is placed in the center between the two pieces. Also, TLD cards in standard holders are mounted on the front and back of the phantom. A derivation is made of a linear combination of the responses from the TLD elements which results in calculation of the neutron fluence, absorbed dose, and dose equivalent. By using the right linear combinations, a crude spectrum can be estimated, which allows further calculation of the average fluence-to-dose-equivalent conversion factor. The response of the system was tested and found to be applicable for the evaluation of typical nuclear accident spectra, although considerable improvement can be made by the addition of a sulfur pellet. The system was also tested for angular dependence. In order to move the development of this system from the proof-of-principle to full application, the calculationmore »« less

Authors:: Casson, W H; Mei, G T

Publication Date:: Sun Aug 01 00:00:00 EDT 1993

Research Org.:: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:: USDOE, Washington, DC (United States)

OSTI Identifier:: 10178185

Report Number(s):: ORNL/TM-12300
ON: DE93019856; TRN: 93:019182

DOE Contract Number:: AC05-84OR21400

Resource Type:: Technical Report

Resource Relation:: Other Information: PBD: Aug 1993

Country of Publication:: United States

Language:: English

Subject:: 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 61 RADIATION PROTECTION AND DOSIMETRY; THERMOLUMINESCENT DOSEMETERS; DESIGN; REACTOR ACCIDENTS; PERSONNEL DOSIMETRY; US DOE; PHANTOMS; NEUTRONS; DOSE EQUIVALENTS; PERFORMANCE TESTING; 440102; 560101; RADIATION DOSEMETERS; DOSIMETRY AND MONITORING

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                    Casson, W H, and Mei, G T. Design of an advanced TLD-based fixed nuclear accident dosimeter.  United States: N. p., 1993. 
        Web.  doi:10.2172/10178185.

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                    Casson, W H, & Mei, G T. Design of an advanced TLD-based fixed nuclear accident dosimeter.  United States.  https://doi.org/10.2172/10178185

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                    Casson, W H, and Mei, G T. 1993.  
        "Design of an advanced TLD-based fixed nuclear accident dosimeter".  United States.  https://doi.org/10.2172/10178185.  https://www.osti.gov/servlets/purl/10178185.

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@article{osti_10178185,

  title        = {Design of an advanced TLD-based fixed nuclear accident dosimeter},

  author       = {Casson, W H and Mei, G T},

  abstractNote = {A new system has been designed for use as a fixed nuclear accident dosimeter based upon the thermoluminescent dosimeter (TLD) system used for personnel dosimetry at US Department of Energy facilities managed by Martin Marietta Energy Systems, Inc. The system is made up of a small phantom consisting of two main parts measuring 20 x 20 x 5 cm and made from polymethylmethacrylate. A neutron-sensitive TLD card is placed in the center between the two pieces. Also, TLD cards in standard holders are mounted on the front and back of the phantom. A derivation is made of a linear combination of the responses from the TLD elements which results in calculation of the neutron fluence, absorbed dose, and dose equivalent. By using the right linear combinations, a crude spectrum can be estimated, which allows further calculation of the average fluence-to-dose-equivalent conversion factor. The response of the system was tested and found to be applicable for the evaluation of typical nuclear accident spectra, although considerable improvement can be made by the addition of a sulfur pellet. The system was also tested for angular dependence. In order to move the development of this system from the proof-of-principle to full application, the calculation of the TLD resonse curves must be improved, additional measurements must be made, and the system must be tested in a simulated accident neutron field. The advantages of the new fixed dosimeter system are its simplicity, easy maintenance, and lower operational cost. The system uses standard TLD cards that are already in place throughout Energy Systems facilities. The TLD process personnel are famliiar with evaluating doses from TLDs and can provide information necessary to ensure timely and accurate assessment of exposures that may result from riticality accidents. Most of the quality control requirements are part of the existing personnel dosimetry system.},

  doi          = {10.2172/10178185},

  url          = {https://www.osti.gov/biblio/10178185},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Sun Aug 01 00:00:00 EDT 1993},

  month        = {Sun Aug 01 00:00:00 EDT 1993}

}

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