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Radiation Survey Meters in Hospitals: Technology, Challenges, and a New Approach
White paper Radiation survey meters in hospitals: technology, challenges, and a new approach This white paper introduces a new radiation sur- essary environmental radiation in hospitals. To vey meter for the hospital segment: the RaySafe lower the risks of unwanted radiation-induced 452. First, the need for survey meters in hospi- effects, the goal is to minimize the exposure to tal environments is described. This is followed unnecessary radiation, both for patients and staff. by an introduction to common survey meter To be able to take the correct measures, it is es- technologies to illustrate their possibilities and sential to know the properties of the radiation in delimitations. Next, some difficulties with survey terms of energy range, dose rate, type of radia- meter measurements in hospitals are identified tion, and more. This is where radiation survey and discussed. Finally, the technology inside the meters are needed. RaySafe 452 is presented to summarize how the instrument addresses the identified issues. Figure 1 illustrates some measurement scenarios and demonstrate the wide range of measurement 1. Why radiation survey meters are need- needs in hospitals. Table 1 gives an overview of ed in hospitals the main areas of application of survey meters in hospitals, with quantities, units, and typical Ionizing radiation is not visible to the human eye. energy ranges of the radiation. It does not smell or make a noise, and you cannot feel it. In the complex and busy environment of a hospital, how can you ensure that patients and staff are not exposed to more ionizing radiation than necessary? Ionizing radiation is utilized for different purposes in medical procedures, with the three main areas being diagnostic imaging, nuclear medicine, and radiotherapy. -
Appendix B: Recommended Procedures
Recommended Procedures Appendix B Appendix B: Recommended Procedures Appendix B provides recommended procedures for tasks frequently performed in the laboratory. These procedures outline acceptable methods for meeting radiation safety requirements. The procedures are generic in nature, allowing for the diversity of research facilities, on campus. Contamination Survey Procedures Surveys are performed to monitor for the presence of contamination. Minimum survey frequencies are specified on the radiation permit. The surveys should be sufficiently extensive to allow confidence that there is no contamination. Common places to check for contamination are: bench tops, tools and equipment, floors, telephones, floors, door handles and drawer pulls, and computer keyboards. Types of Contamination Removable contamination can be readily transferred from one surface to another. Removable contamination may present an internal and external hazard because it can be picked up on the skin and ingested. Fixed contamination cannot be readily removed and generally does not present a significant hazard unless the material comes loose or is present large enough amounts to be an external hazard. Types of Surveys There are two types of survey methods used: 1) a direct (or meter) survey, and 2) a wipe (or smear) survey. Direct surveys, using a Geiger-Mueller (GM) detector or scintillation probe, can identify gross contamination (total contamination consisting of both fixed and removable contamination) but will detect only certain isotopes. Wipe surveys, using “wipes” such as cotton swabs or filter papers counted on a liquid scintillation counter or gamma counter can identify removable contamination only but will detect most isotopes used at the U of I. Wipe surveys are the most versatile and sensitive method of detecting low-level removable contamination in the laboratory. -
The Design and Construction of an Ionization Chamber to Measure Background Radiation
AN ABSTRACT OF THE THESIS OF KENNETH EARL WEAVER for theMaster of Science (Name of Student) (Degree) in General Science (Radiological Physics) presented on August 19, 1968 (Major) (Date) Title: THE DESIGN AND CONSTRUCTION OF AN IONIZATION CHAMBER TO MEASURE BACKGROUND RADIATION Redacted for privacy Abstract approved: John P. Kelley An ionization chamber was constructed, using a fiberglass wall sphere, for the purpose of measuring background radiation.The system consists of the fiberglass wall chamber, 38.85 liters in volume, air filled, not sealed, used in conjunction with a precision capacitor, nulling voltage supply and electrometer.It was calibrated against a Shonka, 16.5 liter, muscle-equivalent, sealed ionization chamber in conjunction with a Shonka electrometer. Measurements made over a period extending from July 22 to July 29, 1968 in a second floor laboratory (X-ray Science and Engi- neering Laboratory, Oregon State University) with the fiberglass chamber yielded a mean dose rate of 7.96± 0.21 p. rads/hr.Meas- urements made over the same period with the Shonka system yielded a mean dose rate of 7.73 0.07 y, rads/hr. The Shonka system was also used to measure background radiation as a function of time from December 14, 1967 to June 10, 1968.The mean value obtained over this period was 7.73 ± 0.10 11 rads/hr. The Design and Construction of an Ionization Chamber to Measure Background Radiation by Kenneth Earl Weaver A THESIS submitted to Oregon State University in partial fulfillment of the requirements for the degree of Master of Science June 1969 APPROVED: Redacted for privacy Associate Professor of Electrical Engin4ring in charge of major Redacted for privacy -Chairman of the Dp-partment of Gene/''al ScienyCe Redacted for privacy Dean of Graduate School Date thesis is presented August 19, 1968 Typed by Carolyn Irving for Kenneth Earl Weaver ACKNOWLEDGMENT The author wishes to express hissincere appreciation to Mr. -
Characterization of a Homemade Ionization Chamber for Radiotherapy Beams
Applied Radiation and Isotopes 70 (2012) 1291–1295 Contents lists available at SciVerse ScienceDirect Applied Radiation and Isotopes journal homepage: www.elsevier.com/locate/apradiso Characterization of a homemade ionization chamber for radiotherapy beams Lucio P. Neves a,n, Ana P. Perini a, Gelson P. dos Santos a, Marcos Xavier a, Helen J. Khoury b, Linda V.E. Caldas a a Instituto de Pesquisas Energe´ticas e Nucleares (IPEN-CNEN/SP), Comissao~ Nacional de Energia Nuclear, Av. Prof. Lineu Prestes 2242, 05508-000 Sao~ Paulo, Brazil b Universidade Federal de Pernambuco, Departamento de Energia Nuclear, Av. Prof. Luiz Freire 1000, 50740-540 Recife, Brazil article info abstract Available online 30 November 2011 A homemade cylindrical ionization chamber was studied for routine use in therapy beams of 60Co and Keywords: X-rays. Several characterization tests were performed: leakage current, saturation, ion collection Cylindrical ionization chamber efficiency, polarity effect, stability, stabilization time, chamber orientation and energy dependence. Radiotherapy All results obtained were within international recommendations. Therefore the homemade ionization Calibration procedures chamber presents usefulness for routine dosimetric procedures in radiotherapy beams. & 2011 Elsevier Ltd. All rights reserved. 1. Introduction In order to contribute with the calibration procedures at LCI, in this work a homemade ionization chamber, designed and devel- Radiotherapy is well known and widely used in oncological oped at LCI, for calibration procedures in 60Co beams was treatment practice. Nowadays, a lot of research has been done in characterized. order to improve the treatments involving radiotherapy. These The operational tests were: leakage current, saturation, ion improvements include organ-sparing treatments and local control collection efficiency, polarity effect, stability, stabilization time, of the dose delivery, resulting in a reduction of the patient dose chamber orientation and energy dependence. -
Low-Cost Radon Detector with Low-Voltage Air-Ionization Chamber
sensors Article Low-Cost Radon Detector with Low-Voltage Air-Ionization Chamber Filip Studniˇcka 1,†, Jan Štˇepán 2,† and Jan Šlégr 1,∗,† 1 Department of Physics, Faculty of Science, University of Hradec Králové, Rokitanského 62, 500 03 Hradec Králové, Czech Republic 2 Center of Advanced Technology, Faculty of Science, University of Hradec Králové, Rokitanského 62, 500 03 Hradec Králové, Czech Republic * Correspondence: [email protected]; Tel.: +420-493-33-2773 † These authors contributed equally to this work. Received: 20 July 2019; Accepted: 25 August 2019; Published: 28 August 2019 Abstract: This paper describes the design of a low-cost radon detector that can easily be fabricated in large quantities for the purposes of earthquake prediction. The described detector can also be used for monitoring radon levels in houses because high radon levels pose a great health risk. A very simple air-ionization chamber for alpha particles was used, considering the experimental results. Chamber current-sensing circuitry is also suggested, and an Internet of Things (IoT) sensor grid is described. The main advantages of this detector are the low cost, low power consumption, and complete elimination of high-voltage power sources. The minimum detectable activity achieved with the proposed detector for one measurement was around 50 Bq · m−3, with time of measurement comparable to that featured on commercial devices, while the price of the described detector is one order of magnitude lower. Keywords: charge-carrier processes; ionizing radiation sensors; wireless sensor networks 1. Introduction Earthquake prediction (a branch of seismology concerned with the specification of the time, location, and magnitude of future earthquakes [1]) uses several physical parameters to assess the probability of an impending earthquake. -
Radiation Glossary
Radiation Glossary Activity The rate of disintegration (transformation) or decay of radioactive material. The units of activity are Curie (Ci) and the Becquerel (Bq). Agreement State Any state with which the U.S. Nuclear Regulatory Commission has entered into an effective agreement under subsection 274b. of the Atomic Energy Act of 1954, as amended. Under the agreement, the state regulates the use of by-product, source, and small quantities of special nuclear material within said state. Airborne Radioactive Material Radioactive material dispersed in the air in the form of dusts, fumes, particulates, mists, vapors, or gases. ALARA Acronym for "As Low As Reasonably Achievable". Making every reasonable effort to maintain exposures to ionizing radiation as far below the dose limits as practical, consistent with the purpose for which the licensed activity is undertaken. It takes into account the state of technology, the economics of improvements in relation to state of technology, the economics of improvements in relation to benefits to the public health and safety, societal and socioeconomic considerations, and in relation to utilization of radioactive materials and licensed materials in the public interest. Alpha Particle A positively charged particle ejected spontaneously from the nuclei of some radioactive elements. It is identical to a helium nucleus, with a mass number of 4 and a charge of +2. Annual Limit on Intake (ALI) Annual intake of a given radionuclide by "Reference Man" which would result in either a committed effective dose equivalent of 5 rems or a committed dose equivalent of 50 rems to an organ or tissue. Attenuation The process by which radiation is reduced in intensity when passing through some material. -
Ionization Chamber Type Survey Instruments
Chapter 5: Instrumentation Objectives: • Summarize the advantages and disadvantages of the different types of devices used to monitor individuals for radiation exposure. • Describe the principal advantages and disadvantages of air ionization chamber type survey instruments. • Describe the principal advantages and disadvantages of Geiger-Müller (GM) type survey instruments. SAT Chapter 5 - Instrumentation 2 Objectives: • Describe the important characteristics of any radiation monitoring instrument and why these characteristics are important for obtaining accurate results. • Select the appropriate survey instrument for a task, and be able to ensure its proper operation and be able to interpret the results obtained. SAT Chapter 5 - Instrumentation 3 Overview: • Humans cannot detect ionizing radiation with any of our senses. But, we need to know: – Is ionizing radiation present? – Are we receiving dose from ionizing radiation? – How much dose have we received (mrem)? – Is there contamination present? • We use instruments which respond to ionizing radiation. The type of instrument needed depends on the type and levels of radiation that are present. • Radiation detectors respond to ionizations or excitations created by radiation interaction with the detector media. Detectors can either be gas-filled or solid materials. SAT Chapter 5 - Instrumentation 4 Instrumentation Gas-filled instruments for detecting ionizing radiation utilize the concept that radiation interaction with atoms can cause ionizations. The ions are collected and measured. This is used to provide information on the presence of radioactive material (contamination) or the dose rate in an area. Hi + Volt - Ionizing Radiation (MEDIUM) SAT Chapter 5 - Instrumentation 5 IONIZATION CURVE 1015 I II III IV V VI 1012 Proportional 109 Continuous Geiger- Discharge Müller 106 α # of Ion Pairs Collected Pairs Ion of # 103 β 0 0 200 400 600 800 1000 1200 1400 1600 Applied Voltage, V SAT Chapter 5 - Instrumentation 6 Ionization Chamber Ionization chambers measure the ionization of air. -
Radiation Dosimetry
Radiation Dosimetry AGEN-698 Advances in Food Engineering Introduction Radiation dosimetry is the branch of science that attempts to quantitatively relate specific measurement in a radiation field to chemical and/or biological changes that the radiation would produce in a target Radiation When radiation interact with matter it produces: Excited and ionized atoms and molecules A large number of secondary electrons Exposure It is defined for gamma and X- rays in terms of the amount of ionization they produce in air Units: roentgen [R] – 1 R = 2.58x10-4 C/kg ∆Q is the sum of all charges of one sign produced in air when ∆Q all the electrons liberated by Exposure = photons in a mass ∆m of air ∆m are completely stopped in air Applies only to electromagnetic radiation and the mass and roentgen refer only to air Absorbed dose The energy absorbed per unit mass from any kind 1J 107 erg of ionizing radiation in 1Gy ≡ = = any kind of matter kg 103 g Traditional unit: rad = erg = 104 = 100rad 100 erg/g g New SI unit: gray (Gy) Absorbed dose is often referred to simply as the dose Dose equivalent The absorbed dose to achieve a given level of biological damage (e.g., 50% cell killing) is often different for different kinds of radiation H = QD Equivalent dose, H, is defined as the product of the absorbed dose D and the dimensionless quantity Q, which depends on LET Dependence of Q on LET LET [MeV/cm] Q 3.5 or less 1 3.5-7.0 1-2 7.0-23 2-5 23-53 5-10 53-175 10-20 γ-rays, X-rays, electrons, 1 positrons of any LET Measurement of Exposure Exposure -
Thermo Micro Rem / Micro Sievert Tissue Equivalent Survey Meters
A D V A N C E D T E C H N O L O G Y F O R A S A F E R W O R L D Micro Rem/Sievert Tissue Equivalent Survey Meter The Micro Rem and Micro Sievert models are lightweight, portable survey meters for applications where accurate dose rate measurements of low radiation levels are required. Accurate down to background levels, the Micro Rem and Micro Sievert read absorbed dose rate directly so no conversion from mR/h is required. APPLICATIONS The tissue-equivalent scintillator used in the Micro Rem and Micro Sievert gives them a nearly flat, rem energy response. This rem response is based • Routine low/medium level gamma dose rate on the deep dose equivalent index for 1 cm (0.39”) depth, uniparallel surveys directional beam as calculated on the ICRU standard sphere. • Confirming radiation boundaries • Monitoring items for unrestricted release These instruments give tissue equivalent photon response for x-ray and • X-ray surveys, using the expanded low gamma radiation from environmental levels of 0-20 μrem/h (o-0.2 μ Sv/h) energy range option full scale up to normal survey levels of 200 mrem/h (2 mSv/h) full scale. Rugged construction and quality components make the Micro Rem and Options Micro Sievert durable, and they are easy to service. Internal components You can “customize” your instrument with practical are laid out on modular circuit boards. Span, HV and calibration pots (one options to match the requirements of your survey for each range) are clearly marked. -
Internal and External Exposure Exposure Routes 2.1
Exposure Routes Internal and External Exposure Exposure Routes 2.1 External exposure Internal exposure Body surface From outer space contamination and the sun Inhalation Suspended matters Food and drink consumption From a radiation Lungs generator Radio‐ pharmaceuticals Wound Buildings Ground Radiation coming from outside the body Radiation emitted within the body Radioactive The body is equally exposed to radiation in both cases. materials "Radiation exposure" refers to the situation where the body is in the presence of radiation. There are two types of radiation exposure, "internal exposure" and "external exposure." External exposure means to receive radiation that comes from radioactive materials existing on the ground, suspended in the air, or attached to clothes or the surface of the body (p.25 of Vol. 1, "External Exposure and Skin"). Conversely, internal exposure is caused (i) when a person has a meal and takes in radioactive materials in the food or drink (ingestion); (ii) when a person breathes in radioactive materials in the air (inhalation); (iii) when radioactive materials are absorbed through the skin (percutaneous absorption); (iv) when radioactive materials enter the body from a wound (wound contamination); and (v) when radiopharmaceuticals containing radioactive materials are administered for the purpose of medical treatment. Once radioactive materials enter the body, the body will continue to be exposed to radiation until the radioactive materials are excreted in the urine or feces (biological half-life) or as the radioactivity weakens over time (p.26 of Vol. 1, "Internal Exposure"). The difference between internal exposure and external exposure lies in whether the source that emits radiation is inside or outside the body. -
Conception and Realization of a Parallel-Plate Free-Air Ionization
Conception and realization of a parallel-plate free-air ionization chamber for the absolute dosimetry of an ultrasoft X-ray beam J.-E Groetz, Nabil Ounoughi, C Mavon, A Belafrites, M Fromm To cite this version: J.-E Groetz, Nabil Ounoughi, C Mavon, A Belafrites, M Fromm. Conception and realization of a parallel-plate free-air ionization chamber for the absolute dosimetry of an ultrasoft X-ray beam. Re- view of Scientific Instruments, American Institute of Physics, 2014, 85, pp.83304. 10.1063/1.4890817. hal-01117735 HAL Id: hal-01117735 https://hal.archives-ouvertes.fr/hal-01117735 Submitted on 17 Feb 2015 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Conception and realization of a parallel-plate free-air ionization chamber for the absolute dosimetry of an ultrasoft X-ray beam J.-E. Groetz,1, a) N. Ounoughi,1, 2 C. Mavon,1 A.Belafrites,2 and M. Fromm1 1)Laboratoire Chrono-Environnement UMR CNRS 6249, 5 Universit´ede Franche-Comt´e,16 route de Gray, 25030 Besan¸conCedex, France 2)Laboratoire de Physique des Rayonnements et Applications, Universit´ede Jijel, B.P. 98 Ouled Aissa, Jijel 18000, Alg´erie (Dated: 20 June 2014) 10 We report the design of a millimeter-sized parallel plate free-air ionization chamber (IC) aimed at determining the absolute air kerma rate of an ultra-soft X-ray beam (E = 1:5 keV). -
Radioactive Materials Transportation and Incident Response
RADIOACTIVE MATERIALS TRANSPORTATION AND INCIDENT RESPONSE U.S. Department of Energy Transportation Emergency Preparedness Program Q&A About Incident Response 04/12 QA Phone Number Radio Frequency Law Enforcement ____________________________________ RADIOACTIVE Fire ___________________________________________ MATERIALS Medical ____________________________________________ TRANSPORTATION AND INCIDENT RESPONSE State Radiological Assistance ___________________________ Local Government Official ______________________________ Local Emergency Management Agency ___________________ State Emergency Management Agency ___________________ HAZMAT Team ______________________________________ Water Pollution Control ________________________________ CHEMTEL (Toll-free US & Canada) 1-800-255-3924 _________ CHEMTREC (Toll-free US & Canada) 1-800-424-9300 _______ CHEMTREC (Outside US) 1-703-527-3887 ________________ National Response Center (Toll-free US & Canada) 1-800-424-8802 ____________ In Washington, D.C. 1-202-267-2675 _____________________ Military Shipments (DoD) Call Collect 1-703-697-0218 _______ Other: ______________________________________________ Other: ______________________________________________ QQ&A About Incident Response NOTES TABLE OF CONTENTS What is radiation?.................................................................................... 2 ______________________________________________ What is radiation exposure? .................................................................... 3 ______________________________________________