RPT 113 Instructional Resources
Module 5: Perform Swipe Sample Counting Using Proportional Counters
Table of Contents:
Resources Key 2
Module Readings and Homework 2
Primary Scenario “Determine Removable Contamination Levels in a Nuclear Research Laboratory” 2
Transfer Scenario “Determine Removable Contamination Levels for Common Carrier Shipment from Power Reactor” 2
Module Assessment Items 3
Primary Scenario “Determine Removable Contamination Levels in a Nuclear Research Laboratory” 3
Suggested Labs 4
ACAD References 5
Resources Key
This refers to: / This reference:ACAD / National Academy for Nuclear Training, Uniform Curriculum Guide for Nuclear Power Plant Technician, Maintenance, and Nonlicensed Operations Personnel Associate Degree Programs, ACAD 08-006.
DOE-SG / Office of Environmental, Safety and Health: Radiological Control Technician Training Site Academic Training Study Guide Phase I, Project Number TRNG-0003
Available at: http://nsedu.rnet.missouri.edu/docshare/. File is located under the Docs/General Curriculum/DOE materials folder.
G. / Gollnick, D. (2006). Basic Radiation Protection Technology, 5th Ed. Pacific Radiation Corporation, Altadena, CA.
Spectrum / Spectrum Spectroscopy Techniques Lab Manual (Instructors and Student Versions)
Supl. Lab / Supplemental Lab Manual (instructors and Student Versions)
Module Readings and Homework
Primary Scenario “Determine Removable Contamination Levels in a Nuclear Research Laboratory”
Core Concept: Proportional Counter Theory and OperationHomework (end of chapter)
Readings / Calculation Items / Non-calculation Items
G., Chap. 7, 254-256
DOE SG 1.13-14 through 1.13-17
DOE SG 2.19-7 through 2.19-8 / G., Chap. 7, #9 / G., Chap.7, #1
Transfer Scenario “Determine Removable Contamination Levels for Common Carrier Shipment from Power Reactor”
Refer to readings and homework for primary scenario above.
Module Assessment Items
Note: If instructors wish to increase the difficulty of any item, then we suggest you use it as the basis for an in-class discussion, and / or require students to write an explanation for why a particular choice is correct.
Primary Scenario “Determine Removable Contamination Levels in a Nuclear Research Laboratory”
John is a Radiation Protection Technician at the Douglas Nuclear Power Plant. He has been assigned to perform a routine daily contamination survey of the hot chemistry lab where analyses are performed on radioactive reactor coolant samples. It has been over a year since John has personally performed this routine survey, so he is not aware of the most recent conditions. John is aware that since he performed this survey last, the radioactive content of the reactor coolant has increased due to a few pin-hole leaks in some fuel rods during operation. Historically, general area radiation levels in the lab have been below 1 mrem/hr (10 μSv/hr) and contamination levels below 1000 dpm/ 100 cm2 with the exception of a few incidents where fluid samples have been spilled. John is an experienced technician and has a high level of radiological awareness.
1. (Inference) What information will John want to collect to before he performs the contamination survey?
A.) The number of leaking fuel rods and the time since the leaks developed.
B.) The results of yesterday’s radiation and contamination survey in the lab (Correct)
C.) The half-life of the predominate isotope in the lab
D.) The time of the last analysis run in the lab
2. (Inference) Which of the following detectors will John use to perform the different parts of the contamination survey?
A.) Ionization for general area radiation, Scintillation for contamination field-check, and G.M. for swipe counting
B.) G.M. for general area radiation, Ionization for contamination field-check, and HPGe for swipe counting
C.) Gas-Flow Proportional for general area radiation, G.M. for contamination field-check, and Ionization for swipe counting
D.) Ionization for general area radiation, G.M. for contamination field-check, and Gas-Flow Proportional for swipe counting (Correct)
3. (Inference) How will loss of fill gas in a gas-flow proportional counter affect the instrument?
A.) The detector will generate more pulses and indicate higher-than-actual radiation.
B.) The detector will generate fewer pulses and indicate higher-than-actual radiation
C.) The detector will generate more pulses and indicate lower-than-actual radiation
D.) The detector will generate fewer pulses and indicate lower-than-actual radiation (Correct)
4. (Explanation) Which answer below best explains why the electrodes in Gas-Flow Proportional counters are smaller in diameter that the electrodes in Ionization chambers?
A.) To decrease electric field strength and minimize gas multiplication in the detector
B.) To increase electric field strength and maximize gas multiplication in the detector (Correct)
C.) To discriminate pulse size
D.) To prevent discrimination of pulse size
5. (Inference) How does a Gas-Flow Proportional counter differentiate between alpha radiation and beta radiation?
A.) Beta radiation produces a greater pulse because of its greater penetrating ability
B.) Alpha radiation produces a greater pulse because of its higher energy (Correct)
C.) Beta radiation produces a greater pulse because it carries a greater percentage of its decay energy than alpha radiation does.
D.) It does not differentiate between alpha and beta radiation
Suggested Labs
Supl. Lab # 15: Beta Counting with proportional counters, page 7.
ACAD References
ACAD3.2.2 Radiation Detection and Measurement Principals
· Explain the function of an ion chamber, proportional counter, alpha scintillation detectors, plastic scintillation detectors and Geiger-Mueller counter *
3.2.3 Radiological Survey and Analysis Instruments
· Convert meter indications of contamination detection equipment to contamination levels in standard units (cpm to dpm/100cm2)
· Explain the operating characteristics and use of the following radiological survey and analysis instruments:
– Proportional counters
– Smear counter
*ACAD is also referenced in other courses of the curriculum
Module Perform Swipe Sample Counting Using Proportional Counters
The Curators of the University of Missouri
Copyright © 2008-2009
A Product of DOL Grant # HG-15355-06-60
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