RPT 113Instructional Resources
Module 4: Perform Field Checks for Contamination Surveys using G.M. Friskers
Table of Contents:
Resources Key......
Module Readings and Homework......
Primary Scenario “Determine Contamination levels in Lay Down Room”......
Transfer Scenario “Determine Contamination Levels in a Nuclear Research laboratory”
Module Assessment Items
Primary Scenario “Determine Contamination levels in Lay Down Room”......
Suggested Labs......
ACAD References......
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: 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 Contamination levels in Lay Down Room”
Core Concept: Assessing removable radioactive contamination using smears or swipesHomework (end of chapter)
Readings / Calculation Items / Non-calculation Items
G., Chap. 12, # 522-523
DOE-SG-Mod. 2.05-2 – 2.05-3 / N/A / DOE-SG-Mod. 2.05.01-02
Core Concept: Field monitoring
Homework (end of chapter)
Readings / Calculation Items / Non-calculation Items
DOE-SG-Mod. 2.05-4 – 2.05-5
DOE-SG-Mod. 2.17-10-2.17-15 / N/A / DOE-SG-Mod. 2.17-03
Core Concept: G.M. frisker efficiency
Homework (end of chapter)
Readings / Calculation Items / Non-calculation Items
DOE-SG-Mod. 2.03-18-2.03-20 / G., Chap. 12, # 32
DOE-SG-Mod. 2.03.13 / DOE-SG-Mod. 2.03.12
Transfer Scenario “Determine Contamination Levels in a Nuclear Research laboratory”
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 Contamination levels in Lay Down Room”
As a Radiation Protection Technician at a nuclear power plant you have been asked to perform a loose surface contamination survey of a maintenance room where maintenance has been performed on a 6-inch valve that was removed from the reactor coolant system. The disk and valve seat inside the valve were replaced. Now that the maintenance is complete, and cleanup conducted after the maintenance, the only object in the maintenance area is the newly repaired valve awaiting reinstallation in the reactor coolant system. There is no airborne contamination in the maintenance room. No radiation or contamination survey has been taken since removing the old valve components and cleaning up the room.
1. (Inference) Which of the following is the most important thing to consider first before conducting the contamination survey?
A.) The anticipated contamination levels in the area
B.) The anticipated radiation levels in the area (Correct)
C.) The protective clothing needed to complete the survey
D.) The type of instrument needed to complete the survey
2. (Explanation) Which reason best explains your answer to Question 1?
A.) Since you are conducting a contamination survey and not a radiation survey, knowing the anticipated contamination levels is most important to ensure you do not get contaminated.
B.) Radiation can pass through protective clothing, while the contamination cannot, therefore it is a more important consideration. (Correct)
C.) Since you could get contaminated while taking the survey, the protective clothing is most important to prevent personal contamination. Personal contamination is worse than radiation dose.
D.) Determining the type of instrument needed is most important to ensure you get accurate contamination measurements.
3. (Prediction) What should your actions be if the background radiation is 400 cpm when counting smears with a GM pancake detector and count rate meter?
A.) Use an ion chamber detector
B.) Subtract 400 CPM from total cpm to get cpm of the smear
C.) Go to an area with lower than 300 cpm background radiation (Correct)
D.) Hold the detector probe closer to the smear to get a more accurate reading
4. (Explanation) If you are trying to detect alpha, beta, and gamma emitting contamination on a smear using a typical G.M. pancake probe why would you hold the frisker probe ¼ inch from the smear?
A.) Because you are trying to detect alpha, beta, and gamma radiation. (Correct)
B.) You do not – you hold it 1/2 in from the smear.
C.) To ensure all of the gamma radiation can penetrate the detector window.
D.) To ensure all of the beta radiation can penetrate the detector window.
5.) (Explanation) Why would a technician use an ion chamber to quantify loose surface contamination?
A.) Because a count rate meter with a GM detector registers less than 300 cpm.
B.) Because an ion chamber is superior at detecting alpha contamination.
C.) Because it is desirable to measure contamination in an area with background greater than 300 cpm on a count rate meter with a GM detector.
D.) Because the cpm reading exceeds the upper range of the count rate meter using a GM-detector (Correct)
Suggested Labs
Contamination surveys with Teletrix SP900 simulated contamination detector (chemically based). No laboratory procedure given- at instructor’s discretion
ACAD References
3.2.3 Radiological Survey and Analysis Instruments
- Demonstrate proper techniques for surveying an item for contamination (loose and fixed) using a hand-held frisker
- Explain the operating characteristics and use of the following radiological survey and analysis instruments:
–Frisker
3.3.12 Radiological Incident Evaluation and Control
- Describe how to estimate beta and gamma dose rates from the following:
Module Perform Field Checks for Contamination Surveys using G.M. Friskers
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