Module 2: Perform Contamination Survey of Individuals Using G.M. Friskers

Module 2: Perform Contamination Survey of Individuals Using G.M. Friskers

RPT 113Instructional Resources

Module 2: Perform Contamination Survey of Individuals using G.M. Friskers

Table of Contents:

Resources Key......

Module Readings and Homework......

Primary Scenario “Perform contamination survey on individual who has set off portal monitor”

Transfer Scenario “Perform contamination survey on individual who has set off alarm on GM frisker”

Module Assessment Items

Primary Scenario “Perform contamination survey on individual who has set off portal monitor”

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 “Perform contamination survey on individual who has set off portal monitor”

Core Concept: G.M. tube detector theory and operation
Homework (end of chapter)
Readings / Calculation Items / Non-calculation Items
G., Chap. 7, 244-246, 263 - 267 / G., Chap. 7, # 11 / G., Chap. 7, # 5, 17
G., Chap. 12, # 11, 16
Core Concept: Utilization of G.M. tube-based frisker
Homework (end of chapter)
Readings / Calculation Items / Non-Calculation Items
G., Chap. 12, 504-519
DOE-SG-Mod 2.17-3 through 2.17-11 / N/A / DOE-SG-Mod2.17.01-2.17.04

Transfer Scenario “Perform contamination survey on individual who has set off alarm on GM frisker”

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 “Perform contamination survey on individual who has set off portal monitor”

1. (Inference) A mechanic is exiting from a radiological area and passes through a portal contamination monitor. The monitor senses a high amount of radiation coming from the mechanic's left shoe region and it alarms. What type of radiation detector would you use to locate the source of radiation on the mechanic and why?

A.) An ion chamber detector without a beta window so a gamma dose rate can be determined

B.) A cylindrical G.M. detector without a beta window so an accurate gamma dose rate can be determined

D.) A pancake G.M. detector with a mica window so a total count rate can be determined (Correct)

E.) A cylindrical G.M. detector without a beta window so a gamma count rate can be determined

2. (Prediction) When using a G.M. pancake detector to detect contamination on something, what impact would weak batteries have on the cpm reading

A.) The reading will be lower than actual (Correct)

B.) The reading will be higher than actual

C.) The reading would not be affected by the battery condition

D.) There would be no reading if the battery voltage is not optimum.

3. (Inference) While conducting a contamination survey of a person's clothes, you notice that the meter reads about 200 cpm above background. It doesn’t seem to matter where you survey, the reading stays the same. What likely occurred to cause the meter to read the same at all locations?

A.) The person was contaminated all over

B.) The instrument's batteries are low

C.) The detector probe is contaminated (Correct)

D.) The detector has gone into continuous discharge

4. (Inference) While surveying the outside of a person's hard hat for contamination with a pancake G.M. detector, you notice that as you move the detector probe about 1 inch away from the surface, the cpm drops off to background levels. As you move the probe closer to the surface, you see the cpm reading increase above background levels. What can you surmise about the impact of the contamination on the person's whole body dose.

A.) The contamination on the person's hard hat has no impact on the person's whole body dose because the radiation is likely alpha (Correct)

B.) The contamination on the person's hard hat increases the person's whole body dose because it is giving off beta radiation

C.) The contamination on the person's hard hat has no impact on the person's whole body dose because it is likely giving off beta radiation

D.) The contamination on the person's hard hat increases the person's whole body dose because it is likely giving off gamma radiation

5. (Inference) When considering all of the regions of the gas-filled detector curve, which region would result the largest, usable electronic signal from the detector and why?

A.) Continuous Discharge because of high voltage

B.) G.M. because of the electronic avalanche

C.) Ionization because of high current

D.) Recombination because of low voltage

Suggested Labs

Spectrum Lab #1 - Plotting a Geiger Plateau, page 12

Spectrum Lab #3 – Background, page 25
ACAD References

ACAD
1.1.8 Radiation Protection and Detection
  • Explain exposure control including the following
–Contamination
–Decontamination
3.2.3 Radiological Survey and Analysis Instruments
  • Perform and describe operational checks on survey instruments, such as battery, zero, source, response, background and calibration *

  • Identify the instruments available for performing contamination surveys such as the following
–Geiger-Mueller tubes
  • Explain the operating characteristics and use of monitoring devices including the following monitors:
–Personnel whole-body contamination
–Portal
3.3.13 Decontamination
  • Describe the procedure to be followed when an individual is contaminated, including:
–Performing a contamination survey (whole-body) by radiological protection personnel
–Recording contamination levels, location, date, and time on personnel contamination report
–Interviewing individual to identify source of contamination
  • Explain the importance of tracking and trending personnel contaminations.

  • Select the appropriate personnel decontamination techniques for various levels of contamination and the degree to which contamination is fixed.
–Removing particles with tape
–Scrubbing gently with soft brush
–Shaving contaminated hair
–Sweating and chemical decontamination
–Washing with lukewarm water and mild detergent
  • Explain why hot water, cold water and abrasive cleaners are not used for personnel decontamination.

  • Identify situations in which personnel decontamination is to be referred to other appropriate personnel.
–Contaminated wounds
–Contaminated eyes, ears, nose, or throat
–Contamination that cannot be removed using approved techniques

*ACAD is also referenced in other courses of the curriculum

Module Perform Contamination Survey of Individuals using G.M. Friskers

The Curators of the University of Missouri

Copyright © 2008-2009

A Product of DOL Grant #HG-15355-06-60

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