Session II.3.11
Part II Quantities and Measurements
Module 3 Principles of Radiation
Detection and Measurement
Session 11 Other Detectors
3/2003 Rev 1
IAEA Post Graduate Educational Course
Radiation Protection and Safe Use of Radiation Sources
II.3.11 – slide 1 of 25
Overview
 Various kinds of radiation detectors will be
discussed and their principles of operation
explained
 Students will learn about Electrets; selfpowered detectors; thermally stimulated
exoelectron emission (TSEE); and
radiophotoluminescent detectors (RPLD)
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II.3.11 – slide 2 of 25
Content
 Electrets
 Self-powered detectors
 Thermally stimulated exoelectron
emission (TSEE)
 Radiophotoluminescent detectors
(RPLD)
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II.3.11 – slide 3 of 25
Electrets
 Semi-permanently electrically charged
material
 Usually a type of plastic insulator
 Requires a special reader and the use of
calibration factors specific to each type
 Electrets most often used for measurement
of radon, both short- and long-term, and
surface alpha detection
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II.3.11 – slide 4 of 25
Radon Electret
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E-PERM Alpha Surface Monitor
(Electret)
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Electret Voltage Reader
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E-PERM Electret Voltage Reader
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Two Sizes of Electrets
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Electret Microprocessor
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Self-Powered
Radiation Detectors
 Two examples will be given:
 Self-powered neutron detectors used in
nuclear power stations
 Self-powered Geiger counters
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II.3.11 – slide 11 of 25
Self-Powered
Neutron Detectors
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Self-Powered Geiger Counters
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Self-Powered Geiger Counters
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Test Source for
Self-Powered Geiger Counters
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Thermally Stimulated
Exoelectron Emission (TSEE)
 Refers to heating of a material after it has
been exposed to radiation
 Irradiation leaves the material in an excited
state (i.e. a state of disequilibrium)
 Heating the material stimulates electron
emission, which produces a current which
can be measured and related to the dose
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II.3.11 – slide 16 of 25
Thermally Stimulated
Exoelectron Emission (TSEE)
 A French-German cooperative project
developed a TSEE counting system for
exoelectron research
 System uses BeO thin film detectors, a
heater and a geiger counter to measure the
electrons released
 Dose range is from 10-3 cGy to above
10 cGy
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II.3.11 – slide 17 of 25
Thermally Stimulated
Exoelectron Emission (TSEE)
 Thin aluminum layers have been used for
TSEE detection of alpha and beta particles
 Method can be applied to monitoring of
alpha emitters, contamination control of
tritium, and to skin dosimetry of high LET
radiations
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II.3.11 – slide 18 of 25
Thermally Stimulated
Exoelectron Emission (TSEE)
 TSEE has been applied to personal beta
dosimetry
 Dosimeters have been developed using
TSEE from LiF
 Sensitivity of this method ranges as low as
30 Gy
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Radiophotoluminescence
(RPLD)
 Radiophotoluminescence is the property of
certain glasses (e.g. silver-activated
phosphate glass) to store the energy from
radiation until the glass is exposed to
ultraviolet light, at which time the energy is
released in the form of orange light.
 A fluorimeter is used to measure the light
output.
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II.3.11 – slide 20 of 25
Summary
 Various kinds of radiation detectors were
discussed and their principles of operation
explained
 Students learned about Electrets; selfpowered detectors; thermally stimulated
exoelectron emission (TSEE); and
radiophotoluminescent detectors (RPLD)
3/2003 Rev 1
II.3.11 – slide 21 of 25
Where to Get More Information
 Knoll, G.T., Radiation Detection and
Measurement, 3rd Edition, Wiley, New York (2000)
 Attix, F.H., Introduction to Radiological Physics
and Radiation Dosimetry, Wiley, New York (1986)
 International Atomic Energy Agency,
Determination of Absorbed Dose in Photon and
Electron Beams, 2nd Edition, Technical Reports
Series No. 277, IAEA, Vienna (1997)
3/2003 Rev 1
II.3.11 – slide 22 of 25
Where to Get More Information
 International Commission on Radiation Units
and Measurements, Quantities and Units in
Radiation Protection Dosimetry, Report No. 51,
ICRU, Bethesda (1993)
 International Commission on Radiation Units
and Measurements, Fundamental Quantities and
Units for Ionizing Radiation, Report No. 60, ICRU,
Bethesda (1998)
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Where to Get More Information
 Hine, G. J. and Brownell, G. L., (Ed. ), Radiation
Dosimetry, Academic Press (New York, 1956)
 Bevelacqua, Joseph J., Contemporary Health
Physics, John Wiley & Sons, Inc. (New York, 1995)
 International Commission on Radiological
Protection, Data for Protection Against Ionizing
Radiation from External Sources: Supplement to
ICRP Publication 15. A Report of ICRP Committee 3,
ICRP Publication 21, Pergamon Press (Oxford, 1973)
3/2003 Rev 1
II.3.11 – slide 24 of 25
Where to Get More Information
 Cember, H., Introduction to Health Physics, 3rd
Edition, McGraw-Hill, New York (2000)
 Firestone, R.B., Baglin, C.M., Frank-Chu, S.Y., Eds.,
Table of Isotopes (8th Edition, 1999 update), Wiley,
New York (1999)
 International Atomic Energy Agency, The Safe Use
of Radiation Sources, Training Course Series No. 6,
IAEA, Vienna (1995)
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II.3.11 – slide 25 of 25