Early detection of radioactive fall-out by gamma-spectrometry

Helle Karina Aage, Uffe C C Korsbech, K. Bargholz

Research output: Contribution to journalJournal articleResearchpeer-review


Radioactive fallout should be detected as early as possible. A new and efficient method for detection of low-level irradiation from manmade radioactivity is developed. Radiation abnormalities are detectable down to air kerma rate, of 0.5 to 1.0 nGy h(-1) for Cs-137 and even lower for I-131 For multi-gamma energy radioactivity the detection level is 2.6-3.5 nGy h(-1). A standard NaI detector and a 512-channel analyser are used together with noise adjusted singular value decomposition (NASVD). Statistical noise is removed and the measured spectra are reproduced using spectral components produced by NASVD. Stripping is not used and false alarms due to washout of atmospheric radon progeny are almost eliminated. Detection levels and the criteria for setting warning and alarm levels are discussed. The method may also be useful in other situations, for example where low-level signals from radioactive sources need to be detected.
Original languageEnglish
JournalRadiation Protection Dosimetry
Issue number2
Pages (from-to)155-164
Publication statusPublished - 2003

Fingerprint Dive into the research topics of 'Early detection of radioactive fall-out by gamma-spectrometry'. Together they form a unique fingerprint.

Cite this