1 / 18

2008-2009 Progress on Direct Alpha Analysis for Forensic Samples (DAAFS) CRTI Project 07-0113TD

2008-2009 Progress on Direct Alpha Analysis for Forensic Samples (DAAFS) CRTI Project 07-0113TD CRTI Symposium 2009 Ian Hoffman, Health Canada. Partners. Health Canada STUK (Finland’s Radiation and Nuclear Safety Authority) International Safety Research Canadian Nuclear Safety Commission

kaycee
Download Presentation

2008-2009 Progress on Direct Alpha Analysis for Forensic Samples (DAAFS) CRTI Project 07-0113TD

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. 2008-2009 Progress on Direct Alpha Analysis for Forensic Samples (DAAFS) CRTI Project 07-0113TD CRTI Symposium 2009 Ian Hoffman, Health Canada

  2. Partners • Health Canada • STUK (Finland’s Radiation and Nuclear Safety Authority) • International Safety Research • Canadian Nuclear Safety Commission • Defence Research and Development Canada • Royal Canadian Mounted Police • Atomic Weapons Establishment (UK)

  3. Contents Objectives of the Project Relevance to CRTI Priorities Brief Backgrounder on Alpha Radiation Progress and Results Impact on Canada’s Ability to Respond Conclusion

  4. Objectives • Goal: To create a field deployable alpha spectrometry system that will perform direct measurement of forensic samples for difficult to detect radioactive isotopes. • How: Using well characterized sampling techniques and advanced spectral de-convolution codes, it is possible to “unwrap” the isotopic components of a complex alpha spectra • Result: First responders will collect samples allowing experts to identify and quantify the presence of alpha emitters to assess the risk to the response team and the public through a non-destructive field test. Results are available in hours rather than the current standard of days.

  5. Relevance to CRTI Investment Areas • CNSIC 1: Portable sampling equipment will significantly reduce the equipment encumbrance normally present for (HAZMAT) and forensic teams. • CNSIC 2: Security of the public enhanced through timely, accurate identification of crime scene boundaries. • CNSIC 5: The security and preservation of evidence will be greatly improved by the non-destructive nature of the system. Evidence is preserved for further analysis and prosecution.

  6. Objectives • Important Milestones in the DAAFS project (excerpted): • ADAM and AASI complete/Software Integration – Completed • Laboratory Trials - Ongoing • Basic Reachback Capability – Aug. 2009 • ConOps Complete – Sept. 2009 • Field Test at Exercise Gold or alternative – November 2009 • Final Reachback Capability– Aug. 2010 • Final Sampling Kit – Dec. 2010 • Project End – Mar. 2011

  7. A Brief Backgrounder on Alpha Radiation • Gamma radiation is highly penetrative! Lead shielding necessary to attenuate/protect. Alpha radiation is very different in important ways. • Alpha Radiation is much higher in energy with larger, more damaging particles. • Alpha particles have a range of only a few cm in air. This is a both a blessing and a curse. • Difficult to detect due to short range. • Typically not a threat as long as it is external to body! Skin is an effective barrier. • Alpha particles internally are tremendously dangerous • Need to be careful of ingestion/inhalation. Litvineko had 10 μg of Po-210 in his body. Median lethal amount is only 50 ng. • From health physics, gamma radiation has a QF=1, while alpha = 20 (1950s numbers). Modern estimates give a QF up to 1000. • A few counts can mean a massive dose, if not managed properly.

  8. Progress and Results What’s been done? • Bulk of hardware acquired for project • Initial project meeting with STUK in December 2008 • Prototype software/system installed at HC • 3 HC users trained in software operation (simulation and measurement software) • Framework/outline of ConOps established • Sample acquisition training course delivered by STUK in March 2009 • Delivery of air filter sampling nozzle and kit • Preliminary trial results sampling methods tested by STUK shared • Samples have been collected, analysed on our equipment April 2009

  9. Sampling methods Sampling methods tested: IAEA cotton swipe Swipe with Fluoropore membrane filter IAEA impactor Intake nozzle Blowing head Other sampling methods (to be tested): Sticky tapes Empore } Methods utilizing air stream

  10. Sampling Technique - Conventional • Simulation of a cotton cloth swipe of dust. • No particular sampling methodology used. • Difficult to distinguish individual isotopes • Energy of peaks shifted • Long counting times do not help • Radiochemistry necessary for analysis

  11. Glass-fibre filter Membrane filter 214Po 214Po 218Po 212Po 212Bi 218Po 212Po 212Bi Progress and Results Sampling Techniques – Simulated Spectra

  12. 210Po is present on the surfaces, not in the air! Is it possible to detect this? Demonstration of AASI – Po-210

  13. Yes it is ! Less than 1 mBq/cm2!

  14. Actual Spectra - ADAM • Alpha spectrum obtained in a 24 hour measurement of a dust sample containing Po-210

  15. ADAM Deconvolution of Natural Uranium • Alpha spectrum obtained in a 24-hour measurement of ground uranium ore

  16. Impact on Response Capability • The DAAFS system allows: • Non destructive alpha spectrometry on samples – multiple analysis possible on same sample • Relatively rapid assessment of samples with no need for laboratory isotopic separation • High throughput – establish crime scene boundaries rapidly • Access to offsite experts for confirmatory analysis/expertise through reachback • Alarming capable

  17. Potential Applications and Spin-Offs • During FY2 and FY3 and beyond, the concepts/technology used in DAAFS will be investigated for applicability to: • Gross alpha monitoring for groundwater regulatory measurement requirements • Non-ideal samples – liquids, snow, non-fluoropore swipes • Urine analysis - U234/238 ratios for occupational/environmental exposure • Decontamination of sites • COG – CANDU Owners’ Group • Nuclear safeguards/security with CNSC/IAEA

  18. Conclusion • Direct alpha spectroscopy is proving to be a useful and feasible technique with multiple applications • The combination of simulation and actual measurement is powerful for performing research and validation • Sampling techniques are being developed – success demonstrated, however more methods will be tested. • AASI alpha simulation code freely available (with registration) at: • http://www.stuk.fi/tutkimus/programs/aasi/en_GB/aasi/

More Related