OMPI Seminar: Richard Wassenaar and Alexandra Bourgouin

Printer-friendly version
Thursday, March 21, 2019

Time: 3:30 - 5:00 pm, Refreshments start at 3:15 pm.

Location: Health Canada, Radiation Protection Building, 775 Brookfield Road, Room 205B


1) Determination of W(air) in high-energy electron beams

by Alexandra Bourgouin, PhD Candidate, Carleton University, Department of Physics

Supervisor: Malcolm McEwan

Abstract: The mean energy required to create ion pair in air, W(air), is considered to be energy independent above 10 keV. However, an extreme interpretation of the available data would allow a variation of up to 2% in the clinical energy range. To investigate this, a graphite ionization chamber and calorimeter with the same geometry and sensitive volume were irradiated with high energy electron beams to yield a value for W(air). Although the experiment yielded a value consistent with the ICRU #90 value, it highlighted the problems of using graphite detectors, particularly related to density variations. To obtain additional experimental data in high-energy electron beams to determine W(air), a pure aluminium detector has been designed, built and is now being commissioned.


2) Development of Occupational Dosimetry Metrics for a Source Manufacturer

by Richard Wassenaar, PhD, Nordion (Canada)

Abstract: Nordion is a manufacturer and world-wide distributor of radioisotope sources. Open sources of radioisotopes are received from various reactors. The radioisotopes are processed and manufactured into sources destined for health care facilities and industrial irradiators. Given the high-activity, high-radiation risk nature of the work, Nordion has implemented a robust occupational radiation dosimetry program for its workers. In this talk, I will present some of the work Nordion is doing to further develop metrics for dosimetry analysis to improve evaluation of personnel doses. I will discuss the analysis of data undertaken as a result of the recent revision regarding the lens of the eye doses and present an interesting case study that was found during the analysis. In addition, I will present my work relating to automated statistical analysis of personnel’s dosimetry measurements.