title: An estimation of Canadian population exposure to cosmic rays.
abstract: The worldwide average exposure to cosmic rays contributes to about 16% of the annual effective dose from natural radiation sources. At ground level, doses from cosmic ray exposure depend strongly on altitude, and weakly on geographical location and solar activity. With the analytical model PARMA developed by the Japan Atomic Energy Agency, annual effective doses due to cosmic ray exposure at ground level were calculated for more than 1,500 communities across Canada which cover more than 85% of the Canadian population. The annual effective doses from cosmic ray exposure in the year 2000 during solar maximum ranged from 0.27 to 0.72 mSv with the population-weighted national average of 0.30 mSv. For the year 2006 during solar minimum, the doses varied between 0.30 and 0.84 mSv, and the population-weighted national average was 0.33 mSv. Averaged over solar activity, the Canadian population-weighted average annual effective dose due to cosmic ray exposure at ground level is estimated to be 0.31 mSv.
authors.affiliation: Radiation Protection Bureau Health Canada, Ottawa, Canada. jing_chen@hc-sc.gc.ca
authors.forename: Jing
authors.initials: J
authors.lastname: Chen
authors.forename: Rachel
authors.initials: R
authors.lastname: Timmins
authors.forename: Kyle
authors.initials: K
authors.lastname: Verdecchia
authors.forename: Tatsuhiko
authors.initials: T
authors.lastname: Sato
mesh_terms: D002170:Canada; D003359:Cosmic Radiation; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D011829:Radiation Dosage