Nivaar worked solution (AI-drafted; not reviewed by a licensed engineer)
Paper format. 98-Phys-B1 Radiation Physics, National Examination December 2017 — a three-hour open-book examination in which any non-communicating calculator is permitted (the candidate must record the calculator's make and model on the first sheet). The cover page states the exam has 7 questions worth a total of 74 points, of which only 60 points' worth need be answered for full marks; every question and sub-part is nonetheless answered in full below so the paper remains a complete study resource. The cover page also invites the candidate to submit a written statement of any assumptions made where a question is open to interpretation — this licence is used below in Question 1(a)–(b) (the historic DOE report's "roentgens per hour" reading is converted to absorbed dose using the standard air-kerma factor since no calibration medium is stated) and 1(e) (the Canadian nuclear-energy-worker annual effective-dose limit, 50 mSv/yr, is used to size the inspection-crew rotation since the source states no dose constraint of its own), and in Question 6(a) (counting-statistics uncertainty is taken as Poisson, $\sigma(C)=\sqrt{C}$, on the one-minute count reported in each row, since the source gives no separate counting-time datum). Question 6 also carries a genuine internal inconsistency between the table header's definition of $g(t)$ and the definition restated in part (c) — both readings and the resolution adopted are flagged where they occur.
Reference texts. K. S. Krane, Introductory Nuclear Physics (nuclear reaction kinematics, pair production, fission energetics); F. H. Attix, Introduction to Radiological Physics and Radiation Dosimetry (exposure–dose conversion, photon interactions, non-ionizing radiation); J. R. Cember and T. E. Johnson, Introduction to Health Physics, 5th ed. (radiation weighting factors, ALARA dose planning, decay-counting statistics); J. E. Turner, Atoms, Radiation, and Radiation Protection, 3rd ed. (neutron detectors, radioactive decay/in-growth kinetics, radiation protection principles).
