Natural Radiation Source Fabricated from Commercially Available Instant Coffee

Abstract

Commercially available instant coffee, Nescafe Excella, contained the radionuclide ⁴⁰K. From the instant coffee, sixteen coffee-block radiation sources were successfully fabricated with sufficiently low production dependences. The coffee-block radiation sources were examined their suitability for a radiation protection course. Although a part of radiation counts(cpm) obtained with 1minute measurement were largely deviated, those determined by 5 minute measurements and five times of 1 minute measurement were less deviated, enabling better comprehension of the three cardinal principles of radiation protection.