Roentgen (unit) this derivative quantity the roentgen equivalent physical (rep) to distinguish it from the ICR roentgen. The introduction of the roentgen measurement unit, which relied upon measuring the ionisation of air, replaced earlier less accurate practices that relied on timed exposure, film exposure, or fluorescence. This led the way to setting exposure limits,and the National Council on Radiation Protection and Measurements of the United States established the first formal dose limit in 1931 as 0.1 roentgen per day. The International X-ray and Radium Protection Committee, now known as the International Commission on Radiological Protection (ICRP) soon followed with a limit of
Gordon Wallace (professor) been focused on exploring the development and use of such materials in biomolecular technologies – he has led a number of initiatives in developing the field of organic bionics. He has developed collaborative research relationships with the inventor of the Cochlear Bionic Ear, Professor Graeme Clark as well as Professor Stephen O'Leary, Professor Peter Choong, and Professor Mark Cook which have led to significant developments in the field of new materials for medical bionics. He has now established a significant national clinic network with others including Professor Chris Baker, Professor Michael Coote, Professor Toby Coates, Professor Gerard Sutton, Professor Stuart