Radiation Protection Dosimetry 28:11-15 (1989)
© 1989 Oxford University Press
Issues Raised in the Limitation, Control and Measurement of Radiation Risks
Over the past few years a consistent set of quantities for ionising radiation measurements in radiological protection have been defined. The efforts being made by those concerned with radiation dosimetry to ensure the universal adoption and use of these quantities are now threatened by further developments in risk concepts. The most serious threats arise from changed perceptions about the quality factors appropriate for different radiations due to improved biological information about relative biological effectiveness, and the increased importance to be given to the cancer risk estimates derived from the Hiroshima and Nagasaki survivors following the revised dose estimates. A change in the basis of quality factor specification will require careful consideration if it is not to produce further problems in obtaining agreement on the conceptual basis for radiological protection metrology. The change is primarily for adoption in the calculation of the risk quantity, effective dose equivalent. Some of the possible options for taking account of the change in regard to the measurement quantities are: 1. Apply the changed quality factors directly in the calculation of ambient dose equivalent, directional dose equivalent, etc. 2. Retain the existing energy dependencies of the measurement quantities and apply a constant factor at all energies. 3. Apply different factors over restricted energy ranges to the measurement quantities. 4. Specify envelope functions to represent fluence or air kerma conversion factors and use these factors for the design calibration, etc. of radiation detectors for radiological protection. Of these options the second is the simplest and most economic.