non-irradiated sham-irradiated Jack Miller The class should be used in cases where it is clear that the control sample was treated in precisely the same way as the experimental samples or sham irradiation is specified. It is therefore a more restricted quality definition than "non-irradiated". It is likely to be used more often with external radiation exposure or exposure to a beam, and with a biological rather than abiotic sample. sham A quality of a biotic or abiotic sample or individual which is part of an experiment that tests the effects of radiation on organisms or materials by isolating variables as dictated by the scientific method in order to make a conclusion about the effect of such variables. In sham irradiation the precise treatment of the sample must be identical to that of the experimental samples and should be made explicit in the description of the method.