A.1 This Annex is normative sources.A.2 In devices that use a rack to hold the specimens and rotate them around a radiation source [shown at the centre of Figures A1 a) and b)], measure the irradiance at a position in the specimen rack that is closest to the radiation source (position A in Figure A.1) and at two positions within the specimen rack that are farthest from the radiation source (position B in Figure A.1). Measurements made with a radiometer that is placed on the rack as it rotates around the radiation source will give the most realistic indication of irradiance uniformity. The relationship between the irradiance at position B relative to the irradiance at position A shall be as follows: