|Estimation of cancer risk for small doses:|
The potential biological effects for weak doses of radiation are both too small and too dominated by the laws of chance to allow for any accurate measurements. This lack of data has prompted the ICRP to tender the hypothesis that the effect varies proportionally with the dose. The relationship thus becomes a straight line passing through the origin and the closest possible to the actual data points available. The graphs can be used to deduce a likelihood of 5% rate of developing a fatal cancer per sievert. A logarithmic scale is necessary to represent doses and effects over several orders of magnitude.