Posted By John Beadle There are no standard or formal requirements in the UK for statistical formulae used for the analysis of accident data. The most often encountered are: Frequency Rate Number of injuries x 100,000 / Total number of hours worked Incidence Rate (helpful where the number of hours is either low or not available); Number of injuries x 1000 / Average number employed during the period Confusingly, the incidence rate most commonly used by the Government is: Number of fatal or major injuries x 100,000 / Number at risk in the particular industry sector The above information is taken from Principles of H&S at Work published by IOSH Regards John