Number of accidents X hours worked divided by 100.000.

Bob, you might be right. However here is another one... Number of injuries divided by the number of employees X 100.000. That is taken direct from the MS course (which you made me open and look at at nearly 9pm!) Basically agrees with my first post ;-)

There is no official method set down in law, so how you choose to present your statistics and which method of calculation you use, is up to you. However, the publication 'Successful health and safety management' by the HSE contains guidance on incident and frequency rates: Comparing reportable injury information is just one way of assessing a firm's safety performance. In many firms, particularly those with fewer than 100 employees, reportable injuries represent only a small proportion of the total number of injuries to employees. Records of more minor, non-reportable injuries, and of 'near misses', may also be converted into incidence rates and used to monitor trends over time or between different parts of the operation. Analysis of the data to identify the main causes of injury, for example, can help to identify risks that need to be controlled and prevent further accidents. Calculation of injury incidence rates HSE's formula for calculating an annual injury incidence rate is: Number of reportable injuries in financial year ------------------------------------------------------------------- x 100 000 Average number employed during year This gives the rate per 100 000 employees. The formula makes no allowances for variations in part-time employment or overtime. It is an annual calculation and the figures need to be adjusted pro-rata if they cover a shorter period. Such shorter-term rates should be compared only with rates for exactly similar periods - not the national annual rates. Calculation of injury frequency rates While HSE calculates injury INCIDENCE RATES per 100 000 employees, some parts of industry prefer to calculate injury FREQUENCY RATES, usually per million hours worked. This method, by counting hours worked rather than the number of employees, avoids distortions which may be caused in the incidence rate calculations by part- and full-time employees and by overtime working. Frequency rates can be calculated for any time period. The calculation is: Number of injuries in the period ------------------------------------------------------ x 1 000 000 Total hours worked during the period Reference: HSG65 Successful health and safety management This can be downloaded online at the following web address: http://www.hse.gov.uk/pubns/priced/hsg65.pdf