• To access the fatigue risk calculator please visit the HSE website via the link provided.
  • The research report outlining the work carried out to revise and update the HSE Fatigue Index (FI) is available below.
  • The user guide which outlines how to use the FRC can also be found below.

The Fatigue and Risk Index (FRI) was designed primarily for comparing different shift schedules but can also be used to identify any particular shift, within a given schedule, which may be of concern.

Whilst the FRI is a useful tool, which can be used to help assess the risks of fatigue and injury, it should not be relied upon as the sole or primary means of assessing these risks.

Shift work planners should always start by considering the guidelines in Managing shift work: Health and Safety Guidance (HSG 256), which includes background information on the health and safety risks associated with shift work and fatigue, UK legal duties and practical guidance on how to reduce the risks. FRI outputs should also be considered in conjunction with feedback from staff on how tiring they find their work patterns.

When interpreting scores it is important that the scores for each shift are considered rather than the average scores over a schedule.

It is important to note that the FRI is based on group data and does not, take into account factors such as individual differences (eg age), specific work-related issues (eg exposure to chemical hazards) or social factors (eg lifestyle, domestic responsibilities), although it should be recognised that that these may affect a worker’s tolerance to shift work.