Health and Safety
Executive / Commission
Research reports
This report describes the work carried out to revise and update the HSE Fatigue Index (FI). Extensive changes have been made to the previous version, incorporating recent information relating to a variety of issues including cumulative fatigue, time of day, shift length, the effect of breaks and the recovery from a sequence of shifts. In addition, a review has been carried out of trends in risk related to shift work, and this has enabled the final version to incorporate two separate indices, one related to fatigue (the Fatigue Index) and the other to risk (the Risk Index). While the two indices are similar in many respects they diverge in others. The main differences are due to the different trends with respect to time of day in fatigue and risk. The index has been implemented in the form of a spreadsheet, the design of which has incorporated feedback from users of the previous index.
The Research Report Series are produced in Adobe Acrobat. The use of the latest version of the software is recommended which is available at the Adobe website via the link on this page.
Assistance in the use of Adobe Acrobat PDF files is available on our FAQs page.