Toward a “Risk Index” to Assess Work Schedules

Abstract

This article describes our preliminary attempt to develop a Risk Index to estimate the risk of human error on different work schedules based on trends in the relative risk of accidents and injuries, rather than on hypothetical intervening variables such as alertness, fatigue, or performance on interpolated tasks. We briefly review trends in risk from the published epidemiological studies that have ensured that the a priori risk was constant. A simple Risk Index based on an additive model is developed on the basis of these trends, and we illustrate how it may be used to assess work schedules. Finally, we compare the results from this Risk Index with those from the UK HSE's Fatigue Index and point out the discrepancies that emerge. We conclude that our risk-based modeling approach may assist in developing safer work schedules and also increase our understanding of this complex, multifaceted area.

• Work schedules
• Worker safety
• Occupational injuries
• Work-place accidents
• Mathematical models

Notes

^aThe term “day shift” is usually used in 12 h shift systems for the shift that starts in the morning. For the sake of simplicity it is used from hereon to refer to both day and morning shifts.