A normalized contextual performance metric quantifies the susceptibility of fatigue-related risk in a fatigue environment with activities conducted within a fatigue level range of interest. Fatigue incidents are quantified by one of a plurality of values associated with fatigue-incident measurement. Activities are quantified by one of a plurality of values associated with activity measurement. A normalized contextual performance metric is determined by identifying a fatigue level range of interest, summing all values of incidents occurring at the fatigue level range of interest, summing all values for relevant activities occurring at the fatigue level range of interest, and then dividing the first sum by the second. The normalized contextual performance metric thereby allows operational managers to assess risk of fatigue incidents by monitoring activities and fatigue levels within the fatigue environment.