Fatigue is a recognized contributor to increased accidents, injuries, and a variety of health conditions. In 2007 the International Association of Fire Chiefs published a report on the impact of fatigue. The report recommended that fire departments develop management plans to mitigate these risks. Recent research indicates that, over a decade later, fatigue is still having a significant impact on firefighters and EMS workers working both 24- and 48- hour shifts. In 2020-2021, 254 full-time, professional firefighters were monitored for a twoweek period. Cognitive performance tests indicated approximately one quarter of the participants were so cognitively fatigued, while on duty, that their performance was impaired to the same extent as a person who is alcohol impaired. Additionally, these firefighters reported feeling more alert despite continually declining cognitive performance. Identifying and controlling fatigue within the workplace can have a significant impact on the health and well-being of firefighters.