Fatigue assessment of construction equipment operators using a sweat lactate biosensor

This study investigated the accuracy and usefulness of a sweat-based biosensor for measuring the fatigue levels of construction equipment operators. Specifically, the paper first elaborated on the suitability of selecting sweat lactate as a biomarker for measuring combined fatigue (i.e., a combination of physical and mental fatigue) that construction equipment operators often experience. Then, the mechanism of a sweat-based sensor was explained. An experiment was then presented in which the sweat lactate levels of five subjects engaged in simulated equipment operating tasks were measured. The reliability of the sweat-based lactate sensor was also evaluated by conducting a between-day test-retest experiment. The lactate measurements of the sweat sensor were compared to measurements of blood lactate to assess the accuracy of the sweat sensor. The Fatigue Assessment Scale, a subjective fatigue method, validated sweat lactate as a fatigue assessment biomarker. Analytical results indicate that the lactate measurements from the sweat-based sensor do reflect the fatigue level of equipment operators, and the device has good reliability for measuring sweat lactate concentration.