HUMAN-CENTRIC NON-INVASIVE PHYSIOLOGICAL SENSING SYSTEM FOR EARLY DETECTION OF WORKERS? HEAT STRESS IN THE FIELD

HUMAN-CENTRIC NON-INVASIVE PHYSIOLOGICAL SENSING SYSTEM FOR EARLY DETECTION OF WORKERS' HEAT STRESS IN THE FIELD PROJECT SUMMARY Heat stress can abruptly raise the core body temperature above a safe threshold, shut down the temperature- regulating system, and result in severe organ failure and even death. Long-term consequences of heat stress can increase the chances of developing cardiovascular, respiratory diseases, and chronic kidney diseases. Due to intensive physical labor and the use of protective clothing, many workers in heat-vulnerable industries, such as construction, firefighting, and farm work, among other populations such as soldiers and athletes, have a limited set of fundamental precautions for preventing traumatic or catastrophic heat stress. Also, the current heat-stress regulations are based on overly general environmental or working conditions, not specific to individuals. These methods do not account for workers' physical and physiological characteristics, and they may reflect dissimilar responses to heat exposure even under similar conditions or similar responses when workers are experiencing different conditions. As a result, any detailed protocol for early heat stress prediction is almost entirely missing, and heat-stress interventions generally occur well after exposure becomes critical. The overarching goal of this R21 project is to develop and evaluate a worker-centered heat stress monitoring framework based on physiological and environmental signals. This system predicts workers' heat-stress exposure at job sites by continuously interpreting biosignals and environmental signals through the use of context-sensitive, data-driven, machine-learning models in real-time. This project intends to prevent deaths and catastrophic injuries such as brain damage in labor-intensive industries that need to improve heat-trauma procedures but lack sensitive means. As such, the proposed framework is a critical step towards reaching key NIOSH strategic goal 6: "improve workplace safety to reduce traumatic injuries" for NORA sector 21, mining, with intermediate goal 6.9, "excessive heat exposure," and strategic goal 7: "promote safe and healthy work design and well-being" for NORA sector 23, construction, with intermediate goal 7.1, "non- standard work arrangements." The proposed research will pursue NIOSH's strategic goals following our specific aims. The first aim is to design and fabricate a non-invasive wireless physiological sensing system for continuous elicitation of physiological responses (photoplethysmography [PPG], electrodermal activity [EDA], electrocardiogram [ECG], skin temperature [ST], and core temperature [Tc]) that can predominantly assess workers' heat-stress exposure. The second aim is to develop a physiologically based data-driven framework for early prediction of workers' heat stress exposure. The third aim is to evaluate the performance of the developed wireless sensing system and predictive data-driven framework in both a controlled and naturalistic environment. The proposed system has a high potential to prevent workers from severe heat-related injuries by triggering safety feedbacks to workers timely. The proposed system will also allow new workers to safely start their job, build up a tolerance for hot conditions, and acclimatize to the workplace.