'Summertime Evaluation and Intercomparison of Wet Bulb Globe Temperature Observing Systems on Texas A&M University's Campus'

Wet Bulb Globe Temperature (WBGT) provides holistic evaluation of heat stress by taking into account temperature, humidity, wind speed, and the intensity of solar radiation an individual is experiencing outside. While the metric has been known to the scientific community, the general public has recently exposed more readily to WBGT measurements, as, for example, many sports governing bodies have implemented heat safety measures aligned to WBGT values. With the growing need for accurate WBGT measurements, several instruments and phone application estimates have been developed to provide guidance on WBGT. However, little to no evaluation of the accuracy of these sensing platforms has been undertaken, nor do people have a great understanding of what WBGT values actually mean.

During the first two weeks in August of 2024, Texas A&M University evaluated a suite of WBGT sensors on Texas A&M’s College Station, TX campus. A control WBGT station, which served as the baseline comparison point, designed to meet the International Organization for Standardization (ISO) standards, was provided by Perry Weather Inc. WBGT measurements from the control unit were compared to two handled meters (Kestrel 5400 WBGT Heat Stress Tracker and a General Tools 8758 heat stress tracker) mounted at the same elevation as the control unit. Additionally, a Perry Weather WBGT weather station was mounted at 10-meters in height on the roof of a nearby building. The higher elevation sensor was included in the study to evaluate the differences between field level measurements and elevated measurements that might occur at a sports stadium. Lastly, Zelus, a phone application that provides estimated WBGT for a given location, but does not have a ground based sensing station on location, was also evaluated. Measurements were taken every 30-minutes on all observing platforms from 9:30am to 8:00pm local time from August 1 - August 14, 2024.

The results of the control WBGT temperature measurements will be presented in reference to the heat stress activity modification recommendation levels for the region. Additionally, the differences in WBGT measurements, variance, response time, and any differences in recommended activity modifications across the different sensors and the phone application will be presented.