Comparative Performance Analysis of Mobile Application and Instrumented Wet Bulb Globe Temperature Monitoring: A Field-Based Accuracy Assessment

Abstract

The increasing danger of environmental heat stress on outdoor workers, athletics, and vulnerable populations globally is due to the rising intensity and frequency of extreme temperatures of thermal events as climate change worsens. Wet Bulb Globe Temperature (WBGT) index is the accepted gold standard of measuring the exposure to heat stress, but outdated equipment is frequently too expensive and logistically difficult to deploy on a large scale. Mobile applications based on estimating WBGT using meteorological inputs and algorithmic models are also available as the accessible alternatives, yet their measurement accuracy in various field conditions is still not fully defined. In this research, a systematic field comparison was done between calibrated WBGT reference equipment and the American industrial hygiene association (AIHA) Heat Stress App 2.0 on 52 simultaneous measurements at 4 weeks in an outdoor occupational environment. The WBGT measurements were between 19.8°C and 39.4°C, whereas AIHA app was between 16°C and 32°C. The average systematic bias was 3.86°C (WBGT > AIHA), which had a standard deviation of 4.54°C and 95.