Angol Bridget, Sousan Sinan, Balanay Jo Anne G
Environmental Health Sciences Program, Department of Health Education and Promotion, East Carolina University, Greenville, North Carolina.
Department of Public Health, Brody School of Medicine, East Carolina University, Greenville, North Carolina.
J Occup Environ Hyg. 2025 Apr;22(4):274-287. doi: 10.1080/15459624.2024.2444415. Epub 2025 Jan 8.
The wet bulb globe temperature (WBGT) index is the preferred environmental heat metric for occupational heat-related illness prevention but may not always be readily accessible in the workplace. Thus, there is a need for well-designed WBGT-based tools that are reliable, accessible, and inexpensive. A novel WBGT app prototype was developed to calculate the current and forecasted outdoor WBGT. The purpose of this study was to assess the reliability of the WBGT app prototype in providing accurate heat stress risk information for outdoor workplace settings in eastern North Carolina by comparing the WBGT indices and risk levels from the app (WBGT) with those derived from a heat stress monitor (WBGT). Outdoor WBGT measurements were data logged at a university campus site using a heat stress monitor from March to August 2023 for 81 days and were assigned to risk levels by workload based on the ACGIH Threshold Limit Values. Hourly WBGT values and their corresponding risk levels were obtained using the app prototype. Data analysis was conducted using a t-test, Pearson correlation test, and cross-tabulation. Results showed that the hourly mean WBGT was significantly higher ( < 0.01) than the WBGT, but there was no significant difference between the overall average of the daily mean ( = 0.15) and daily maximum ( = 0.69) WBGT and WBGT. There was a strong, positive correlation between the hourly mean ( = 0.94, < 0.01), daily mean ( = 0.97, < 0.01), and daily maximum ( = 0.94, < 0.01) WBGT and WBGT. The app correctly identified 73-88% of minimal-risk conditions, depending on workload type, and was most reliable in correctly identifying extreme-risk conditions at 97%, 95%, and 93% for light, moderate, and heavy workloads, respectively. This demonstrates the app's capability of being protective of the workers, particularly in more severe heat stress risk conditions. Recommendations to improve the app's accuracy involved using accurate solar irradiance data and applying linear calibration. The WBGT app prototype shows good potential as an alternative risk assessment tool for heat stress risk among outdoor workers.
湿球黑球温度（WBGT）指数是预防职业性热相关疾病的首选环境热指标，但在工作场所可能并非总是易于获取。因此，需要设计良好、可靠、易于使用且价格低廉的基于WBGT的工具。开发了一种新型的WBGT应用程序原型来计算当前和预测的室外WBGT。本研究的目的是通过比较应用程序（WBGT）得出的WBGT指数和风险水平与热应激监测仪（WBGT）得出的指数和风险水平，评估WBGT应用程序原型在为北卡罗来纳州东部室外工作场所提供准确的热应激风险信息方面的可靠性。2023年3月至8月，在大学校园站点使用热应激监测仪对室外WBGT测量数据进行记录，共81天，并根据美国政府工业卫生学家会议（ACGIH）阈限值按工作量将其划分为风险等级。使用应用程序原型获取每小时的WBGT值及其相应的风险等级。使用t检验、Pearson相关检验和交叉表进行数据分析。结果表明，每小时平均WBGT显著高于（<0.01）WBGT，但日平均（=0.15）和日最高（=0.69）WBGT与WBGT的总体平均值之间无显著差异。每小时平均（=0.94，<0.01）、日平均（=0.97，<0.01）和日最高（=0.94，<0.01）WBGT与WBGT之间存在强烈的正相关。根据工作量类型，该应用程序正确识别了73 - 88%的最低风险状况，在正确识别极端风险状况方面最为可靠，对于轻、中、重工作量分别为97%、95%和93%。这表明该应用程序有保护工人的能力，特别是在更严重的热应激风险条件下。提高应用程序准确性的建议包括使用准确的太阳辐照度数据和应用线性校准。WBGT应用程序原型作为室外工作者热应激风险的替代风险评估工具具有良好的潜力。
