Department of Health, Safety and Environment, Energy Queensland, Brisbane, Queensland, Australia.
Thermal Hyperformance, Hervey Bay, Queensland, Australia.
J Occup Environ Hyg. 2020 Nov-Dec;17(11-12):515-522. doi: 10.1080/15459624.2020.1834112. Epub 2020 Nov 16.
This study assessed self-reported heat strain symptoms in workers of a state wide electrical utility distributor to determine risk differences between age groups, geographical work regions and work units. Out of a total 3,250 workers, 918 (∼28%) outdoor staff completed an online survey, which assessed the frequency of self-reported heat strain symptoms in the work and post-work settings, factors contributing to symptoms and symptom management. Heat strain symptoms were grouped into chronic low-grade cases and isolated high-grade cases based on the severity and frequency of symptoms. The risk (likelihood) of an employee being classified as either a chronic low-grade or isolated high-grade case was calculated and compared to the mean risk of all categories to determine risk difference, expressed as -1.00 to 1.00. For chronic low-grade cases, the 41-50 years age group had significantly increased risk (+0.08, p < 0.05) while the over 60 years age group had significantly decreased risk (-0.14, p < 0.05). Two of the three regions (p < 0.01) and three of the nine work units also demonstrated risk differences (p < 0.01) for chronic low-grade cases. Work units were the sole grouping to demonstrate risk difference for isolated high-risk cases. Work units with greater exposure to heat and higher requirement for protective clothing, such as Underground (+0.19, p < 0.05), Overhead - Predominantly Live Line (+0.18, p < 0.01), and Overhead - Distribution and Transmission (+0.11, p < 0.05) were at greater risk of reporting heat stress symptoms. This study demonstrates that the pattern of self-reported chronic low-grade heat strain cases differs to isolated high-grade cases within the electrical utility industry. Age, geographical location, and work unit independently alter the risk of chronic low-grade heat strain, while the risk of isolated high-grade heat strain was only related to work unit. These outcomes support implementation of a flexible and targeted approach to heat stress management in large and diverse organizations in which employees are routinely exposed to heat.
本研究评估了一家全州范围的电力分销商的工人自我报告的热应激症状，以确定年龄组、地理工作区域和工作单位之间的风险差异。在总共 3250 名工人中，有 918 名（约 28%）户外员工完成了在线调查，该调查评估了工作和工作后环境中自我报告的热应激症状的频率、导致症状的因素以及症状管理。根据症状的严重程度和频率，将热应激症状分为慢性低度病例和孤立性高度病例。计算员工被归类为慢性低度或孤立性高度病例的风险（可能性），并与所有类别平均风险进行比较，以确定风险差异，用-1.00 到 1.00 表示。对于慢性低度病例，41-50 岁年龄组的风险显著增加（+0.08，p<0.05），而 60 岁以上年龄组的风险显著降低（-0.14，p<0.05）。三个区域中的两个（p<0.01）和九个工作单位中的三个（p<0.01）也表现出慢性低度病例的风险差异。工作单位是唯一表现出孤立性高危病例风险差异的分组。暴露于高温和对防护服要求较高的工作单位，如地下（+0.19，p<0.05）、架空-主要是架空线路（+0.18，p<0.01）和架空-配电和输电（+0.11，p<0.05），报告热应激症状的风险更高。本研究表明，电力行业自我报告的慢性低度热应激病例模式与孤立性高度病例不同。年龄、地理位置和工作单位独立改变慢性低度热应激的风险，而孤立性高度热应激的风险仅与工作单位有关。这些结果支持在经常暴露于高温的大型和多样化组织中实施灵活和有针对性的热应激管理方法。
