An exploratory survey of on-site heat stress management practices in the Canadian mining industry

With climate change fueling more frequent and intense periods of hot weather, heat stress management programs are becoming increasingly important for protecting the health and safety of workers in the Canadian mining industry. While the inclusion of heat-mitigation measures such as those provided by the American College of Governmental Industrial Hygienists (ACGIH) Threshold Limit Values (TLVs) are commonly employed by industry, there is a need to develop more comprehensive industry-specific measures for heat stress prevention and management. To better understand current heat management practices and identify opportunities for improvement, an exploratory survey of 51 employees responsible for health and safety at underground mining (n = 35), and surface operations (n = 16) (e.g., open-pit mining, milling, smelting, and exploration site) was conducted in Canada. The respondents answered 50 questions related to workplace heat stress management, including descriptors of the workplace environment, perceived heat stress hazard, administration of heat stress management programming, heat stress emergency procedures, environmental monitoring strategies, and knowledge of mining-specific regulations related to heat stress. Twenty-four managers (47%) reported that heat-related illnesses led to restricted duty or lost time claims at their site, with a median of 5 [IQR: 2–10, max: 30] reportable heat-related illnesses occurring per site annually. Many also felt that heat-related illnesses are under-reported by their workforce (n = 36, 71%). Most sites reported established heat stress management programs to prevent heat illness (n = 43, 84%), typically based on the TLVs (n = 38, 75%). Although some organizations do conduct pre-task evaluations for heat stress (n = 30, 59%), more than half do not conduct post-job evaluations (n = 28, 55%) or pre-employment screening for heat stress vulnerability (n = 3, 6%). While our findings indicate that the health and safety managers recognize the hazard posed by heat and have stated practices to help address the hazard, we also observed inconsistencies in heat stress management programming across the sample. Developing and adopting a standard heat stress management and reporting system would be an important step toward protecting workers from existing and emerging threats from extreme heat and climate change.随着气候变化导致高温天气愈发频繁且强度升级，热应激管理方案对于保障加拿大矿业从业人员的健康与安全正变得愈发重要。尽管行业内普遍采用美国政府工业卫生学家协会（American College of Governmental Industrial Hygienists, ACGIH）提出的热接触极限值（Threshold Limit Values, TLVs）相关的降温措施，但仍需开发更具针对性的矿业专属热应激预防与管理方案。为更好地了解当前热应激管理实践并识别改进空间，研究团队在加拿大开展了一项探索性调研，共访谈51名负责地下采矿（n=35）与露天作业（n=16，包括露天采矿、选矿、冶炼及勘探场地）的健康与安全专员。受访人员需完成50道与作业场所热应激管理相关的问卷题目，内容涵盖作业环境描述、感知热应激危害、热应激管理方案实施情况、热应激应急流程、环境监测策略，以及矿业专属热应激相关法规认知情况。24名管理人员（占比47%）反馈，其所在场地因热相关疾病出现了受限作业或误工索赔案例，各场地每年上报的热相关疾病中位数为5例[四分位距（IQR）：2–10，最大值：30]。另有36名受访者（占比71%）认为，其作业团队存在热相关疾病漏报情况。多数作业场地已设立热应激管理方案以预防热相关疾病（n=43，占比84%），其中75%（n=38）的方案以TLVs为制定依据。尽管部分机构会开展热应激作业前评估（n=30，占比59%），但超过半数机构未开展作业后热应激评估（n=28，占比55%），也未针对热应激易感性进行入职前筛查（n=3，占比6%）。尽管调研结果显示，健康与安全管理人员已意识到高温带来的危害并制定了相应的应对措施，但样本中各机构的热应激管理方案仍存在不一致性。制定并推行统一的热应激管理与上报体系，将是保护从业人员免受极端高温及气候变化带来的现有与新兴威胁的重要举措。