Occupational Heat Stress Prevention Interventions: A Scoping Review of Evidence and Gaps.

BACKGROUND: Rising temperatures are exacerbating occupational heat stress globally, disproportionately affecting workers in resource-constrained settings in low- and middle-income countries (LMICs). While prevention strategies have been evaluated, the evidence remains scattered, limiting its utility for policy and practice. OBJECTIVES: This scoping review aimed to outline occupational heat-stress interventions, summarize current evidence, and identify gaps in feasibility, cost-effectiveness, and implementation across various work settings. METHODS: We conducted a search of Embase, PubMed, and Scopus until June 2025, adhering to the Joanna Briggs Institute (JBI) methodology and PRISMA-ScR guidelines. Two reviewers independently evaluated studies using Covidence. Descriptive statistics and thematic analysis synthesized data regarding interventions, settings, outcomes, and implementation. RESULTS: Out of 1847 records, 90 studies were included: Work practice and administrative controls (6), wearable cooling (clothing and cooling garments) (34), active and passive cooling (31), rehydration (15), and engineering controls (4). Most studies (73%) were conducted in developed countries and controlled laboratory settings (68%), revealing a significant evidence gap in LMICs, the informal sector, and vulnerable populations. Studies primarily assessed immediate physiological outcomes rather than long-term health, productivity, or cost-effectiveness. Wearable monitoring and Health (Mobile health) emerged as promising areas for future evaluation. CONCLUSION: This review reveals a significant evidence gap: most interventions are studied in laboratory environments, whereas field-based effectiveness data remain limited. Future research should prioritize intervention trials that employ participatory methods, cost-effectiveness analyses of scalable solutions, and implementation studies that address barriers to field adoption. Translating laboratory findings to field settings is urgently needed to protect vulnerable workers amid escalating climate change.