Protective Wearable Cooling Gear to Combat Heat Stress among Workers: A Critical Narrative Review

Abstract

Occupational heat stress has become one of the more pressing safety concerns in today's world of work. Rising ambient temperatures, increasingly frequent heatwaves, and the continued need for many workers to perform physically demanding tasks while wearing insulating protective clothing have combined to push large numbers of outdoor and indoor labourers close to the limits of human thermoregulation. Personal cooling garments have emerged as a practical, comparatively low-cost complement to engineering controls such as air-conditioning and shading, particularly where environmental modification of the workplace is simply not feasible or affordable. This review critically examines the literature on wearable cooling technologies designed to mitigate occupational heat strain, covering their underlying engineering principles, their physiological and perceptual efficacy, their performance across different occupational sectors, their convergence with physiological monitoring, and the human and organisational factors that shape whether they are actually used. The evidence suggests that conductive systems based on phase-change materials and pre-cooled liquids, together with hybrid garments combining several heat-exchange pathways, offer the most consistent reductions in core temperature and heart rate, whereas purely evaporative and radiative garments produce a smaller physiological benefit while still often improving thermal comfort. Field evidence from construction, agriculture, mining, and firefighting broadly supports laboratory findings, though with considerable variation linked to clothing insulation, workload, environmental humidity, and how long a garment is actually worn. Smart textiles and wearable physiological sensors are increasingly being used to personalise cooling delivery and to flag rising heat strain before it becomes dangerous, although this remains an early-stage technology from an occupational-validation standpoint. Persistent barriers to uptake include cost, weight, limited operating duration, and worker concerns about comfort and practicality, all of which interact with workplace culture and supervisory support. The review concludes that wearable cooling gear is a genuinely useful but imperfect tool: it reduces physiological and perceptual strain without removing the need for hydration, acclimatisation, sensible work–rest scheduling, and broader climate-adaptive labour policy.