The HEAT-SHIELD project - Perspectives from an inter-sectoral approach to occupational heat stress.

OBJECTIVES: To provide perspectives from the HEAT-SHIELD project (www.heat-shield.eu): a multi-national, inter-sectoral, and cross-disciplinary initiative, incorporating twenty European research institutions, as well as occupational health and industrial partners, on solutions to combat negative health and productivity effects caused by working on a warmer world. METHODS: In this invited review, we focus on the theoretical and methodological advancements developed to combat occupational heat stress during the last five years of operation. RESULTS: We outline how we created climate forecast models to incorporate humidity, wind and solar radiation to the traditional temperature-based climate projections, providing the basis for timely, policy-relevant, industry-specific and individualized information. Further, we summarise the industry-specific guidelines we developed regarding technical and biophysical cooling solutions considering effectiveness, cost, sustainability, and the practical implementation potential in outdoor and indoor settings, in addition to field-testing of selected solutions with time-motion analyses and biophysical evaluations. All recommendations were adjusted following feedback from workshops with employers, employees, safety officers, and adjacent stakeholders such as local or national health policy makers. The cross-scientific approach was also used for providing policy-relevant information based on socioeconomic analyses and identification of vulnerable regions considered to be more relevant for political actions than average continental recommendations and interventions. DISCUSSION: From the HEAT-SHIELD experiences developed within European settings, we discuss how this inter-sectoral approach may be adopted or translated into actionable knowledge across continents where workers and societies are affected by escalating environmental temperatures.

Direct exposure of the head to solar heat radiation impairs motor-cognitive performance.

Health and performance impairments provoked by thermal stress are societal challenges geographically spreading and intensifying with global warming. Yet, science may be underestimating the true impact, since no study has evaluated effects of sunlight exposure on human brain temperature and function. Accordingly, performance in cognitively dominated and combined motor-cognitive tasks and markers of rising brainstem temperature were evaluated during exposure to simulated sunlight (equal to ~1000 watt/m2). Acute exposure did not affect any performance measures, whereas prolonged exposure of the head and neck provoked an elevation of the core temperature by 1 °C and significant impairments of cognitively dominated and motor task performances. Importantly, impairments emerged at considerably lower hyperthermia levels compared to previous experiments and to the trials in the presents study without radiant heating of the head. These findings highlight the importance of including the effect of sunlight radiative heating of the head and neck in future scientific evaluations of environmental heat stress impacts and specific protection of the head to minimize detrimental effects.