Occupational heat-related illness risk screening protocols for aviation: a systematic review

Aircrew are subject to thermal stress and heat-related illness (HRI). Published screening methods and safety thresholds remain limited. The objective of this review was to evaluate the available evidence, approaches and guidelines regarding HRI screening tools in aircrew and analogue occupational and athletic cohorts to create a broad compendium of relevant tools for aviation safety decision-makers which establish risk stratification.

A systematic literature review was conducted through 28 July 2025, of manuscripts and technical documents that reported HRI risk screening approaches. Pairs of independent reviewers selected studies and appraised risk of bias.

Ovid MEDLINE and Epub Ahead of Print, In-Process & Other Non-Indexed Citations and Daily, Ovid EMBASE, Ovid Cochrane Central Register of Controlled Trials, Ovid Cochrane Database of Systematic Reviews and Scopus were searched.

Extrinsic and intrinsic factors checklists, protocols, diagrams, algorithms and screening approaches for HRI risk stratification and safety thresholds within occupational settings were included. Cohorts under 18 years of age and abstracts were excluded.

3472 reports were identified and 37 were included in the final analysis. Common approaches relied on wet bulb globe temperature (WBGT), workload assessment and personal protective equipment used. WBGT thresholds ranged 27-32°C for extreme risk and 23-31°C for high risk. Identified tools used 19 common domains to establish risk. Data were insufficient to identify a singular ideal screening approach.

This systematic review addresses knowledge gaps regarding occupational HRI risk screening protocols for use towards aviation workers. Limitations included lack of generalisability, risk definition variability and conflicting published author assumptions regarding intrinsic factors considered.