Prevention and management of heat-related illness at mass gatherings: risk assessment tool

Extreme heat is an increasing health, safety and operational risk for mass gatherings. It can cause heat-related illness, worsen chronic disease, increase demand for medical and emergency services, affect workers and volunteers, disrupt crowd operations, and place pressure on local health systems. Heat stress risk is greatest when large numbers of people are exposed for prolonged periods, especially in outdoor, crowded or constrained settings where access to safe water, cooling, transport or medical care is limited.

This document and the Risk Assessment Tool (https://doi.org/10.2471/B09844) provide a practical heat-health risk management package for mass gatherings. This document explains the “why” and “what” (evidence, principles, framework).

The Risk Assessment Tool is a standalone spreadsheet tool designed to support rapid, structured and repeatable assessment of heat-related risks before and during an event, delivering the “how” (the operational aspect). The guidance provided in the two publications should be applied across the full mass gathering event lifecycle and across the three phases used in World Health Organization health risk management: preparation, impact mitigation and recovery.