FIFA heat-safety concerns raised by scientists ahead of 2026 World Cup

FIFA said it would implement protections for fans, including allowing factory-sealed water bottles, and activating cooling measures such as shaded areas, misting systems, cooling buses and expanded water distribution.

FIFA declined to comment directly on the letter or the scientists' claims.

Researchers warned that around a quarter of matches could be played above 26C WBGT and about five games could exceed 28C WBGT (roughly 38C in dry heat or 30C in high humidity). The WWA notes risk has nearly doubled since 1994 due to climate change.

Scheduling has been designed with climate in mind: kick-off times adjusted to avoid hottest periods, matches during the hottest periods limited, warmer fixtures prioritised for covered stadiums, and travel and rest days planned based on heat risk assessments.

FIFA said it would use a "tiered heat mitigation model" with real-time monitoring, dedicated meteorological support, and WBGT/heat index data to inform decisions.

"The hydration break in each half absolutely needs to be longer than three minutes - at least five minutes for each break and preferably six," said Professor Douglas Casa of the University of Connecticut as part of the letter's commentary.

The scientists urged FIFA to adopt standards proposed by Fifpro, the global players' union.

An open letter signed by 20 world-leading scientists claims FIFA's heat safety measures for the 2026 World Cup are "inadequate" and "impossible to justify", urging stronger protections including longer cooling breaks and clearer protocols for delaying or postponing games.

Hot conditions at the 2025 Club World Cup in the United States tested the players.