Weak FIFA World Cup heat safety guidelines “impossible to justify” say leading health experts

Leading experts in health, climate science and sports performance have signed an open letter urging FIFA to strengthen heat protections for players at the men’s 2026 World Cup, warning that current safety guidelines are “impossible to justify.”

The tournament, hosted across 16 cities in the United States, Mexico and Canada, is expected to expose players to dangerous levels of heat and humidity, with some venues likely to exceed internationally recognised “high risk” thresholds.

The signatories - including leading physiologists, climate experts and sports medicine academics from across Europe, North America and Australia - warn that FIFA’s current rules lag behind global health and labour standards.

Under existing guidelines, matches may continue until Wet Bulb Globe Temperature (WBGT) levels exceed 32°C. The letter calls instead for cooling breaks above 26°C WBGT and match delays or postponements above 28°C.

Professor Mike Tipton, President of The Physiological Society, warned that extreme heat can cause “impaired performance” and potentially fatal heat stroke, particularly during afternoon kick-offs intensified by climate change.

Heatwaves are becoming more frequent and more intense as a result of climate change, which is caused primarily by the burning of fossil fuels. The letter warns FIFA that its “active promotion” of fossil fuels, referring to a controversial sponsorship deal with Aramco, the world’s largest producer of oil, represents “a conflict of interest with the protection of player welfare”.

The 2026 World Cup will be the most carbon polluting ever owing to its expansion to 48 teams and 16 cities in three countries, requiring a large increase in air travel by fans and players. 

Beyond the tournament’s direct emissions, the letter also highlights FIFA’s sponsorship deal with oil giant Aramco, arguing that the “active promotion” of fossil fuels represents “a conflict of interest with the protection of player welfare.”

The authors describe the 2026 World Cup as a defining moment for global sport in the climate crisis, warning that rising temperatures are already affecting athletes across multiple sports.