Bahrain Grand Prix in Malaysia declared a heat-hazard race

The Bahrain Grand Prix in Malaysia was declared a heat-hazard race on Wednesday, 30 September, ahead of Sunday’s Formula 1 race at Sepang International Circuit. The decision requires teams to fit working driver cooling systems as forecasts point to a heat index above the threshold in the 2026 regulations. Drivers can still choose whether to wear the cooling equipment.

RacingNews365 reports that the FIA made the declaration under Article B1.5.10 after its Official Weather Service predicted a heat index greater than 31.0°C during the race. BBC Sport also reported the designation, saying it is the third of the 2026 season after the Austrian and Italian Grands Prix. The heat index accounts for the effect of humidity as well as air temperature, making the forecast especially relevant at Sepang.

What the heat-hazard declaration requires

Under the FIA’s 2026 sporting rules, competitors must fit the components of the Driver Cooling System to their cars for a race covered by a heat-hazard declaration. The system must be functional and available for use. Formula 1’s explanation of the equipment describes a pump, plumbing and thermal store that send cooled fluid through tubes in a fireproof vest worn beneath a driver’s overalls.

A driver may decide against wearing the personal equipment, but the rest of the system, including its cooling medium, must remain fitted. The rules also specify mass and ballast provisions when a driver opts out, alongside a five-kilogram Heat Hazard Mass Increase for a covered race session. That does not mean every driver who declines the vest simply adds five kilograms of ballast: the regulations account for the weight through driver equipment and cooling-system components.

Why Sepang poses a demanding test

Sepang combines tropical heat and humidity with a circuit that asks drivers to work through long straights, heavy braking zones and fast corners, according to RacingNews365. Its 5.543-kilometre layout can also be affected by rapidly developing thunderstorms. Formula 1’s weekend forecast includes a chance of rain on each of the three running days, so teams face both heat management and potentially changing track conditions.

BBC Sport says the temperature inside a Formula 1 cockpit can exceed 40°C. Drivers also race in layers of fireproof clothing, a balaclava and a helmet. Those conditions help explain why cooling is a concern even when the forecast air temperature is lower than the heat index. The designation provides a way to have equipment ready across the field while leaving use of the wearable part to individual drivers.

How the cooling rule developed

Formula 1 says the FIA began examining ways to manage extreme race conditions after the high temperatures and humidity of the 2023 Qatar Grand Prix. A heat-hazard declaration was introduced ahead of the 2025 season. The process allows the governing body to act on a pre-race forecast; the regulations also give the race director discretion to declare a hazard. Austria and Italy have already received the designation this year, according to BBC Sport.

Whether a driver wears the vest remains a practical choice. In Formula 1’s earlier explanation of the rule, McLaren driver Oscar Piastri said a working system could help, but described its reliability and design as imperfect. He said its use came down to personal preference. The available reports do not establish which drivers will use the vest at Sepang or how the systems will perform over Sunday’s race distance.

This event carries the Bahrain Grand Prix name but is being staged in Malaysia. BBC Sport reports that the race was moved from its original April date because of the war in the Middle East. For this weekend, the immediate consequence of the heat-hazard decision is clear: cooling systems must be installed and available, while each driver decides whether to wear the vest as the forecast conditions approach.