Singapore Grand Prix declared heat hazard as Mercedes opt out of cooling system

The Singapore Grand Prix has been designated a heat-hazard event, making it the fourth Formula 1 race to receive that status this season, BBC Sport reported on Thursday. It is the second consecutive race weekend covered by the measure, which permits teams to install equipment designed to cool drivers while they are in the cockpit.

Watch the highlights:

The designation, introduced in 2025, applies when temperatures are forecast to exceed 31C during a race. Singapore's night-time start does not eliminate the heat: temperatures remain around 30C after dark, while high humidity adds to the demanding conditions. BBC Sport's Andrew Benson reported that daytime temperatures across the race weekend are typically in the 31-33C range, with rain possible each day.

Drivers are not required to use the cooling equipment. Those who opt out must instead carry 5kg of ballast in their cars so that declining the system does not produce a competitive advantage. The equipment circulates cooled liquid through tubing in a fireproof garment beneath the driver's racing overalls, supplied by a tank and pump generally mounted in the nose of the car.

Keeping that liquid cold for the full race remains a technical difficulty. Some drivers also find the garment uncomfortable inside the cockpit. If the system loses its ability to cool, the circulating liquid can reach the temperature of the car, rather than the outside air. According to the BBC report, cockpit temperatures can exceed 40C, making sustained cooling an important limitation of the equipment.

Mercedes have decided against using the system, preferring to direct development resources towards car performance. Benson reported that the FIA offers a $50,000 cost-cap allowance for a system capable of cooling throughout a grand prix, plus a further $75,000 for making the garment comfortable. Mercedes deputy team principal Bradley Lord said the allowance was insufficient for the team to develop a solution that would remain effective for an entire race.

The physical demands in Singapore have previously required medical attention for drivers. In 2024, Mercedes pair George Russell and Lewis Hamilton were treated for heat exhaustion after the race, the BBC reported. This year's designation again gives teams the option of fitting cooling equipment, while retaining the ballast requirement for drivers who race without it.