For the first time in Formula 1 history, drivers will be competing under the FIA’s newly introduced ‘Heat Hazard’ regulations, which make driver cooling kits compulsory equipment on the cars.
The move marks a turning point in the sport’s approach to extreme weather, safety, and performance.
The spotlight will not only shine on the 20 drivers strapped into their cockpits but also on the liquid-cooled vests humming beneath their race suits — a technology designed to keep them alive, alert, and able to race at the limit.
Singapore has always been infamous on the F1 calendar for its punishing conditions.
Even though it is a night race, humidity clings to the track like a blanket, often reaching more than 80 percent, while ambient temperatures hover around 30–32 °C.
Inside a Formula 1 cockpit, where heat from the hybrid power unit, braking systems, and sealed bodywork builds relentlessly, conditions can climb to 50–60 °C.
This year, the FIA officially declared Singapore 2025 as the first race under its Heat Hazard protocol.
Forecasts for trackside conditions triggered the threshold — ambient above 31 °C and humidity at critical levels — making it mandatory for every team to fit the FIA-approved cooling systems.
While drivers may still opt out of wearing the vest itself in 2025, they must carry ballast equivalent to its weight, eliminating any competitive advantage.
The roots of this weekend’s new regulation stretch back two years to the 2023 Qatar Grand Prix. That race, run in blistering heat, became notorious after multiple drivers suffered heat exhaustion.
Esteban Ocon vomited inside his helmet mid-race but continued driving; Logan Sargeant was forced to retire after feeling physically unable to continue; Lance Stroll later admitted he nearly blacked out in high-speed corners.
The incident prompted an outcry from the Grand Prix Drivers’ Association (GPDA), which argued that the sport had underestimated the dangers of modern race calendars in hot, humid regions.
The FIA agreed, launching a medical review into heat stress, hydration, and cockpit design. The result was the creation of a standardized cooling system, with strict technical requirements written into the Formula 1 Technical Regulations for 2025 and beyond.
The FIA kits are essentially liquid-cooled vests worn under the fireproof race suit. They work by circulating chilled fluid — typically water or a saline solution — through a network of thin tubes sewn into the fabric.
The fluid either comes from a small cooling reservoir or uses stored thermal energy packed with ice-like material that absorbs heat during the race.
The FIA has set precise performance standards:
A system must be able to extract at least 200 watts of heat from the driver’s body at 40 °C ambient conditions.
If based on stored cooling, the system must hold a minimum energy reserve of 1.1 megajoules.
Only safe fluids like water, sodium chloride solution, or propylene glycol are permitted.
Hazardous substances — such as dry ice — are strictly banned from cockpits.
Any refrigerant used must have a global warming potential under 10, aligning with the sport’s sustainability goals.
This is not optional technology slapped together by teams. The FIA homologates the suits, fluids, and hardware itself to ensure both effectiveness and safety.
Drivers have already been experimenting with the vests during the hotter rounds earlier this year. George Russell ran one at the Bahrain Grand Prix, while others tested them in practice sessions. Reactions, however, have been mixed.
Some, like Russell, see them as a welcome safety net, especially in long, high-intensity races where cockpit heat can impair concentration. Others are unconvinced. Lewis Hamilton, now with Ferrari, has publicly expressed skepticism, saying preparation and conditioning should remain the priority rather than reliance on extra equipment.
Esteban Ocon, racing for Haas, has gone further, calling the kit “unusable in its current form” due to comfort and fitting issues inside the cramped cockpit. Oscar Piastri at McLaren and Lance Stroll at Aston Martin also commented earlier this year that the design “needs more work.”
For them, the added bulk and awkwardness may outweigh the perceived benefits — especially if the system interferes with seating position, belts, or steering precision.
The FIA anticipated such resistance. That is why, in 2025, use of the vest remains optional even when fitted — though ballast rules ensure no team can gain a weight advantage by leaving it behind.
From 2026, however, drivers will have no choice but to wear the vest when a Heat Hazard is declared.
The question of comfort is at the heart of the debate. Formula 1 is a sport defined by margins — a poorly placed strap or an extra kilogram of weight can mean the difference between pole and the midfield. Yet the FIA’s medical commission argues that the risks of heatstroke, dehydration, and cognitive decline during races are too great to ignore.
In extreme heat, a driver’s core body temperature can rise past 39 °C, impairing reflexes and decision-making. At 300 km/h, that’s a recipe for disaster. The cooling kits are meant as an insurance policy to keep drivers safe enough to race hard without risking collapse.
Singapore’s designation as the first Heat Hazard race is symbolic of broader trends. Formula 1’s global expansion has taken it deeper into regions with hot and humid climates: Qatar, Saudi Arabia, Miami, and Abu Dhabi all present conditions ripe for heat stress.
Add to that the sport’s longer seasons and tighter turnaround between races, and the FIA’s intervention starts to look less like overreach and more like a necessity.
This move also aligns with Formula 1’s ongoing efforts to project an image of sustainability and driver welfare.
Just as headrest design, HANS devices, and halo cockpits became once-controversial safety innovations that are now standard, the cooling vest is simply be the next step in the sport’s evolution.
So, how will this play out under the lights of Marina Bay?
All 20 cars will run the FIA-approved system.
Some drivers will elect to wear the vest, while others may continue without, accepting the ballast penalty instead.
The FIA’s medical team will closely monitor hydration levels, weight loss, and post-race health data.
Teams will be gathering feedback on the vest’s ergonomics, fluid endurance, and how it interacts with pit stop routines.