New Formula 1 rule introduces cooling systems to help drivers handle extreme heat

The first race of the 2025 Formula 1 season saw McLaren's Lando Norris take victory at a wet and wild Australian Grand Prix on the weekend in Melbourne.

But even in the relative cool of Sunday afternoon, drivers felt the heat. Formula 1 racing is awfully hot work at the best of times.

From 2025, a new rule means Formula 1 cars must be fitted with a cooling system for races on days when the sport's governing body declares a heat hazard.

So why has this system been implemented, and what other health risks do drivers contend with on race day?

High heat even when it's cool outside

The dangers of extreme heat for Formula 1 drivers were thrust into the spotlight after the 2023 Qatar Grand Prix.

The race was held at night, but even so, track temperatures hovered around 36 degrees Celsius and humidity remained high.

After the race, drivers struggled to get out of their car due to the hot, muggy conditions. Esteban Ocon vomited in his helmet while driving, and Lance Stroll felt himself passing out in the car.

"You're dizzy, it's dark, you're fading with low blood pressure," Stroll said in a sweaty post-match interview.

Despite being open to the air around them, a cramped Formula 1 car cockpit can get super-hot, Justin Holland, and exercise physiologist at Queensland University of Technology, says.

In research with V8 Supercar drivers on Phillip Island, even on a relatively cool day when the outside temperature is around 16–24C, the mercury can reach the mid 30s inside the car, and even higher in the footwell where the pedals and braking system are.

And with heat comes sweating and dehydration — and the risk of fatigue, which itself can be dangerous, Dr Holland says.

So from this year, for Formula 1 competitions where the forecast temperature will reach 31C, or at the discretion of the race director, a "heat hazard" can be declared.

When that happens, cars must be fitted with a cooling system. The system comprises a box of components, including a condensation unit, and a vest that circulates cool liquid in tubes for drivers to wear under their gear if they wish.

As of 2026, wearing the vest will be mandatory for races when a heat hazard is declared.

While the cooling system should help with driver comfort, air temperature is just one factor in heat stress. Humidity, wind speed, and the heat of the Sun beating down all contribute to Formula 1 cockpit heat stress, but aren't included in the new regulations.

"We do need to consider these other factors," Dr Holland says.

"As soon as the humidity rises, our body's ability to donate or or lose water to the environment is reduced."

G-forces put big strain on drivers

Hurtling around a track in an exquisitely engineered speed machine has other risks, such as G-forces, short for "gravitational forces equivalent".

Whenever a driver accelerates, brakes or turns a corner, they feel like they're being forced back into their seat, pulled forward, or pushed to one side.

When a Formula 1 car takes a long, sweeping corner at a few hundred kilometres an hour, this can generate a force of up to 5 Gs on the driver, meaning the driver will experience a force equivalent to five times their body weight.

For instance, Oscar Piastri, who weighs around 70 kilograms, would experience a force of around 350kg on his body (that's equal to the weight of four adult kangaroos).

G-forces can put enormous strain on a driver's neck, which not only must support their head, but their helmet too.

So drivers spend time building up their neck muscles so they're better able to withstand G-forces, especially lateral forces that come with taking corners at speed, and forward movement that comes with braking.

Helping drivers on this front are head and neck support — or HANS — devices.

They look like big horseshoes worn around their shoulders, which clip onto the helmet and stop it moving too much during races.

This device, as well as the many other safety features such as seatbelts, also restrain the driver in the event of a crash.

What if there's a crash?

While racing teams have their own doctors and medical crew, each Grand Prix race also has a medical team on hand.

Jack Spencer is an emergency physician at Alfred Health who heads the Australian Grand Prix medical team.

The medical centre has an ultrasound, a portable X-ray, and "all the machines that go bing", he says.

Luckily, he and his colleagues haven't had to tend to too many bad bingles on the Albert Park track in the 23 Australian Grands Prix he's worked at.

"Any driver that gets disabled by impact is supposed to come here for clearance to race again," Dr Spencer says.

If a driver is assessed on the track to be in a serious condition, they'll be put in an ambulance and driven directly to the Alfred Hospital, which is only a few minutes' drive away.

Dr Spencer and his team mostly tend to the people around the drivers — such as race marshals, employees, corporate staff — for "mundane stuff" like blisters and sprained ankles.

"Most of the real serious stuff we get with track-side people is … heart attacks, arrhythmias," he says.

Lighter cars in 2026 mean more demands on drivers

Along with mandatory cooling systems, another rule change in 2026 affects the cars themselves, which will be allowed to be lighter and more nimble.

This means they'll be faster — not just on the straights, but also when cornering, Dr Holland says.

"So not only is there going to be greater G-forces … on drivers, there's also going to be an increased cognitive demand on them.

"If we think about it, you're going into a corner, maybe 250–300kph, and you're trying to overtake someone, you need to be very cognisant of where that other car is.

"So we're going to see greater physical demands on drivers come 2026."

For more on Formula 1 driver health, listen to the full episode of Lab Notes.