F1 cooling vests explained: How they work, what they cost and why Mercedes said no

With F1's fourth heat hazard weekend of the season approaching fast at the Singapore Grand Prix, at least two drivers won't be availing themselves of cooling vests inside their roasting cockpits.

George Russell revealed last weekend in Malaysia that Mercedes 'haven't put the resource into making it robust enough', explaining that the team didn't have the money to develop the system under the cost cap this year.

The Brit was famously among the drivers - with then-Mercedes team-mate Lewis Hamilton - who suffered 'borderline heatstroke' in Singapore two years ago, and he admitted in Malaysia that he would prefer to be wearing a cooling vest system this weekend.

The temperatures are forecast to be in the low-to-mid 30s this weekend at the Marina Bay circuit, with the intense humidity making it feel closer to 40 degrees Celsius. In other words, a bad time to be sat on top of a red-hot F1 engine.

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What are F1 cooling vests and how do they work?

As the name suggests, they're vests for F1 drivers to wear in their race suits which help cool them down.

The vests have a series of thin tubes stitched into them, through which cool liquid is pumped over the course of the race to help lower the wearer's core temperature.

However, there are some issues with the system. Some drivers claim that they're uncomfortable, with the thick material and tubing a little heavy under already hefty fireproofs.

There's also the issue of what happens if and when the vest fails. This is something seen countless times a year in NASCAR, where cooling vests are more commonly worn, and can essentially result in the water/cooling fluid staying in the vest rather than cycling through, while it gets hotter and hotter.

That, given how hot the inside of an F1 car can get (some drivers famously refer to their drinks bottles as being like a cup of tea by mid-race), is substantially worse than not having the vest on at all. If the cooling system fails, things get incredibly uncomfortable.

How much do F1 cooling vests cost?

It's unclear, but the FIA and Mercedes' actions have suggested that the cost of developing and producing a functioning cooling vest system for an F1 team is likely in six figures.

Are F1 cooling vests included in the cost cap?

The cost of F1 cooling vests is included in the cost cap, which is the dilemma Mercedes faced this season. Pour that crucial little bit more money into car development? Or put it into cool suit development?

Russell said last week: "I feel we need the FIA just to step in and say, 'Here's some money extra in the cost cap', or there's an external company who's going to develop it for everybody, you just put the money towards it. Because we should all be wearing it."

However, the FIA have at least tried to help the process along somewhat.

How much is the FIA offering teams for cooling vests?

While the FIA are reluctant to move cooling vest development outside the cost cap, they have made some concessions. If a team creates a cooling system which can last the full race distance, they will be granted an extra $50,000 allowance under the cap.

Furthermore, if that vest actually works well enough to solve driver comfort issues, there's another $75,000 on the table.

However, it's on the teams to prove that their systems actually work in simulator or practice sessions if they're to get the extra allowance.

Why have Mercedes decided against F1 cooling vests?

No guesswork necessary for this one. Mercedes deputy team principal Bradley Lord has explained: "There was a small allowance that was made. We didn't believe that allowance was sufficient for us to be able to develop a solution that would be robust enough to last for the entire race."

With very few races expected to be hot enough to make cooling vests worth having, the team decided to focus their attention elsewhere.

Lord added: "The overall cooling in the cockpit of the car is in a much better place than it was a couple of years ago when both George and Lewis at the time struggled so badly in Singapore.

"In terms of the overall trade-off, the drivers are always happy if we're looking to trade something that ultimately is a comfort factor versus pure performance. They, like all the rest of us and like every racer up and down the pitlane, will take performance over comfort."

Are F1 cooling vests mandatory?

No, cooling vests are not mandatory at F1 races, no matter the temperature.

However, if a heat hazard is declared then teams will be given the option to either use their cooling vest systems or race with ballast added to their car, in order to make sure that the use of a cooling vest is not a disadvantage – removing any temptation for teams to sacrifice driver health for performance.

Why are F1 cooling vests important at the 2026 Singapore Grand Prix?

Because it is going to be hot. Despite the race taking place at night, temperatures are expected to be up in the 30s, with the extreme humidity pushing the heat index several degrees higher again.

That would be unpleasant at the best of times, but F1 drivers are sat just a hair's breadth from an engine that runs at over 100 degrees Celsius, and are performing very strenuous activities. It's better to do that without getting heat stroke.

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Written by

Chris Deeley - Editor

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