Haas driver Oliver Bearman has led calls for FIA to fine-tune its regulations around the new cooling vests that drivers have at their disposal for hot Formula 1 races.
In the wake of an extremely hot 2023 Qatar Grand Prix in which several drivers struggled with varying heat exhaustion symptoms, the FIA has worked to introduce driver-worn cooling vests for this year.
Drivers are free to run with the vest whenever they want, but if the ambient threshold exceeds 31C on the Thursday of a grand prix weekend, the weight limit will be increased by 5kg as an allowance for teams to install the device without any weight penalty. For 2025, drivers can still opt out, but will then have 500g of ballast added to the cockpit area to ensure fairness.
What has been more divisive is the use of the device when that heat index has not reached 31C and drivers would still like to run the vest anyway. In that case the weight limit isn’t increased, benefitting teams who have been able to get well below the mandated 800kg minimum limit and have ballast to take out. That situation has been the case at every race thus far this season, with even Jeddah’s Saudi Grand Prix not triggering the threshold because temperatures were lower on Thursday than they were on race day.
“The whole cooling system is heavy. We’re trying to get the most performance out of the car. We’re not trying to make the car lighter to run the cooling vest,” Haas driver Bearman said after running the system in practice, but then having to take it off for the race to save weight.
“Unfortunately, we’ll have to suffer a bit until they hopefully change something to allow us to run it a bit more freely, because at the moment clearly some teams have the margin to run it. The fact that some teams are able to run it and some aren’t, that for me is something that needs to change there. If they’re never going to declare it hot enough, then only half the teams are getting the benefit.”

George Russell, Mercedes
Photo by: Peter Fox / Getty Images
One solution would be to either lower the threshold, an idea which Bearman’s team boss Ayao Komatsu backed, as did Mercedes driver George Russell who has been able to race the device. “Maybe the heat hazard should be reduced slightly because we’ve not yet gone over it,” said Russell. “Saudi was hot, Bahrain was hot, here [in Miami] – maybe it could be adjusted by a few degrees.”
But Motorsport.com understands the FIA is satisfied with the current threshold of 31C, and instead of lowering it the preferred option is to use the weather forecast on race morning to assess whether the threshold will be met instead of having to use less accurate four-day predictions on Thursday. That was the original idea, but teams are understood to have pushed back against it as it would force them to make late changes to their cockpit set-ups.
Tinkering with weight limits seems off the table, as teams being able to shave off enough weight to install the device without penalty could be considered an engineering success rather than an unfair advantage.
The cooling vests have received mixed reviews from drivers, with the latest version being given the thumbs up by both Bearman and Russell while others are more reluctant. “I feel fortunate that I’ve had the chance to run with the cooling vest. It’s not perfect yet, but it’s definitely an improvement,” Russell said.

Oliver Bearman, Haas F1 Team
Photo by: Peter Fox / Getty Images
Bearman added: “I tried it in Jeddah. It seemed really, really good. So, I’m really happy with what they’ve been able to do to roll that out, and actually that it’s been successful and quite useful.
“You do feel it a little bit, especially on your back because you’re pushed up against the seat. But honestly, the benefit of having cool water, even if it just works for 10, 15, 20 laps of the race, I think it’s game-changing.
“What you don’t see is the humidity. The [ambient temperature] may be 27, 28, 29 degrees, but with 60 or 70 percent humidity – with all those layers on – it’s really, really hot. And having cool water is life-changing. It really helped me in a few practices. Unfortunately, we weren’t able to run it in the race, but it was quite good. The original design didn’t work for anyone. Now it works pretty well.”
It is understood the FIA is still planning to make the cooling vests mandatory in hot races from next season onwards, with teams now having the rest of the season to further test the system in practice and refine their cockpit installations.
Photos from Miami GP – Practice
In this article
Filip Cleeren
Formula 1
Oliver Bearman
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