Verstappen said he felt the system and the rules that come with it were flawed.
“I haven’t used the vest,” he said. “I’m also not intending to use it. Because I feel like this needs to be the driver’s choice.
“From the FIA side, they will always throw it on safety. But then we can talk about a lot of stuff that can be improved on safety, including pit entries in certain places. I think that has a bit more priority than a vest in the car.
“I don’t like it. I don’t like the tubes that are on you and your body with the belts that go next to you. Then they can say it’s a bad design. I disagree. It just needs to be an option for the drivers to choose.
“Some like it, some don’t. And that’s fine. It should be a personal preference. I know, of course, this year we can (choose). But probably next year they don’t want to do that. And that is not the right thing.
“The problem also is that in a GT car or any other car, prototype, you have a bit more space to put stuff, or at least cables.
“In our cockpits, it’s so narrow that there is no space, or at least not enough space. And that is also a little bit of a problem I find.
“Plus, where are you going to put the dry ice? The cars are not designed really to have this extra kind of space. And within 15, 20 laps, it’s anyway gone. And you have hot water (running through the system).”
Verstappen’s last remark highlights an issue with the system whereby if the dry ice cannot be kept cold for long enough, the fluid in the system takes on the ambient temperature around the tank.
As F1 cars reach temperatures exceeding 40C during races, that means the liquid pumping through the system would make the driver hotter rather than cooler.
But Russell said: “I’ll run it. I ran it in a couple of races this year. It isn’t the perfect solution yet. And the fact is, you have no testing, you can only test it in a race environment.
“So, the race in Bahrain, I was happy with it. I ran it in Saudi as well. I was happy with it. But, of course, here it is much hotter. The dry ice will melt faster.
“But the team have made big improvements with the car cooling of itself. We recognise some quite major issues of sort of hot air seeping in.
“The cockpit massively exceeded 60C at certain races and just moving a few electronic boxes around and hydraulic lines that are running at 120C around your feet have a major impact on the heat. I’ll give you an answer tomorrow (as to whether it worked).”
Championship leader Piastri said: “I still don’t know if I’m going to use it. I used it yesterday. I think the problem with the suit is it’s great when it works. But if it fails, it’s even worse than not having it.
“I think the initiative is good. But, like Max said, I think having the choice to use it or not is important because there are benefits and downsides.”
The split in the top three is expected to be reflected up and down the grid.
