dry ice

The system, which teams can make to their individual designs, typically features a liquid such as glycol pumped through a tank of dry ice and through the driver's fireproof top.

Issues with the system include the dry ice running out.

Teams design their own cooling systems but most are similar - a tank of dry ice through which a liquid such as glycol is pumped before running through a tube in a vest worn by the driver.

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.

In reality, he had used ice and dry ice to freeze his own legs, causing damage that meant they eventually had to be amputated in hospital.