Overview

• Race director Rui Marques issued the declaration for Singapore after official forecasts showed the heat index exceeding the 31°C trigger during the event.
• Teams must fit each car with a working driver-cooling system, including pumps, a coolant reservoir and a heat exchanger, regardless of vest use.
• Drivers may decline the cooling vest, but any non-user must carry 0.5kg of cockpit ballast to preserve weight parity.
• Feedback on the system remains mixed: George Russell reported clear benefits from a Bahrain trial, while Carlos Sainz cautioned that current setups may not last a full two-hour race.
• The rule follows heat-related illnesses at the 2023 Qatar Grand Prix, and multiple reports indicate the vests are set to become mandatory in hot conditions next season.