Overview

• Race director Rui Marques confirmed the designation after forecasts showed the Heat Index at or above the 31°C threshold during the Singapore weekend.
• All cars must be equipped with pumps, plumbing, a coolant reservoir and a heat exchanger, while drivers may choose whether to wear the coolant vest.
• Drivers who forgo the vest must carry 0.5kg of cockpit ballast to prevent any weight advantage over those who use it.
• Cars must run heavier under the policy, with reports citing an extra 2kg for practice and qualifying and 5kg for the sprint or Grand Prix.
• The rule follows heat-related incidents in Qatar 2023, with drivers noting Singapore’s extreme humidity, cockpit temperatures approaching 50–60°C and typical fluid loss of around 2–3kg during the race.