Fire is one of the most serious hazards in Formula One. F1Technical’s senior writer Balazs Szabo explains how the highly engineered onboard fire‑suppression system works inside the F1 car.
With hybrid power units operating at extreme temperatures, high‑voltage electrical systems, and flammable fluids circulating through a tightly packaged chassis, the risk of ignition is ever‑present.
To mitigate this danger, every F1 car is equipped with a highly engineered onboard fire‑suppression system designed to protect the driver and contain fires within seconds. Although rarely seen by spectators, the extinguisher system is a critical safety component whose design reflects the sport’s uncompromising approach to risk management.
A Lightweight but Robust Pressure Vessel
At the core of the system is the fire bottle — a carbon‑fibre pressure vessel that forms the main body of the extinguisher. Inside this vessel sits a flexible bladder or balloon that contains the extinguishant, a liquid chemical stored under pressure. When released, this liquid rapidly expands into a gas, allowing it to disperse effectively through the car’s internal spaces.
Despite its importance, the fire bottle is extremely light, weighing only a few hundred grams. Teams design the bottle and its mounting points early in the chassis development process so that it integrates seamlessly into the car’s structure. Depending on packaging requirements, the bottle may be located in front of the driver, behind the seat, or in the leg box — the foremost section of the monocoque.
How the System Deploys
The extinguisher is activated by a remote charge of compressed air. When triggered, this charge fills the space between the outer pressure vessel and the inner bladder. As the bladder is compressed, the extinguishant is forced out through a manifold and into a network of tubes routed through the chassis.
These tubes lead to strategically positioned nozzles. Two nozzles are mounted on the rear bulkhead and directed toward the engine compartment, while a third nozzle is located inside the cockpit.
This configuration ensures that the extinguishant reaches the two areas where fire poses the greatest threat: the power unit and the driver’s immediate surroundings.
Redundant Activation Methods
The system can be deployed in two independent ways to ensure reliability in any scenario.
Internal activation is controlled by the driver via a dedicated button on the cockpit switch panel. This button is powered by its own battery, making the system completely independent of the car’s main electrical architecture. Even if the car’s wiring is damaged in a crash, the extinguisher remains fully operational.
External activation is performed by marshals or emergency personnel. A small handle mounted on the right‑hand side of the roll hoop connects mechanically to the car’s main power box and the extinguisher firing mechanism.
Pulling this handle simultaneously cuts the car’s electrics — shutting down the engine — and activates the fire‑suppression system. This redundancy ensures that the extinguisher can be deployed even if the car is rolled, heavily damaged, or electrically compromised.
Designed for Performance and Safety
Although safety systems do not contribute to lap time, they must still be engineered with the same attention to weight, packaging, and reliability as any performance‑critical component.
Teams typically design the extinguisher system in‑house so that the bottle, plumbing, and mounting points match their specific chassis architecture. This approach allows engineers to optimise the shape, weight distribution, and durability of the system from the earliest stages of car design.
The system must also withstand extreme conditions, including vibration, heat, and high‑energy impacts. Its standalone power source and mechanical redundancy reflect Formula One’s broader safety philosophy: no single point of failure should ever prevent a critical safety device from functioning.
A Silent Guardian in the Heart of the Car
The fire‑suppression system is one of the most important but least visible safety features in modern Formula One. By delivering extinguishant directly to the cockpit and engine bay within moments of activation, it provides a vital layer of protection for drivers and helps contain fires before they escalate.
In a sport where performance and safety must coexist, the fire bottle exemplifies the meticulous engineering that underpins every aspect of an F1 car — even the components everyone hopes will never be used.