In the event of a racing incident, the stewards will send out the safety car to neutralise the race, providing a safer environment for the marshals who need access to the track to clear it.
For a minor incident, the stewards can deploy the Virtual Safety Car which is communicated to the driver by a series of lights on the side of the track. The driver must reduce speed to the required delta, usually around 30% slower than under race conditions.
Once the incident is cleared the VSC light is extinguished and racing resumes. The VSC has the benefit of being able to switch on and off without the field having to complete the lap as it would under a full safety car.
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