| Stationary: | Another competitor is following close behind. |
| Waved: | Another competitor is trying to overtake. |
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| Either: | All Clear at the end of a danger area controlled by a yellow flag. Also to signal the start of a formation lap or during the start of a practice |
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| Stationary: | A service car or slow moving car is on the next sector of the track. |
| Waved: | A service car or slow moving car is on the this sector of the track. |
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| Either: | With a white number is a warning to the driver that his behaviour is suspect and he may be black flagged |
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| Stationary: | Danger, slow down sufficiently to ensure full control of the vehicle can be retained. No overtaking. |
| Waved: | Great Danger, slow down considerably, be prepared to take evasive manoeuvres. No overtaking. May be supplemented with yellow lights. |
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| Either: | With a white number is a warning of mechanical failure, driver must stop at the pits |
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| Stationary: | Slipery surface ahead |
| Waved: | Slipery surface imminent |
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| Either: | With a white number, Driver must report to the Clerk of the Course |
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| Either: | Cease racing, proceed to pits with no overtaking, be prepared to stop |
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| Either: | End of race or practice |
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| Either: | Race leader must slow to around 50mph, then act a pace car till green flag shown |
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| Either: | False start (Karting only) |
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