Code 8:
Hazardous material present.
Code 9:
The situation is under control – all clear.
Code 10:
Requesting permission to leave the scene.
ETA
Estimated Time of Arrival.
Affirmative
Yes or confirmation.
Backup
Request for additional police units.
Negative
No or disagreement.
All units
Alerting all available officers to a situation.
BOLO
Be on the lookout (used to describe wanted persons or vehicles).
Signal 1:
Officer in trouble – urgent assistance required.