Which code is commonly used to signal emergency traffic, with some agencies using an alternate code?

• A. Code 3 (emergency)
• B. Code 1 (non-emergency)
• C. Code 2 (priority)
• D. Code 4 (all clear)

Answer: (A)

Code 3 signals emergency traffic and requires an immediate, high-priority response with lights and sirens. This designation is widely recognized in patrol operations and dispatch, so units treat it as top urgency and move to the scene as fast as safety allows. Some agencies may use an alternate code for emergency, but the core idea stays the same: the call demands the quickest possible response.

Non-emergency codes indicate routine responses, with no urgency. A priority code conveys urgency but not immediate action, and all clear means the incident is resolved or there is no active threat requiring rapid movement.