Which of the following codes signifies a request for backup?

The code that signifies a request for backup is 10-12. This code is part of the ten-codes used by law enforcement and emergency services to provide clear and concise communication over radio systems. When an officer calls for 10-12, they are indicating that they need assistance and are requesting other units to respond to their location to provide additional support.

Understanding the context of this code is critical for effective emergency response. Officers frequently find themselves in situations where additional manpower is necessary, whether for safety reasons or to handle a particularly complex incident. Using standardized codes like 10-12 helps ensure that every officer in the field knows exactly what is happening without having to use lengthy explanations.

Other codes listed serve different purposes. For instance, Code 99 typically refers to an officer needing immediate help due to an emergency situation, while 11-15 and 10-54 may refer to specific incidents or statuses that do not pertain to requesting backup. Familiarity with these codes is essential for smooth communication in high-pressure situations.