What does 10-20 mean?

• A. In service
• B. Location
• C. Signal good
• D. Out of service

Answer: (B)

In radio communication, the 10-code system uses numbers after “10” to convey concise information. The code 10-20 is used to request or report your location. This makes it quick for dispatch to know exactly where a unit is, which is essential for coordinating response, directing resources, and ensuring safety.

So why this is the best fit: it directly communicates “your location,” which is the exact information needed in many field situations. The other options refer to different statuses or conditions that are conveyed by other codes (for example, being in service or out of service, or signaling the radio status). While those states exist in the broader code system, they do not describe location, which is why they don’t fit here. Remember that 10-code meanings can vary by agency, but 10-20 as location is a widely recognized standard.