By Jessica Pope
Have you ever overheard a conversation between a law enforcement officer and dispatch personnel? If you answered yes, have you ever wondered what they were discussing with a 10-this and a 10-that?
Ten-codes were developed in the 1940s, at a time when police radio channels were limited, to reduce use of speech on the radio, according to experts at Officer.com. Some believe it originated with a man named Charles Hopper, a communications director with the Illinois State Police who was involved in radio for many years and saw a need to abbreviate radio transmissions on state police bands.
Often used by law enforcement personnel, as well as other groups, the ten-codes represent everyday phrases in voice communication. The codes, which were expanded by the Association of Public-Safety Communications Officials during 1974, allow for brevity and standardization of message traffic.
• 10-0 —Caution
• 10-1 —Unable to copy, change location
• 10-2 — Signal good
• 10-3 — Stop transmitting
• 10-4 — Acknowledgment (OK)
• 10-5 — Relay
• 10-6 —Busy, stand by unless urgent
• 10-7 —Out of service
• 10-8 — In service
• 10-9 — Repeat
• 10-10 — Fight in progress
• 10-11 — Dog case
• 10-12 — Stand by (stop)
• 10-13 — Weather or road report
• 10-14 — Prowler report
• 10-15 — Civil disturbance
• 10-16 — Domestic disturbance
• 10-17 — Meet complainant
• 10-18 — Quickly
• 10-19 — Return to ...
• 10-20 — Location
• 10-21 — Call ... by telephone
• 10-22 — Disregard
• 10-23 — Arrived at scene
• 10-24 — Assignment completed
• 10-25 — Report in person (meet)
• 10-26 —Detaining subject, expedite
• 10-27 — Driver’s license information
• 10-28 — Vehicle registration information
• 10-29 — Check for wanted
• 10-30 — Unnecessary use of radio
• 10-31 — Crime in progress
• 10-32 — Man with gun
• 10-33 — Emergency
• 10-34 — Riot
• 10-35 — Major crime alert
• 10-36 — Correct time
• 10-37 — (Investigate) suspicious vehicle
• 10-38 — Stopping suspicious vehicle
• 10-39 — Urgent, use light and siren
• 10-40 — Silent run, no light or siren
• 10-41 — Beginning tour of duty
• 10-42 — Ending tour of duty
• 10-43 — Information
• 10-44 — Permission to leave ... for ...
• 10-45 — Animal carcass at ...
• 10-46 — Assist motorist
• 10-47 — Emergency road repair at ...
• 10-48 — Traffic standard repair at ...
• 10-49 — Traffic light out at ...
• 10-50 — Accident (fatal, personal injury, property damage)
• 10-51 — Wrecker needed
• 10-52 — Ambulance needed
• 10-53 — Road blocked at ...
• 10-54 — Livestock on highway
• 10-55 — Suspected DUI
• 10-56 — Intoxicated pedestrian
• 10-57 — Hit and run (fatal, personal injury, property damage)
• 10-58 — Direct traffic
• 10-59 — Convoy or escort
• 10-60 — Squad in vicinity
• 10-61 — Isolate self for message
• 10-62 — Reply to message
• 10-63 — Prepare to make written copy
• 10-64 — Message for local delivery
• 10-65 — Net message assignment
• 10-66 — Message cancellation
• 10-67 — Clear for net message
• 10-68 — Dispatch information
• 10-69 — Message received
• 10-70 — Fire
• 10-71 — Advise nature of fire
• 10-72 — Report progress on fire
• 10-73 — Smoke report
• 10-74 — Negative
• 10-75 — In contact with ...
• 10-76 — En route ...
• 10-77 — ETA
• 10-78 — Need assistance
• 10-79 — Notify coroner
• 10-80 — Chase in progress
• 10-81 — Breathalyzer
• 10-82 — Reserve lodging
• 10-83 — Work school crossing at ...
• 10-84 — If meeting ... advise ETA
• 10-85 — Delayed due to ...
• 10-86 — Officer/operator on duty
• 10-87 — Pickup or distribute checks
• 10-88 — Present telephone number of ...
• 10-89 — Bomb threat
• 10-90 — Bank alarm at ...
• 10-91 — Pickup prisoner or subject
• 10-92 — Improperly parked vehicle
• 10-93 — Blockade
• 10-94 — Drag racing
• 10-95 — Prisoner or subject in custody
• 10-96 — Mental subject
• 10-97 — Check signal
• 10-98 — Prison or jail break
• 10-99 — Wanted or stolen indicated
Note: While ten-codes were intended to be a terse and concise and standardized system, a great deal of diversity between departments and jurisdictions in terms of meanings has been reported. All codes listed above are from the Official Ten-Code List of the Association of Public-Safety Communications Officers.
