Ten-code

Ten-codes, properly known as ten signals, are code words used to represent common phrases in voice communication, particularly in radio transmissions. The codes, developed in 1937 and expanded in 1974 by the Association of Public Safety Communication Officials (APCO), allow for brevity and standardization of message traffic. They are widely used by law enforcement officers in North America.

Some organizations and municipalities also use other codes in addition to the ten-codes. An example is the California Highway Patrol's use of eleven-codes.

Historic overview

Ten-codes were adapted for use by CB radio enthusiasts before its pop culture explosion in the late 1970s, thus many of the phrases, such as 10-4 and "what's your twenty" have entered everyday use in the English language. A popular fictional account of ten-codes in use among CB-communicating truckers may be heard in the 1978 movie Convoy.

In the fall of 2005, responding to inter-organisational communication problems during the rescue operations after Hurricane Katrina, The United States Federal Emergency Management Agency (FEMA) discouraged the use of ten-codes and other codes due to their high variability in meaning (see the November 2005 articles in External links, below).

List of 10-codes

The following list, given in ascending order and grouped by decade, illustrates the current usage of various 10-codes (note the disclaimer immediately above the list). Only a handful of them are standardized. Some are fairly consistent, while others (such as 10-40) can have completely different meanings, many of which are not listed here.

Presentation:

• Multiple meanings for the same code are in a bulleted list
• The first bold definition is the current APCO specification, a standard that has been adapted by most law enforcement agencies.
• Popular alternate meanings follow in bold.
• Less common meanings are in regular typeface
• Meanings specific to CB radio are set in italics.

Disclaimer: The list is intended to show the most common codes and help provide an estimate of what a code's definition is. A search for local ten-code tables should be performed first before using the list.

10-0s

Code	Meaning(s)
10-0	use caution
10-1	poor reception
10-2	good reception
10-3	stop transmitting change channels
10-4	message received, affirmative, ok, understood
10-5	relay this information to ___
10-6	busy
10-7	out of service
10-8	in service
10-9	please repeat your message

10-10s

Code	Meaning(s)
10-10	out of service, offduty negative transmission completed welfare check
10-11	animal problem road-side check talking too fast en route
10-12	standby visitors present disregard call in reports at scene check revocation
10-13	advise weather/road conditions, civilians present and listening call-in resume
10-14	suspicious person or prowler convoy or escort
10-15	civil disturbance prisoner/suspect in custody
10-16	domestic disturbance make pickup at ___
10-17	meet complainant pick up papers at ___ urgent business
10-18	urgent complete assignment ASAP anything for us? drunk
10-19	return to station

10-20s

Code	Meaning(s)
10-20	specify location/my location is ___
10-21	please telephone ___
10-22	disregard report to ___ send blood technician
10-23	arrived at location/on scene stand by on this frequency status check en route to call sex offense
10-24	assignment completed trouble at station unit not available direct traffic
10-25	report to ___ please contact ___ do you have contact with person come in for traffic officer needs help
10-26	detaining suspect (implying "please expedite") check auto registration ETA ___ disregard last info phone residence
10-27	drivers license request vehicle registration request I am moving to channel ___ any answer
10-28	vehicle registration request driver's license request identify your station missing person
10-29	arrests/warrants request time is up for contact

10-30s

Code	Meaning(s)
10-30	unauthorized use of radio danger/caution special check at ___ juvenile
10-31	crime in progress domestic disturbance check for local warrants suspicious person
10-32	person with gun fight in progress radio check check NCIC DWI test
10-33	emergency, all units stand by officer needs help disturbance at ___ fire
10-34	riot frequency open (cancels 10-33) help needed trouble at jail correct time meet officer
10-35	major crime alert confidential information suspicious person
10-36	correct time of day?
10-37	suspicious vehicle identify yourself wrecker needed at ___ shoplifter time of day?
10-38	stopping suspicious vehicle ambulance needed station report satisfactory phone communications vandalism
10-39	run with lights & siren your message was delivered false alarm, premises were occupied contact officer disturbance

10-40s

Code	Meaning(s)
10-40	run silent (no lights & siren) false alarm, no activity, premises appears secure please tune to channel ___ expedite advise if available suspicious person dead animal mental patient lunch
10-41	begin duty radio test intoxicated person debris in street neighbor trouble
10-42	end duty traffic accident at ___ malicious mischief request dispatch times
10-43	information traffic jam at ___ request criminal history pick up passenger armed robbery rescue call
10-44	permission to leave patrol I have a message for you transmission received rape traffic accident (no injury)
10-45	animal carcass pick up officer fueling vehicle all units in range please report coffee break traffic accident (injury) non-injury accident (Kentucky)
10-46	motorist assist lunch break fuel break wrecker injury accident (Kentucky)
10-47	emergency road repair call home missing person drunk driver blood run license plate check (Kentucky)
10-48	traffic control request criminal history runaway juvenile use caution
10-49	traffic light out en route to assignment bathroom break any traffic serving warrant

10-50s

Code	Meaning(s)
10-50	accident no messages break channel auto accident with property damage
10-51	wrecker needed auto accident with injuries phone message
10-52	ambulance needed fatal auto accident message for assignment alarm
10-53	road blocked silent alarm
10-54	animals on highway silent pursuit car stop
10-55	intoxicated driver or DWI security check ambulance call
10-56	intoxicated pedestrian warrant indicated arrived at scene
10-57	hit & run accident narcotics officer at pistol range
10-58	direct traffic wrecker DOA teleprinter message
10-59	escort or convoy out of car checking violation ambulance bomb threat

10-60s

Code	Meaning(s)
10-60	squad in vicinity traffic stop what is next message number? coffee break assist motorist
10-61	personnel in vicinity stand by for CW traffic clear of traffic stop weather conditions? lunch break
10-62	reply to message unable to copy, use phone check for rising water logged on/off
10-63	prepare to copy make written copy net directed to ___ need barricades
10-64	local message message for delivery net clear, resume normal traffic field investigator
10-65	net message assignment kidnapping
10-66	net message cancellation bathroom break
10-67	clear for next message prepare to copy person calling for help all units comply
10-68	dispatch message repeat dispatch switch channels
10-69	message received any calls holding for me? sniper

10-70s

Code	Meaning(s)
10-70	fire alarm fire fire followup prowler net message chemical spill
10-74	negative
10-76	enroute to location fresh coffee
10-78	need assistance major accident with injury request wrecker
10-79	notify coroner bomb threat hit & run

10-80s

Code	Meaning(s)
10-80	pursuit in progress bomb has exploded tower lights out on assignment demonstration
10-81	breathalyzer request stop for interrogation reserve hotel room officer ___ will be at your station at vehicle maintenance civil disturbance/riot
10-82	reserve lodging stop for interrogation/arrest traffic signal out cover assistance
10-83	work/school crossing detail call station units stop transmitting at radio shop officer in trouble
10-84	advise ETA checking officer status my telephone number is ___ follow-up broken utility main
10-85	arrival delay due to ___ prepare to copy info my address is ___ loose livestock
10-86	officer on-duty utility line down
10-87	pickup or prisoner transfer pickup payroll check dead body
10-88	advise telephone station call special assignment true alarm
10-89	bomb threat send radio repair officer at academy

10-90s

Code	Meaning(s)
10-90	bank alarm radio repair to be at station officer at headquarters false alarm
10-91	pick up prisoner/suspect talk closer to the mike prepare your inspection vehicle fuel bank holdup alarm
10-92	parking violation your signal is weak officer at court
10-93	blockage please check my frequency
10-94	street racing give me a long count
10-95	prisoner/suspect in custody transmit dead carrier for 5 seconds
10-96	mental patient detain prisoner/suspect
10-97	test signal arrived at scene possible wanted person in vehicle known offender officer at court
10-98	prison/jail break criminal history indicated officer at juvenile court assignment complete
10-99	warrants/stolen indicated officer needs assistance/held hostage mission complete bathroom break

10-100s and up

Code	Meaning(s)
10-100	bathroom break dead body
10-200	police needed

See also

• Eleven-code
• Q code
• Voice procedure
• Z code

External links

• The End of the Ten-Code? – By Tim Dees, Officer.com, 9 November 2005
• 10-4 no more? – By Megan Scott, asap (AP), 25 November 2005
• [1] – The APCO Bulletin, January 1940. The first official publication showing the 10-codes (on page 8).