🛡 Field Communications Code Reference

Logistics 4×4 · Edition 1 · 2026 · Chameleon AI Technicians Ltd

A compact code protocol for use when data connectivity is unavailable. Designed for truck drivers, hikers, and emergency services operating across borders or in remote terrain. Three user profiles share a common alert and system vocabulary — enabling cross-agency communication even under severely degraded conditions.

Sharing this reference is encouraged. Interoperability depends on all parties knowing the codes.

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How the codes work

Each code is a letter (category) followed by two digits (severity or sub-type). Within each category, lower numbers mean normal or minor, higher numbers mean serious or critical. The 99 code is always the most severe.

A 1 1
│  └─┴── Severity  11 = nominal → 99 = emergency
└────── Category letter

Multiple codes can be combined in a single message. A free-text note can be appended for additional detail.

D
Driver Truck / cross-border operator
H
Hiker Outdoor / trekking team member
X
Emergency Services SAR / paramedic / ranger / fire
🆘

Universal SOS — works on all profiles

Send these two codes together to trigger an immediate life-threat emergency alert with GPS location to all registered contacts.

A99 H99
⭐
Universal codes — all profiles
A (Alert) and Z (System) are identical across Driver, Hiker, and Emergency Services
A
⚠️
Alert level
CodeMeaning
A11All clear. Situation normal.
A22Minor incident. Self-handling.
A33Caution. Possible problem developing. Monitoring.
A44Assistance needed. Non-urgent.
A55Assistance needed urgently.
A66Serious incident in progress.
A77Critical situation. Multiple problems.
A88Extreme danger.
A99SOS. Life threatening emergency. Send help immediately.
Z
⚙️
System / protocol
CodeMeaning
Z00Heartbeat. No change.
Z01Start of shift / hike / deployment.
Z02End of shift / hike. Safely stood down.
Z03Message acknowledged.
Z04Message corrupted. Please resend.
Z05Relay this message forward.
Z06Relay this message back to base.
Z07Base or command requesting status from all.
Z08Requesting status from this specific contact.
Z09Group or convoy disbanding.
🚛
Driver codes — prefix D
Truck operators, cross-border logistics, convoy drivers
B
🛃
Border
CodeMeaning
B11Approaching border. Within twenty kilometres.
B22In queue at border post. Normal wait.
B33Delayed at border. Paperwork issue.
B44Goods inspection ordered.
B55Unofficial payment demanded.
B66Goods seized by authorities.
B77Vehicle impounded.
B88Driver detained.
B99Refused entry. Turned back.
C
📦
Cargo
CodeMeaning
C11Cargo loaded. All secure. Normal.
C22Partial load or minor shift.
C33Load shifted. Stopping to re-secure.
C44Cargo damaged.
C55Spillage or items fallen from vehicle.
C66Cargo partially stolen.
C77All cargo stolen or seized.
C88Hazmat or cold-chain incident.
C99Total cargo loss.
D
👤
Driver status
CodeMeaning
D11Driver on duty. Driving normally.
D22Driver on a stop. Fuel, meal, or break.
D33Driver loading or unloading cargo.
D44Driver waiting. Customs, checkpoint, or traffic.
D55Driver delayed. Problem. Cannot proceed yet.
D66Driver feeling unwell or fatigued.
D77Driver detained or facing legal issue.
D88Driver breakdown. Cannot continue without help.
D99Driver emergency. Driver in danger.
E
🔧
Vehicle fault
CodeMeaning
E11Engine warning light. Minor. Continuing.
E22Single flat tyre. Changing now.
E33Multiple flat tyres. Cannot change.
E44Engine overheating. Pulled over.
E55Mechanical breakdown. Non-engine.
E66Complete engine failure.
E77Fire.
E88Accident damage. Vehicle cannot move.
E99Vehicle write-off. Total loss.
F
⛽
Fuel
CodeMeaning
F11Fuel tank full.
F22Fuel three-quarter.
F33Fuel half.
F44Fuel quarter.
F55Fuel low. Need refuel within 50 km.
F66Fuel critical. Need refuel now.
F77Running on jerry cans or reserve tank.
F88Fuel contaminated or wrong fuel used.
F99No fuel. Stopped.
G
🚚
Convoy
CodeMeaning
G11Solo vehicle. No convoy.
G22Convoy lead vehicle.
G33Convoy mid position.
G44Convoy tail vehicle.
G55Convoy intact. All trucks present.
G66One vehicle missing from convoy.
G77Multiple vehicles missing.
G88Convoy separated. Regroup at next waypoint.
G99Convoy disbanded.
H
🆘
Help needed
CodeMeaning
H11Need fuel delivered to my location.
H22Need mechanic or mobile workshop.
H33Need medical assistance or ambulance.
H44Need police or official escort.
H55Need recovery truck or crane.
H66Need food, water, or supplies.
H77Need customs agent or documentation help.
H88Need armed escort.
H99Major incident. All assistance needed urgently.
J
🗺
Journey progress
CodeMeaning
J11Journey started. Departed on schedule.
J2225% of route complete.
J33Halfway. 50% complete.
J4475% complete.
J55Approaching destination. Under 10 km.
J66Arrived at destination.
J77Route significantly extended. Major detour.
J88Turned back. Retracing route.
J99Lost. Off route entirely.
K
📡
Communications
CodeMeaning
K11Full communications. All normal.
K22Data only. No voice calls.
K33SMS only. No data or voice.
K44Voice only. No data or SMS.
K55Radio contact only.
K66Satellite communications active.
K77Mesh WiFi only. No cellular.
K88This message relayed via another device.
K99No communications. Sent via third party.
R
🛣
Road conditions
CodeMeaning
R11Good tarmac road.
R22Tarmac with potholes.
R33Gravel or dirt road. Passable.
R44Rough track. Mud or poor surface.
R55Road partially blocked.
R66Road closed or one-lane obstruction.
R77Bridge out or dangerous.
R88Road impassable.
R99No route. Off road or completely lost.
S
🛡
Security
CodeMeaning
S11Situation normal. No threats.
S22General caution in area.
S33Unofficial checkpoint or vehicle following.
S44Criminal roadblock reported ahead.
S55Bribe demanded.
S66Robbery attempt. Repelled.
S77Robbery in progress.
S88Armed attack on convoy.
S99Hijack or kidnap.
T
⏱
Schedule
CodeMeaning
T11On time. On schedule.
T22Slightly delayed. Under one hour.
T33Delayed one to two hours.
T44Delayed two to four hours.
T55Delayed four to eight hours.
T66Delayed one day.
T77Major delay. ETA unknown.
T88Schedule abandoned.
T99Trip aborted. Returning.
V
🚛
Vehicle movement
CodeMeaning
V11Vehicle parked. Stopped safely.
V22Vehicle moving normally.
V33Vehicle moving slowly. Under 20 km/h.
V44Vehicle stuck. Mud, sand, or ditch.
V55Towing another vehicle.
V66Being towed.
V77Vehicle overturned.
V88Accident. Vehicle cannot move.
V99Write-off. Total loss.
W
🌦
Weather
CodeMeaning
W11Clear and dry. Good visibility.
W22Light rain or haze.
W33Heavy rain.
W44Thunderstorm or high wind.
W55Fog or poor visibility.
W66Flood. Road wet but passable.
W77Flood. Road impassable.
W88Dust storm or harmattan. Near zero visibility.
W99Extreme weather conditions. Stopped.
🏕
Hiker codes — prefix H
Trekkers, outdoor teams, wilderness expeditions
H
🆘
Help needed
CodeMeaning
H11Need food or water.
H22Need first aid or medical kit.
H33Need medical assistance or evacuation assessment.
H44Need rescue team.
H55Need helicopter or air evacuation.
H66Need search and rescue.
H77Need shelter or emergency bivouac.
H88Need urgent evacuation. Cannot walk.
H99Major emergency. All assistance needed immediately.
T
🏔
Trail conditions
CodeMeaning
T11Good trail. Well marked. Easy going.
T22Trail intermittent or overgrown.
T33Trail lost. Navigating by GPS or compass.
T44Off trail. Open terrain. Navigable.
T55Steep ascent. Slowing pace.
T66Steep descent. Taking care.
T77Technical terrain. Scramble, rock, or snow.
T88Dangerous section. Crossing carefully.
T99Terrain impassable. Forced to turn back.
U
🎒
Gear / equipment
CodeMeaning
U11All gear in good condition.
U22Minor gear issue. Non-critical.
U33Gear damaged but workaround found.
U44Critical item failing. Tent, stove, or filter.
U55Navigation equipment lost or failed.
U66First aid kit in use.
U77Emergency shelter needed. Setting up bivouac.
U88Multiple critical gear failures.
U99All essential gear lost. Catastrophic.
V
❤️
Vitals / group health
CodeMeaning
V11All group members fit and well.
V22Minor fatigue or discomfort. Continuing.
V33Blisters or minor injury. Slowing slightly.
V44Injury. Significantly slower pace.
V55Member cannot maintain normal pace.
V66Serious injury. Stopped. Assessing evacuation.
V77Member collapsed or unconscious.
V88Medical emergency. Evacuation required.
V99Life threatening. Emergency services needed immediately.
Y
✅
Scheduled check-in
CodeMeaning
Y11Scheduled check-in. All well. On route.
Y22Check-in. Slight delay. Still safe.
Y33Check-in. Significant delay. Still safe.
Y44Off route but safe and navigating.
Y55Missed previous check-in window. Now reporting.
Y66Requesting acknowledgement from base.
Y77Safe arrival at camp or planned waypoint.
Y88Descending. Final leg to trailhead.
Y99Multiple check-ins missed. Emergency alert triggered.
S
🛡
Security
CodeMeaning
S11Situation normal. No threats.
S22General caution. Unfamiliar area.
S33Suspicious activity nearby.
S44Wildlife threat. Keeping distance.
S55Wildlife encounter. Backing away.
S66Aggressive wildlife. Retreating.
S77Hostile people encountered.
S88Threatened or followed. Moving to safety.
S99Immediate danger from people or wildlife.
🚑
Emergency Services codes — prefix X
SAR, paramedics, fire crews, rangers — degraded-comms operations
Aligned with international emergency standards The P (triage) category uses the international P1–P4 priority scale (P1=Immediate, P2=Delayed, P3=Minor, P4=Expectant). The I (incident) and N (count) categories reflect the METHANE major-incident declaration framework used by joint emergency services.
I
🔥
Incident type
CodeMeaning
I11Medical emergency. No scene hazard.
I22Road traffic collision.
I33Search and rescue. Missing person.
I44Fire or structural incident.
I55Flood or water rescue.
I66Hazardous materials or chemical release.
I77Structural collapse.
I88Civil unrest, violence, or armed incident.
I99Major incident declared.
P
🏥
Patient triage
CodeMeaning
P11No casualties on scene.
P22Walking wounded only. P3 — minor.
P33Serious but stable. P2 — delayed.
P44Life-threatening casualties. P1 — immediate.
P55Expectant casualties. P4 — palliative.
P66Mixed triage. Multiple categories present.
P77Mass casualty incident declared.
P88Casualty count incomplete. Scene not cleared.
P99Catastrophic. Multiple fatalities confirmed.
N
👥
Number of casualties
CodeMeaning
N11One casualty.
N22Two to five casualties.
N33Six to ten casualties.
N44Eleven to twenty casualties.
N55Twenty to fifty casualties.
N66Fifty to one hundred casualties.
N77Over one hundred casualties.
N88Unknown number. Scene assessment ongoing.
N99Casualties at multiple locations.
V
💓
Patient vitals
CodeMeaning
V11Conscious and alert. Talking normally.
V22Conscious but confused or agitated.
V33Responding to voice commands only.
V44Responding to pain only. Unconscious.
V55Unresponsive. Breathing present.
V66Not breathing. CPR in progress.
V77Severe haemorrhage. Tourniquet applied.
V88Cardiac arrest.
V99Deceased. Confirmed.
R
🚒
Resources on scene
CodeMeaning
R11First aider only. No professional responder.
R22Paramedic or advanced first aider on scene.
R33Ambulance crew on scene.
R44Fire crew on scene.
R55Police on scene.
R66Multiple emergency services on scene.
R77Incident commander established.
R88Field hospital or casualty clearing station active.
R99All resources overwhelmed. Urgent reinforcement required.
H
📞
Resources required
CodeMeaning
H11No additional resources required.
H22Additional ground ambulance required.
H33Air ambulance or helicopter required.
H44Fire and rescue required.
H55Police or armed response required.
H66HAZMAT or contamination team required.
H77Heavy rescue or urban search team required.
H88Military or specialist support required.
H99Mass casualty response. All resources required.
E
🚁
Evacuation status
CodeMeaning
E11No evacuation required. Treating on scene.
E22Self-evacuation possible. Casualties walking to transport.
E33Vehicle evacuation possible. Road is accessible.
E44Stretcher evacuation required.
E55Air evacuation required. Landing zone needed.
E66Water or boat evacuation required.
E77Technical rescue required. Rope or confined space.
E88Evacuation route compromised. Seeking alternative.
E99Evacuation impossible. Casualties sheltering in place.
S
⚠️
Scene safety
CodeMeaning
S11Scene safe. No hazards.
S22Potential hazards present. Caution advised.
S33Fire, chemical, or structural hazard on scene.
S44Active threat. Scene not yet secure.
S55Hostile persons on scene. Law enforcement required.
S66Contamination hazard. Exclusion zone required.
S77Scene partially cleared. Ongoing risk.
S88Scene unsafe. Responders withdrawn.
S99Immediate danger to responders. Evacuate scene now.

Quick reference — common situations

Same-meaning codes across the three profiles

Situation Driver (D) Hiker (H) Emergency (X)
All clear / normalA11A11A11
Need urgent helpA55 + H44A55 + H44A55 + H33
Life threat — SOSA99 + H99A99 + H99A99 + H99
SMS-only commsK33K33K33
On schedule / en routeT11 / D11Y11J11
Arrived at destinationJ66J66J66
Lost / off routeJ99J99J99
Severe weatherW77–W99W77–W99W77–W99
AcknowledgedZ03Z03Z03
Corrupted messageZ04Z04Z04

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© 2026 Chameleon AI Technicians Ltd · Logistics 4×4 Field Communications Protocol · Edition 1
Sharing this reference is encouraged — interoperability requires it.