Emergency Communications
Part of Radio
Emergency communications protocols define how to use radio when life and safety depend on getting a message through reliably and quickly.
Why This Matters
When disaster strikes — flood, fire, civil unrest, medical emergency — normal communication channels fail precisely when they are most needed. Cell networks overload or lose power. Infrastructure goes down. In those moments, radio becomes the lifeline. Communities that have established emergency communication protocols, trained operators, and functional equipment will coordinate responses, direct resources, and save lives. Communities without them will be isolated and overwhelmed.
For a post-collapse civilization, virtually every significant event is an emergency by pre-collapse standards. Fire in a grain store, a disease outbreak, armed raiders, a missing person in winter conditions — all require rapid, reliable communication across distances that cannot be covered on foot in time. Radio emergency communications systems are therefore not a special-case luxury but a core infrastructure function.
The discipline of emergency communications (EmComm) includes much more than the hardware: standardized message formats, priority protocols, authentication procedures, backup frequencies, scheduled check-ins, net management, and training. All of these procedures exist because real emergencies are chaotic, operators are stressed, and information must be passed accurately under conditions that would cause casual operators to fail.
Distress Frequencies and Protocols
Certain frequencies are internationally designated for distress and calling. In a post-collapse environment with diverse equipment, establishing community-wide standards early is critical.
Traditional distress calling frequencies that should remain monitored:
- 500 kHz (CW): traditional maritime SOS frequency (now less used but still recognized)
- 2182 kHz (voice): international maritime distress, monitored by coastal stations worldwide
- 156.8 MHz (FM voice, Channel 16): maritime VHF calling and distress — monitored by any ship with VHF
- 121.5 MHz (voice): aviation emergency frequency, monitored by many aircraft
- 14.300 MHz (USB voice): international maritime mobile service, monitored by amateur stations globally
For a community radio network, designate one primary calling frequency and one backup. The primary is monitored continuously by whoever is on duty; the backup is used if the primary is jammed, occupied, or dead. Document these in writing, post them at all stations, and train everyone who might need to use a radio.
The international distress signal in Morse code is SOS: three dots, three dashes, three dots (… — — — …), sent as a continuous sequence without word spaces. In voice, the distress signal is “MAYDAY MAYDAY MAYDAY” (from French m’aider, help me), followed by identity, position, nature of distress, number of persons, and any other useful information.
A distress message must be sent, received and acknowledged, and then acted upon. An unacknowledged distress call should be repeated at intervals (3–5 minutes) until acknowledged or until the situation prevents further transmission. Log the time of each transmission.
Net Operations
A radio net is a group of stations that communicate on a common frequency at a scheduled time, under the coordination of a net control station (NCS). Nets are the backbone of organized emergency communication.
The NCS initiates the net by calling all stations and taking check-ins. During an emergency net, the NCS:
- Maintains order on the frequency (no two stations transmit simultaneously)
- Prioritizes traffic (distress > urgent > routine)
- Passes messages efficiently (no unnecessary chatter)
- Keeps records of all traffic
- Tracks which stations are in contact and which may have lost communication
Net procedure: when you want to transmit on a controlled net, wait for a pause then say “[Net Control], this is [your callsign], over.” The NCS acknowledges you and either invites you to proceed or puts you in queue. Never transmit over ongoing traffic. If you need to break in with an emergency, say “BREAK BREAK” to alert all stations.
Tactical calls (abbreviated callsigns or position titles like “Base,” “Aid Station,” “Patrol One”) are useful in field operations and emergencies where formal callsign procedures would slow things down. Establish your tactical call system before it is needed.
Message Formats
The value of standardized message formats becomes clear in a real emergency: a stressed, injured, or exhausted operator may still be able to receive a properly formatted message. Unformatted, conversational messages cause errors.
A standard radiogram format includes:
- Number (sequential message number for this station, e.g., NR 47)
- Precedence (ROUTINE, WELFARE, PRIORITY, or EMERGENCY)
- Handling instructions (optional: HOLD UNTIL CONTACT, REPORT DELIVERY, etc.)
- Station of origin
- Check (word count of the text)
- Place of origin
- Time and date filed
- To (addressee)
- Text (the actual message)
- Signature
A message in the field might be: “NR 12 EMERGENCY / FROM BASE / CHECK 9 / 15 MARCH 0800 / TO AID STATION / TEXT: THREE INJURED INCOMING ESTIMATE ONE HOUR NEED SURGERY / SGT MALIK.”
The receiver writes this down and reads it back for verification. The sender confirms accuracy and says “Roger, your copy is correct.” Only when the receiver says “Copy good” is the message confirmed. This procedure eliminates the single biggest source of errors: assuming the other party heard correctly.
Backup Systems and Continuity
The defining feature of emergency communications is that the emergency always happens at the worst possible time. Power fails when it’s most needed. Operators are unavailable. Primary equipment is damaged. A robust emergency communication system anticipates failure and has pre-arranged backups.
Power: all emergency radio stations should have a power source that works without grid electricity. A lead-acid battery charged by solar panels or a hand-cranked generator is the minimum. Document the rated capacity, charge state, and estimated runtime at normal operating power. A 100Ah 12V battery can run a 20W radio (typical HF transceiver at normal power) for roughly 60 hours of receive-only operation or 10–15 hours with moderate transmitting.
Equipment: maintain at least two functional radios per primary operator, one of which is a simple, proven design. A crystal radio always receives; an emergency AM broadcast receiver with batteries covers broadcast reception. A simple CW transmitter (a crystal oscillator, a key, and a power amplifier) can be built quickly from salvaged parts if the primary transceiver is lost.
Training: operators must practice under conditions that simulate emergency stress — tired, under time pressure, with incomplete information. Run regular drills. Simulate equipment failures. Practice message handling until it is instinctive. An operator who has only practiced in calm conditions will make critical errors in a real emergency.
Documentation: all frequencies, schedules, callsigns, procedures, and backup plans must be written down and stored in multiple locations. An emergency communication plan that exists only in one person’s head is not a plan — it is a single point of failure.
Integration with Community Response
Radio communication is a tool, not an end in itself. Emergency communication only has value when it is integrated with community response systems — incident management, search and rescue, medical, logistics. The radio operator’s job is to ensure information flows accurately and quickly to those who need it; the response decisions are made by others.
Establish clear information flows before an emergency: who receives what reports, who issues what orders, who needs to be informed of what events. Map these as a written communications plan. During an incident, the radio net carries only operational traffic — keep personal calls, status checks, and social traffic off the net until the emergency is resolved.
Position a radio operator at every key response location: incident command, aid station, logistics base, field teams. Each operator needs enough training to handle routine traffic without support and enough judgment to escalate anything unusual. Cross-train multiple people for each position — the primary operator will sometimes be unavailable.
The most effective emergency communication systems are built, tested, and maintained before they are needed. A community that waits until disaster strikes to set up its radio net will find that setting up takes just long enough for the situation to become catastrophic. Build the system now, train regularly, maintain equipment in working order, and the system will be there when it is needed most.