Signaling, communication, and rescue coordination

Send useful information, conserve communication tools, and make yourself easier to locate safely.

General field reference, not medical advice. Use it to support immediate decisions, then follow 911, rescue coordinators, medical professionals, current warnings, and local agency guidance.

Act now

1. Call 911 or activate SOS when there is a life-threatening emergency.

2. Send coordinates, the coordinate format, the problem, and the number of people.

3. State weather, terrain, visibility, and access obstacles.

4. Follow dispatcher or rescue-coordination instructions.

5. Keep the device on and monitored unless battery conservation instructions require scheduled check-ins.

Choose the best available communication path

Cell calls can carry more information than text when service is stable. Text may succeed with a weaker or intermittent connection. Satellite messengers and personal locator beacons can reach beyond cell service, but they need correct setup, a view of the sky, and practice before the emergency.

Do not assume an SOS button immediately produces a helicopter. Rescue method and timing depend on location, weather, daylight, aircraft availability, patient condition, and responder safety.

Send a useful first message

A concise message should answer:

• Where: latitude and longitude, coordinate format, elevation if known, and nearby landmarks;

• What: injury, illness, lost person, fire, vehicle problem, or other threat;

• Who: number of people, ages if relevant, and patient condition;

• When: time of incident and meaningful changes;

• Conditions: weather, visibility, terrain, hazards, and shelter;

• Resources: first aid, warmth, water, lights, battery, and ability to move.

Update rescue coordinators when the location or patient condition changes. Avoid repeated nonessential messages that consume battery or create conflicting information.

Signal visibly and audibly

Use high contrast and repetition. Three whistle blasts, repeated after a pause, are widely recognized as a distress pattern. At night, use repeated light signals. In daylight, bright fabric or a reflective surface can help when used without directing intense light at aircraft.

Select a signal site that is visible but safe. Do not stand on an exposed ridge during lightning, enter swift water, or create an uncontrolled fire to become more visible.

Prepare for responders

Secure loose objects before aircraft approach. Keep people and animals controlled. Never approach a helicopter until directed by the crew. Point out wires, dead trees, steep slopes, and other hazards. Follow instructions even when they differ from the group’s original extraction idea.

If the group must leave the reported location because of immediate danger, send the change when possible and leave a clear record of direction, time, and destination.