Rescue in a collapsed building starts before any digging, with a question: who is inside, and exactly where? Teams combine several methods: voice and ear, listening devices, cameras and search dogs. Here is how it works according to the guidelines of INSARAG, the UN-backed International Search and Rescue Advisory Group, and of AFAD, Türkiye’s disaster agency.

The first information comes from people nearby

INSARAG’s field guide says that people on the scene who know the area are the best source of information about who is trapped, and recommends that teams hold quick interviews before moving people away. Who lived in the building, who was in which room, who was out: this decides where the search begins.

Among collapsed buildings, priority goes to sites with confirmed live victims, ranked by whether the rescue is expected to take less or more than 12 hours. Sites where people may be alive but this is not confirmed come after them.

Call out and listen: why teams ask for silence

According to INSARAG, the first step in locating trapped people is a surface line and hail search: rescuers spread out in a line on the surface, call out, then fall silent and wait for an answer. This only works if the site is quiet.

That is why you hear “Silence!” at collapse sites. In INSARAG’s international signalling system, one long three-second blast on an air horn means “cease operations, quiet”; one long and one short means “resume operations”, and three short one-second blasts, repeated, mean “evacuate”. When it sounds, everyone stops and falls silent; only then can a weak voice or a tap be heard.

Listening devices

What teams call “technical search” uses seismic and acoustic listening devices. As a Fire Engineering article explains, sensors placed on hard surfaces of the debris turn the collapsed structure into a large, sensitive microphone. The device can pick up calling, crying, knocking, movement and breathing.

The logic is the same: a team member calls out or knocks, then the operator listens. Depending on the debris, the detection range is about 1.5–7.5 metres for airborne sound and about 15–45 metres for vibrations travelling through the structure. Comparing the signals from several sensors narrows down the person’s location. These devices work best where there is little noise.

Cameras

Once the location is narrowed down, rescuers drill a small hole and push in a flexible pole with a camera at its tip. The camera extends the rescuer’s eye into the void: it shows the person’s condition and a way to reach them. INSARAG notes that teams may also use thermal imaging cameras or drones, depending on the situation.

Search dogs

According to FEMA, search dogs use their exceptional sense of smell to find live human scent even when a person is buried deep in the rubble. Training resembles hide and seek: someone hides with a toy, and when the dog finds them, play is the reward. A review by Jones and colleagues (2004) notes that good search dogs rely on scent rather than sight and do not give up.

Dogs tire too. INSARAG recommends regular rest breaks and, where needed, removing material that masks scent or blocks vision.

Marks on the rubble

In the INSARAG marking system, a large “V” about 50 cm tall is painted on the debris for every located person. “L-2” beneath it means two live victims; “D-1” means one deceased. When someone is removed, the mark is crossed out and updated. They stop the next team from repeating the work; do not erase or write over them.

Teams in Türkiye

According to AFAD’s KAVKAS guide, the Ankara and İstanbul AFAD Search and Rescue units were classified as heavy teams by INSARAG in 2017, and nine other provincial units were accredited as heavy teams in 2018. Teams of other public bodies and civil society organisations are accredited under the national KAVKAS system at light (at least 18 people), medium (at least 38) and heavy (at least 60) level. Heavy teams must have both search dogs and technical search devices.

What this means for you

  • If you are trapped: Use the silence. When you hear someone calling, answer by knocking or blowing a whistle. For more, see trapped under rubble; the emergency whistle and flashlight on your phone can help too.
  • If you are at the site: Be quiet when silence is called, tell teams who lived in the building, and stay off the rubble. INSARAG warns that aftershocks can cause further movement and collapse of structures.

What to do in the first days after an earthquake is collected in the first 72 hours after a major earthquake.