Whenever there is a disaster, there are people who get trapped and hurt. That's when search and rescue teams come in and try to find as many people as possible before it has to turn into a recovery exercise. There are a lot of things that search and rescue teams can use to try to find trapped people to save them.
One tool that SAR teams can use is search dogs. These dogs are specifically trained to sniff out people and to alert their handlers that they have found someone. There are different ways that the dog can alert their handler, including sitting down over the spot or standing in a particular way. Barking is not generally one of those ways because the search and rescue site can be very loud and the handler may not hear the dog barking. Once the search turns from rescue to recovery, different dogs may be brought in to search. Those are cadaver dogs, who have been trained to smell out certain smells that are associated with dead bodies.
Another tool that the search and rescue teams can use is a thermal camera. These cameras use infrared in order to find spots that are hotter than other spots. In this case, that means that they would use the camera to search for people who are buried under rubble or under places where people can't see into. The SAR teams will break the disaster site into a grid and then will search systematically using that grid. Doing that will make sure that every single inch of the site will be searched and people found. When the SAR team gets a hit on the thermal camera, they will leave a mark like a flag on that point so that rescuers and first responders can immediately get into the area, assess the area, and then get the person out of the rubble or debris. They will have to do it carefully so that the person isn't injured any further than they may already be and so that the debris isn't destabilized any more than it already is.
One of the biggest priorities when there has been any kind of disaster is to find the living that may be trapped under the rubble and debris. There are several tools that the search and rescue teams can use in order to find those people before something worse happens to them.