Dogs, drones and sound detectors: How rescuers search for quake survivors

Image source, Anadolu via Getty Images Image caption, Rescuers pictured searching through rubble in La Guaira, which has been devastated by last week's earthquakes By Alys Davies Published 6 minutes ago Rescuers are racing to find remaining survivors beneath the rubble of Venezuela's twin earthquakes, in which at least 1,450 people are known to have been killed - with the number expected to rise. The 96-hour window during which survivors were most likely to be found passed on Sunday evening. But on the ground, teams are still hopeful of finding survivors and continue to conduct searches "to the same level of detail as on day one", search and rescue expert Lee Ivory tells the BBC. Ivory is deputy national coordinator for UK International Search and Rescue (UK ISAR) - which is among dozens of foreign rescue teams who are working alongside locals in Venezuela. Armed with equipment ranging from search dogs to sound detection devices and cameras, rescuers are using a range of methods to reach those who are still alive. Search dogs Image source, UK ISAR Image caption, Ivory, whose search and rescuer colleagues have been deployed to Venezuela, says the abilities of search dogs are "amazing" Specially-trained search dogs are used to sniff out where potential victims may be located, says Ivory - who has been deployed to relief efforts following earthquakes in Haiti, Japan and Nepal and is currently helping to coordinate efforts in Venezuela from the UK. They can identify a person's smell even when they are buried as far as 10m (32.8ft) under rubble - and will let out a "really strong and sustained bark" when they do, alerting rescuers to a potential survivor. The dogs are trained using toys imprinted with a human's smell, Ivory explains. Then, when they actually locate a human on the ground, they are handed the toy as a reward by their handler. Search dogs can also be very useful during the technical part of rescue operations, says Sakthy Selvakumaran of the UK-based charity Search and Rescue Assistance in Disasters (SARAID), which deploys personnel to large-scale disasters worldwide. They can find hard-to-navigate paths through rubble to follow a scent or identify different access points to the victim, Selvakumaran tells the BBC. Sound detectors Image source, EPA/Shutterstock Image caption, Sound detection devices are a key technique - as pictured here during the current rescue operation in Venezuela One of the most effective ways of locating victims is "by having a really good listen", Ivory says. Rescuers will shout out into rubble, he says, stating who they are and using some of the local language to see whether they can hear anybody trapped within. Teams also use seismic and acoustic listening devices, which resemble little pots or cans on wires linked up to devices, to try to locate survivors. "In essence, if someone was just scratching on a bit of concrete, we'd be able to pick that up," he says, "even if they are entombed in the building". Cameras