Asia

Nepal earthquake: How does the search and rescue operation work?

  • 27 April 2015
  • From the section Asia

International teams of rescuers and medical experts are arriving in Nepal to help hunt and care for earthquake survivors.

The United Nations, which estimates eight million people live in the 39 districts affected by the earthquake, is helping to co-ordinate rescue efforts.

Many have been left homeless by the disaster and the country is already reported to be running out of water and food. There are also frequent power cuts.

The British organisation, Search and Rescue Assistance in Disasters (SARAID) has sent a team of 14 experts with 1.5 tonnes of specialist equipment. This includes an electrical power generator and power tools for cutting through concrete and steel.

They also have their own tents and food supplies, so they will not be a drain on local resources.

But how exactly does such a large and complex search and rescue operation work? Click on the labels in the interactive below for more.

How a search and rescue operation is carried out

INTERACTIVE
  • How a search and rescue operation is carried out

    ×
  • Strong buildings

    ×

    Rescue workers need to be swift to assess where they are most likely to find survivors inside collapsed buildings. Stairwells or the spaces under large concrete beams can provide what rescue workers call 'voids', in which people may have survived.

  • Video cameras

    ×

    Video cameras placed on the end of flexible poles can be squeezed through gaps in the rubble to help locate survivors. Using this technique means time is saved as less rubble is shifted unnecessarily. Thermal imaging equipment can also be used to locate survivors as their body heat can warm the rubble around them.

  • Listening for survivors

    ×

    Specialist sound equipment can detect the faintest of noises to within a few metres. Silence on the site is needed while a member of the rescue team bangs three times and hopes to hear a response. Carbon dioxide detectors can be used to find survivors rendered unconscious. They work best in confined spaces where they detect the greater CO2 concentration in the air exhaled by those still breathing.

  • Weak buildings

    ×

    Many of the buildings in Nepal collapsed in the initial earthquake or the aftershock. Many older neighbourhoods in the capital, Kathmandu, were made up of poorly-constructed brick buildings and these were largely destroyed in the disaster. Fewer, modern structures collapsed.

  • Local knowledge

    ×

    Local people often know the best locations to begin the search for survivors. After speaking to them rescue workers can quickly select the most promising place to begin their work. Many local people have also joined in the search for survivors.

  • Search and rescue

    ×

    The co-ordinating agency, usually the UN, and the host country, have to take the difficult decision of when to stop looking for a few remaining trapped people and concentrate resources on looking after the thousands of other survivors. The average time for this switch is between five and seven days, but individuals have been known to survive as long as 13 days, if they have access to water.

  • Rescue dogs

    ×

    Dogs are extremely effective at using their sense of smell to pick up on signs of life that human rescuers cannot. They are also able to cover large areas quickly, speeding up the search and rescue process.

  • Lifting equipment

    ×

    Diggers and hydraulic jacks are among the heavy machinery that rescue workers employ to shift rubble. Large concrete slabs on the outside of buildings can be pulled aside by diggers, enabling rescuers to get a view of any people still trapped inside. Rescue workers are also taking chainsaws and other power tools to cut through wreckage.

  • Shifting rubble

    ×

    Before the heavy-lifting equipment arrives, rescuers use pick axes and shovels to dig through the rubble. Other tools used by rescuers include chainsaws, disc-cutters and rebar cutters - which can be used to tackle the metal bars in reinforced concrete.

Strong buildings

Image copyright Getty Images

Rescue workers need to be swift to assess where they are most likely to find survivors inside collapsed buildings. Stairwells or the spaces under large concrete beams can provide what rescue workers call 'voids', or gaps in which people may have survived.

Video cameras

Image copyright PA

Video cameras placed on the end of flexible poles can be squeezed through gaps in the rubble to help locate survivors. Using this technique means time is saved as less rubble is shifted unnecessarily. Thermal imaging equipment can also be used to locate survivors as their body heat can warm the rubble around them.

Listening for survivors

Image copyright Getty Images

Specialist sound equipment can detect the faintest of noises to within a few metres. Silence on the site is needed while a member of the rescue team bangs three times and hopes to hear a response. Carbon dioxide detectors can be used to find survivors rendered unconscious. They work best in confined spaces where they detect the greater CO2 concentration in the air exhaled by those still breathing.

Weak buildings

Image copyright EPA

Many of the buildings in Nepal collapsed in the initial earthquake or the aftershocks. Many older neighbourhoods in the capital, Kathmandu, were made up of poorly-constructed brick buildings and these were largely destroyed in the disaster. Fewer modern structures collapsed.

Local knowledge

Image copyright Getty Images

Local people often know the best locations to begin the search for survivors. After speaking to them rescue workers can quickly select the most promising place to begin their work. Many local people have also joined in the search for survivors.

Search and rescue

Image copyright Reuters

The co-ordinating agency, usually the UN, and the host country, have to take the difficult decision of when to stop looking for a few remaining trapped people and concentrate resources on looking after the thousands of other survivors. The average time for this switch is between five and seven days, but trapped individuals have been known to survive as long as 13 days, if they have access to water.

Rescue dogs

Image copyright Getty Images

Dogs are extremely effective at using their sense of smell to pick up on signs of life that human rescuers cannot. They are also able to cover large areas quickly, speeding up the search and rescue process.

Lifting equipment

Image copyright AFP

Diggers and hydraulic jacks are among the heavy machinery that rescue workers employ to shift rubble. Large concrete slabs on the outside of buildings can be pulled aside by diggers, enabling rescuers to get a view of any people still trapped inside. Rescue workers are also taking chainsaws and other power tools to cut through wreckage.

Shifting rubble

Image copyright Reuters

Before the heavy-lifting equipment arrives, rescuers use pick axes and shovels to dig through the rubble. Other tools used by rescuers include chainsaws, disc-cutters and rebar cutters - which can be used to tackle the metal bars in reinforced concrete.

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