By Dr Ajay Paul
Some recent tremors around Delhi have triggered discussions on earthquakes, particularly the consequences of their occurrence in densely populated urban areas. Unfortunately, it has also given rise to some rumours and fear mongering. So, let’s first be clear on a few things.
Earthquakes cannot be predicted. Not yet. Also, they cannot be prevented. They will happen. There is no particular time when the probability of an earthquake happening is higher, or lower. In fact, in areas classified as seismic risk zone IV and V, there is always a probability of a big earthquake of magnitude 6 and above. The Delhi region and the entire Himalayas are in this risk zone. But tremors, even a series of them in a short period of time, are not a forewarning of any upcoming big event. There is ongoing research across the world on identifying precursors to an earthquake, but as of now there is no change in the situation.
But, as has been pointed out in this newspaper a few days ago, even if we did have the capability to predict earthquakes, it would be futile if we are not adequately prepared for it. It is not possible to evacuate entire cities and move the populations to a safer place to save lives.
The key to saving lives and minimising the damage from earthquakes lies not in prediction but in preparation. We need to strengthen our existing buildings and structures, and integrate safer designs in new and upcoming ones. As citizens, we need to know exactly what to do if an earthquake happens. Countries like Japan, which experience frequent earthquakes, have shown that following some relatively simple practices can ensure very little disruption even when strong earthquakes occur.
While some elements of earthquake preparedness like building safety or regular mock drills, require initiative from the government authorities and local administration, there are several things that the citizens can do on their own to keep themselves prepared and safe.
Here are some of the things that we routinely emphasise on while interacting with school children and residents in areas that are very prone to earthquakes. Not all of this may be relevant to people in all locations and in all situations, but being aware of the standard safety measures is helpful. Most of these pointers are known to many people, but it needs to be reiterated, and implemented.
Before an earthquake: We must ensure regular earthquake mock drills annually at all places, irrespective of the earthquake zone the region falls in. All new buildings must incorporate earthquake-resistant designs and older buildings need to be retrofitted. Emergency supply kits must be kept ready. It can include readymade food like biscuit packets, water bottles, and medication and first aid supplies. It should also have a flashlight, essential clothing and toiletries. This kit must be regularly updated as the need arises. Further, within housing societies, we must identify common places to assemble, and take shelter.
During an earthquake: Remain calm. Ground shaking does not last more than a minute. If one is inside a building, then duck, cover, and hold. Place yourself under some sturdy furniture, and cover as much of your head and upper body as you can. Hold on to the furniture. If you can’t get under a sturdy furniture, move to an inside wall or archway, and sit with your back against the wall, bring your knees to the chest, and cover your head. Do not try to come out of the building once the shaking has started. If outdoors, then rush to an open area, away from all structures, especially buildings, bridges and overhead power lines. If you are driving, stop at the earliest — preferably in an open area — and away from structures, especially bridges, overpasses, tunnels, and overhead power lines. Stay as low inside the vehicle as possible.
If you get trapped in debris, then do not light any matchbox or lighter. Do not shake your body until necessary, and do not remove dust till necessary. It can create problems for breathing. If possible, cover your face with a handkerchief or cloth. Crucially, hit something on a pipe or wall, so that the rescuers get to know and find you; but do not shout too much because it will tire you out. Besides, dust and gases can go inside your body.
After the earthquake: Remain calm. Move cautiously and check for unstable objects and other hazards above and around you. Check your body for injuries, and help those around you and provide first aid. Inspect gas, water and electric lines. If there are leaks, or if there is any doubt over leaks, shut off the main supply. Evacuate immediately if you hear or smell gas, and cannot shut it off. Report leaks to the authorities, and stay away from damaged buildings. Tune in to radio/TV for emergency information, and additional safety instructions.
Finally, there are some general practices, too, that are important: Keep enough stocks in your home to meet your needs for at least seven days. Assemble a disaster supply kit with items that you may need in case of an evacuation. Store these stocks in sturdy but easy-to-carry containers. Do not keep any heavy material above door height, and do not sleep with your head below an electric bulb/light/lamp.
Dr Paul is an earthquake scientist at the Wadia Institute of Himalayan Geology, Dehradun.