How to be Safe During Lightening

Technoparktoday.com:   The Centre for Innovation in Science and Social Action (CISSA), based in Thiruvananthapuram, has called for the immediate need for creating a mass awareness among the public on the phenomenon of lightning and the casualties that occur due to the natural hazard.

The recently-reported lightning incidents in Kerala bring to focus the depth of lack in awareness as well as ignorance about lightning and protection against it.

According to Dr C Suresh Kumar, General Secretary, CISSA, “Lightning is a natural phenomenon and prevention or control of its occurrence is beyond human control. Even though several agencies are working in the state to support affected people against natural calamities, none of the programs of these agencies are effective in reducing the depth of the incident. It is in this context that CISSA believes that lightning needs to be classified as a natural calamity and consider offering financial support to the affected families”.

Dr Suresh Kumar said that Kerala, one of the badly affected states, looks up to the government to take immediate steps to create mass awareness among the public. “Most of casualties could have been avoided if the public been given proper education in lightning protection,” he added.

There is a lack of awareness on the Dos and Don’ts during lightning strikes and this has resulted as a major problem in the effort to alleviate the hazard. CISSA believes that dissemination of information in this regard requires prime consideration, he pointed out.

CISSA has stated that step voltage (touch voltage) has been found as a major reason for the rise in casualties. During a lightning strike (either on a nearby tree or on a building) the current of the lightning reaches ground and it flows to several hundreds of meters through the ground depending upon the strength of lightning current as well as soil conductivity. This current flow creates voltage gradient and can give rise to a high voltage difference between the legs of a person standing or walking on ground. This is called step voltage. A current flow through the body due to step voltage can injure human beings.

Internationally-acclaimed safety rules have been listed down by CISSA to ward off or minimize the harmful effects of lightning. The first and foremost is the 30-30 rule, which says that if the time gap between lightning and its thunder is less than 30 seconds, then one should immediately seek shelter inside a building. Less than 30-second gap means the thunder storm occurred somewhere very nearby and hence it is dangerous to remain outside.

Taking shelter in the inside rooms of buildings is the best way to escape the lightning. Once inside, stay away from any conducting path to the outside. Avoid using electronic appliances, lighting and electric sockets. Telephone use should also be avoided completely, as it has turned out to be the leading cause of indoor lightning injuries. One should not forget to disconnect televisions and radios from the external antennas.

According to experts, staying outside in the open should be avoided during thunderstorms. It is always best to be inside large buildings. But if one finds oneself standing outside, never seek shelter under large trees. This is one of the major causes of lightning casualties. Along with tall trees, elevated locations, mountains and partially enclosed buildings should also be avoided.

In case someone is struck by lightning, appropriate medical attention should be ensured immediately. Deaths can be prevented if the victims are properly attended to. First of all, check the pulse and breathing of the victim. Administer cardio-pulmonary resuscitation (CPR) measures, if necessary. Monitor the victim closely till professional help arrives.

Apart from human injuries and deaths, another matter of concern is the innumerable animals that die due to lightning every year. Equipment damage due to lightning is on the increasing trend.

More and more electronic aids are damaged by surges caused by remote lightning discharges. Suitable Surge Protection Devices (SPDs) installed on power and signal lines can safeguard the electronic equipment from damage and failures. The traditional protective devices like fuse and circuit breakers in electrical distribution of the building do not prevent surges from entering the equipment as their response time is far slower than the fast transient surges.

The external lightning protection installed in buildings properly will protect the structure from a direct lightning strike as well as flow of lightning current over the structure. External lightning protection system will not protect electrical/electronic equipments inside a building during a lightning strike.

Often, such systems may not be effective in Kerala which has a high density of vegetation, particularly coconut trees. Very often, the nearby trees are quite taller than the buildings and lightning strikes the tree and enter the building through ground conduction. In such situations, a simple lightning rod will not give adequate protection and a ring conductor and surge protection devices are need. The public is not aware of this fact, and is being cheated by manufacturers of spurious quality lightning protection equipment, CISSA has pointed out.