INTRODUCTION:

From the previous article “The Story of Lightning Part 1”, we know that lightning is a natural phenomenon caused by static electricity. We also noted that there are several religious and cultural beliefs associated with lightning and the devastation caused by lightning.

Although the deaths and injuries caused by lightning to animals, cause a lot of pain and suffering to the animals. These animal deaths and injuries, are serious and do often have a large financial impact on their owners. The main aim of these article is to raise “Lightning Safety Awareness” and the effect on human lives.
To be able to get an understanding of the dangers posed by lightning, we need to look at some of the devastation that is caused by lightning.

 

HUMAN DEATHS, INJURIES, AND TRAUMA DUE TO LIGHTNING:
Dr. Ryan Blumenthal, specialist pathologist on lightning deaths, writes “Lightning kills approximately 24 000 people around the world every year. And approximately 240 000 people will be struck or injured but survive a lightning strike, often with severe disabilities. Lightning is a completely random and anonymous killer”.

A Sunday Times newspaper article headline, written in November 2014 was titled “SA in top 5 on the world’s lightning death chart – what scientists are doing to help”. And another article published by R.L. Holle, puts the South African Lightning death rate at an average of 6.3 deaths per million of the population (Blumenthal 2003, 2005) and 8,8 deaths per million in rural areas.

This is a staggering number of deaths each year. International specialists on lightning injuries, agree on a ratio of approximately 10 persons injured to each person killed. Many of these deaths and injuries could have been prevented, if the victims had been aware of the dangers and taken the correct safety precautions. For this reason alone, “Lightning Safety Awareness” is of the utmost importance.

What we also need to take cognisance of the religious and cultural beliefs concerning lightning. Some of these beliefs are, that the Gods use lightning to punish evil people, and lightning is directed by witchcraft, these beliefs on their own often result in additional psychological trauma, not only to the victim/survivor but also to close family members.

As for witchcraft, in some cases an innocent member of the community is accused of being the witch or wizard and they are forced out of the community and possibly in an extreme case they may even be killed. It is often the case that the psychological scars last for a lifetime and have a devastating effect on all involved.

THE BIG KILLERS OF A LIGHTNING STRIKE:

 

Research in the Canada has shown that the biggest cause of lightning deaths is “Ground Current” (40-50%), referred to as “Step Potential” in electrical engineering terms. This is normally current that flows from one foot, through the body, to the other foot. In the picture below the yellow indicated the current flow through the body.

 

Ground Current / Step Potential as per rugrounded.ca

The Second biggest killer is a “Side Flash” (20-30%). This is often cause by standing too close to trees or lightning conductors that are incorrectly earthed. If the electrical wiring, inside a building is sub-standard, a “Side Flash” may even occur within a building.

 

Side Flash as per Protec.com.my

The Second biggest killer is a “Side Flash” (20-30%). This is often cause by standing too close to trees or lightning conductors that are incorrectly earthed. If the electrical wiring, inside a building is sub-standard, a “Side Flash” may even occur within a building.

Contact / Touch Potential as per Protec.com.my

Third on the list (15-25%) is “Contact”, which in electrical engineering terms is “Touch Potential”. This occurs when we are standing on the ground/earth, touching a metal object, which intern is struck by lightning, the lightning current then flows to ground/earth via our arm, through the body and out via the feet. The lightning current could also flow from one arm to the other, if we are touching two different metal objects. In the picture below the yellow indicates the current flow through the body.

Upward Leader as per researchgate.net

Fourth on the list (10-15%) is the “Upward Leader”. This one is more difficult to explained, it is actually the start of a lightning strike, before the actual strike takes place. When the “Upward Leader” and the “Downward Leader” meet, is when an actual lightning strike takes place. Not all “Upward Leaders” meet a “Downward Leader”, however one of the “Upward Leaders” is likely to connect.

This could almost be referred to as an invitation to the lighting to strike a particular object and in this case, it is the person. In the outdoors, we are unable to prevent an “Upward Leader” from occurring from the highest point on our body.

An “Upward Leader” will not be initiated if we are inside a building or a metal enclosed motor vehicle.

Direct Strike as per Protec.com.my

Fifth on the list (3-5%), is the “Direct Strike”. As can be seen from the statistics the “Direct Strike” only accounts for 3-5% of the deaths, this is the one that is most talked about and the other causes are often not taken into consideration.

Building Damage as per Newson6.com.uk

Sixth on the list (possibly between 1-3%), is the “Blunt Trauma”. These deaths are caused by fires, explosions, falling masonry and shrapnel from exploding trees.

From savingadvice.com

HOW WE UNINTENTIONALLY PUT PEOPLE AT RISK:

Every day, around the world, incorrect lightning advise is given that put people at risk. For example, we look at the following case study:

During a thunderstorm in a rural area, a motor vehicle with a family stops outside a house. An adult would probably say to the others in the vehicle “Take the umbrella and run into the house. I will be ok in the vehicle and wait until the thunderstorm stops.”

Now let’s unpack the above case study.

1. The people, while leaving the vehicle are exposed to the “Contact/Touch Potential” which causes 15-25% of lightning deaths. This does happen, the son of a friend was killed while getting into a truck, which at the same time the truck was struck by lightning;

2. Using the umbrella during the thunderstorm, is increasing the risk of both an “Upward Leader” which causes 10-15% of lightning deaths, as well as the risk of a “Direct Strike” which causes 3-5% of lightning deaths;

3. Walking or running to the house, exposes the people to the risk of “Ground Current/Step Potential” which causes 40-50% of lightning deaths;

4. While entering the house, if it is not a lightning safe building, the family could be exposed to the risk of “Blunt Trauma” in the form of falling masonry, if the house was struck by lightning above the door.

5. The only part of the above statements that is correct is the last statement about being safe in the motor vehicle, provide that this vehicle has an enclosed metal roof. It is then a Faraday Cage, the safest environment to be in during a thunderstorm.

An innocent, courteous statement, as shown above can put several people’s lives in danger. When both I and my children were growing up, we were informed at school, that if outdoors during a thunderstorm, we should either look for shelter under a tree or lay flat on the ground. These are very dangerous bits of advice and I wonder how many schools are still teaching the children to take these actions in a thunderstorm.

ACTIONS TO TAKE OUTDOORS DURING A THUNDERSTORM:

If you see the lightning flash and then hear the thunder 30 seconds later, you have just enough time to get into either a close motor vehicle with a metallic roof or into a lightning safe building.

If the time between seeing the lightning flash and hearing the thunder is only 5 second, then you are in extreme danger and you do not have time to get into a lightning safe environment. Avoid trees, stay at least 10m away from any trees, and under no circumstances should you lie flat on the ground. The only possible safe action to take, is to immediately crouch down, with your feet as close together as possible, as indicated in the picture below. It is better to be rained on and become wet, then to expose oneself to the risks of death due to a lightning strike.

The American National Weather Service slogan “When Thunder Roars Go Indoors” remains very good advice. However, it should be noted that not all buildings are lightning safe. In the next article to be written, I will discuss what are lightning safe buildings.