Lightning strikes can cause severe injuries in a flash

SINGAPORE — It has been 30 years since businessman Chew Lip Heng, 51, survived a lightning strike but a feeling of dread and fear whenever a thunderstorm rolls around has not gone away.

Mr Chew was doing his National Service at the time, and was heading back to camp in Jurong with his friend on a stormy night. As they passed an area with antennas, a bolt of lightning struck a fence nearby.

It rebounded, hitting Mr Chew’s umbrella. He felt sharp searing pain in his right arm — which was holding the umbrella — before falling to the ground. He miraculously escaped uninjured and the terrified pair then ran for shelter.

Likening the sensation to “being electrocuted”, Mr Chew said he developed a great fear of lightning after the incident.

“We are taught that lightning is supposed to hit the highest point but this wasn’t the case for myself. Knowing that makes me even more fearful (of lightning),” he said.

“In my case, a side flash probably occurred. I remember that my skin was moist at the time due to the rain and my umbrella probably contributed to the lightning strike. The current was strong enough to be felt but, thankfully, weak enough to spare me any injuries.”

A side flash, which reportedly accounts for about a-third of all lightning injuries, refers to lightning that jumps from an object or a person to another person, according to the United States’ National Oceanic and Atmospheric Administration (NOAA). People who were indoors, but who were using wiring or near enough a structure that had been struck, have reportedly also been injured.

NOVEMBER ONE OF THE PEAK THUNDERSTORM MONTHS

Lightning was thought to have hit an SMRT train near Bedok on Monday (Nov 20) and its driver was admitted to the hospital, but checks later revealed that lightning had struck trackside equipment and not the train. Rail operator SMRT also explained how its trains are protected by an enclosure called a “Faraday cage”, consisting of conductive material that blocks electric fields and currents.

Thunderstorms produce lightning. Singapore has one of the highest occurrences of lightning activity in the world, with an average of 168 thunderstorm days per year, according to the National Environment Agency’s (NEA) website.

November is one of the peak thunderstorm months here.

In Singapore, lightning strikes are traditionally more common in the monsoon months between April and May, and October and November, said Dr Lim Er Luen, consultant at the emergency medicine department of National University Hospital (NUH).

From 2012 to this year, the hospital has seen 16 cases of lightning strikes. Victims tend to be younger adults and males, as they are more likely to be in open areas when lightning strikes occur, said Dr Lim.

Besides a side flash, lightning may enter a person through several ways such as in a direct strike, via ground current or contact injury (where the lightning strikes an object the victim is holding), said Dr Jeremy Wee, senior consultant at the department of emergency medicine and director of trauma services at the Singapore General Hospital.

A blast injury, which occurs when a blast effect is produced together with thunder and causes the person to fall, may also cause traumatic injuries.

Ground currents — when lightning strikes the ground near the victim and spreads out as a potentially deadly current through the ground — account for half of lightning deaths and injuries, according to the NOAA.

Associate Professor Michael Li of Nanyang Technological University, whose research interests include transportation science, said it is “very rare” for passengers and drivers of vehicles to be struck by lightning due to safety features in place.

“For example, the areas that are touched by passengers or the driver, like handles, are usually rubberised. But if the vehicle is getting old and there’s wear and tear, it is possible for the insulation system to be compromised,” said Assoc Prof Li.

According to the NEA, a common misconception is that lightning occurs only when there is rain; it can, in fact, strike a distance away from the thunderstorm cloud where there is no rain or even when skies appear to be clear. These “bolts from the blue” have been documented to strike even as far as 16 km from the thunderstorm cloud.

DEATH BY LIGHTNING

Approximately 10 to 30 per cent of people who sustain lightning strikes die from them, said the experts. Two-thirds of deaths related to lightning strikes occur during the first hour, usually due to a fatal abnormal cardiac rhythm, cardiac arrest or respiratory failure, said Dr Wee.

The most common cause of death from a lightning strike is when the electrical charge courses through the heart, disrupting the heart’s intrinsic electrical system, said Dr Lim.

“This causes the heart to stop beating. Alternatively, the electrical charge may also disrupt breathing centres in the brain, causing the victim to stop breathing,” he said.

In such cases, the person’s survival chances may be improved if cardiopulmonary resuscitation (CPR) is performed early and there is access to an automated external defibrillator, said the experts. This should be followed by prompt evacuation to the hospital.

HOTTER THAN THE SUN’S SURFACE

For victims who survive, more than seven in 10 may have long-term disabilities, said Dr Wee.

“Those who survive the first hour (of being struck by lightning) tend to have injuries such as thermal burns, kidney failure or injuries to the muscle, eye or nerves,” he said.

Lightning can heat the air it passes through to temperatures of over 27,000 degrees Celsius, which is hotter than the surface of the sun, according to NOAA.

Body tissues may be damaged as a result of the huge energy transmitted by the current but this is not common, said NUH’s Dr Lim.

“In such situations, there may be burn marks on the skin and hair, and the clothes may be burnt and torn, giving the mistaken appearance that the victim was assaulted rather than struck by lightning. There are also reports of survivors who suffer from memory loss, speech problems and other brain and nerve injuries,” said Dr Lim.

Treatment for victims varies, depending on the type and extent of their burns and injuries. Severe cases are likely to require intensive care with circulatory and ventilator support, said Dr Wee.

For survivors, the trauma of surviving a lightning strike may go beyond physical health.

About 30 per cent of survivors experience post-traumatic stress disorder, said Dr Wee. Depression is another common aftereffect.

Other common complaints of survivors include fatigue, lack of energy, poor concentration and emotional lability, said Dr Wee. The latter refers to rapid and exaggerated changes in mood, where strong emotions such as uncontrollable laughing or crying, or heightened irritability occur.

Having survived a lightning strike, Mr Chew said the incident piqued his interest in the topic.

“I later learnt that many variables, even wind velocity, can affect where lightning strikes. The best protection is to remain indoors when there’s lightning activity,” he said.

For lightning protection tips, visit www.nea.gov.sg/training-knowledge/weather-climate/lightning-thunderstorms.