When lightning strikes

Australia is subject to some of the most volatile weather conditions in the world and has experienced some of the hottest days and months on record over the past year.

According to the Bureau of Meteorology (BOM), 2016 continued the trend of high temperatures in Australia by becoming the country’s fourth hottest year on record.

At the same time, however, 2016 also recorded above average rainfall measurements for most of the country, reaching 17 per cent more than usual.

Associated with rainfall is storms, and with storms comes lightning, which serves as a threat to mine sites. Back in 2012, two FIFO workers were affected by lightning strikes near Port Hedland in Western Australia, while working on Fortescue’s Solomon rail mine.

One of the workers, a 24-year-old, was directly struck and suffered burns to five per cent of his body; the other suffered minor neck injuries after he was knocked to the ground.

“There have been many fatalities in the last 12 months related to lightning,” Burstall told Australian Mining. “In fact some statistics in the United States say that lightning kills more people than what sharks do.

“It happens anywhere where you’ve got the basis of electricity. Lightning – bulk lightning – is a positive energy pulse which is a very high average voltage, and it will reach an area of the ground which is also moist, where there’s water mixed with minerals.”

Each day, there are around 100 lightning strikes per second. The United States National Oceanic and Atmospheric Administration notes that lightning can heat up to nearly 28,000 degrees Celsius, with some reports claiming that temperature is up to five times hotter than the sun’s surface.

During Queensland’s summer storms in December last year, the state’s south east coast recorded more than one million lighting strikes, according to Energex. Some of these struck homes, caused injuries and even killed backpacker at the top of Mount Warning.

To help reduce the likelihood of being struck by lightning, TESA Electronics has released two lightning detection devices – the StrikeAlert LD1000 and StrikeAlert HD LD3000. TESA Electronics director Robert Burstall said the LD1000 was designed for more general recreational purposes. It has a 180-degree scanning range and users must face the direction of where the lightning is coming from.

TESA Electronics StrikeAlertHD lightning detection system

The LD3000, however, is for industrial use and has a 360-degree scanner.

“This particular model is targeted obviously for industry where there’s a lot of conductivity that is where lightning will strike the ground, such as open cut mines, large vehicles working, and also based on water content in the surrounding areas,” Burstall said.

He explained that lightning strikes were more likely in the mining industry, particularly on sites that deal with metals – both metals that are used and the metals mined – that involve sluicing and where the ground is damp.

“[This] is very attractive to the lightning seeking a negative area to dispense its energy,” he said, adding that it would alert the user of any disturbance, either cyclonic or otherwise.

Both devices are roughly the same size as a smartphone and are battery powered, lasting roughly 10-15 hours from when they are triggered.

The LD3000 has an intuitive graphical display, allowing operators to visually see the lightning strike distance and the one-hour storm trend; it tracks lightning in all directions and has the option of either an audible or vibrate warning either before (and during) lightning is in striking distance.

The device also has LED indicators that light up accordingly at distances of 38-64km, 20-38km, 10-20km and within 10km. There is also the option of selecting the unit to shut off after two hours if no lightning has been detected. Burstall said it gained a lot of interest in the mining industry.

“I know there has been considerable interest in the mineral mining fields – gold and otherwise – pretty much all the minerals for this type of alert device,” he said.

While lightning cannot be prevented, Burstall emphasised the importance of using the device to protect workers on site.

“It’s a safety precaution – a top level safety precaution – against any fatality or damage that can occur personally and otherwise wherever the person may be,” he explained.

“There are also horrendous soundwaves that are created and pressure waves that are created by these strikes that can damage humans.”

Burstall added that it was also useful in the emergency services as lightning also causes fires.

“That’s one of the main problems in Australia outside the mining area,” he said. “We have sold a considerable amount of these devices to different fire safety brigade areas.”

In addition, Burstall identified several steps operators can take to minimise the chance of getting struck such as avoiding high-ground, water, solitary trees, open spaces and metallic objects. And if they are in a large vehicle to ensure they close their windows and are sitting in a non-metal seat.

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