Summer is the peak time for thunderstorms, and when lightning strikes, it can do so with incredible force. The National Severe Storms Laboratory of the National Oceanic and Atmospheric Administration notes that a bolt of lightning can have anywhere from 100 million to 1 billion volts, and it can heat the air to anywhere from 18,000 to 60,000 degrees Fahrenheit.
One key element to lightning safety is monitoring the danger of storms to help protect employees working outdoors, so it is important to understand the outlooks predicted by the National Weather Service. Workers and employers should be aware of weather forecasts, and employers should train their workers on severe weather plans, and keep emergency supplies, including a battery-operated weather radio, available.
The National Weather Service Storm Prediction Center uses this terminology to communicate the outlook of severe weather:
- Category 1, marginal risk, indicates isolated severe thunderstorms are possible. This outlook is common and occurs throughout the year.
- Category 2, slight risk, indicates that a threat exists for short-lived, isolated severe storms. This outlook is common during warmer, summer months.
- Category 3, enhanced risk, indicates persistent and widespread storms are likely. Severe storms are expected to be widespread and of varying intensities.
- Category 4, moderate risk, indicates that widespread severe thunderstorms are likely. Numerous tornadoes and thunderstorms are likely. This outlook is less common and is only issued a few times per year.
- Category 5, high risk, indicates widespread severe thunderstorms are expected. The potential for severe and life-threatening weather, including strong or violent tornadoes, some of which may be long-lived and particularly intense, are included in this outlook. This type of alert is very uncommon and occurs a few times per year.
Lightning poses risks of injury or death, and causes property damage as well. Since 2015, the SC Municipal Insurance and Risk Financing Fund, the Municipal Association of South Carolina’s property and casualty insurance program, has received more than 147 lightning property claims with a total cost of $1.1 million.
“Cities and towns should assess the possibility of property damage from lightning, particularly for important infrastructure items such as water and wastewater controls, and develop backup plans in the event of damage,” Heather Ricard, the Municipal Association’s director of risk management services, said.
The vulnerability of property to lightning strikes goes beyond the potential of a direct hit. The field of static electricity that surrounds lightning can damage nearby electronic circuitry and memory devices — items like computer or phone systems, security systems, or the communications and telemetry equipment attached to water towers. Lightning can strike a water tower directly, but its electrical energy can also enter the tower through connected lines.
Municipal risk management assessments for city-owned properties should determine what backups are available for any piece of equipment in case of a strike. They can also mitigate the risk of lightning by making sure that all property is properly grounded, and that no grounding has been disconnected as a result of maintenance work.
Lightning strikes can cause fire or water damage to buildings, and some disaster recovery companies specialize in these kinds of damages. They typically provide measures to stop the spread of damage and begin making repairs. In other instances, damage may be too great for a property to be repaired and capable of being occupied again. In those cases, emergency response companies can provide for needs like temporary electric power, or temporary replacements for phones and computers. All cities and towns should identify potential recovery service providers before they are needed.
For more information, visit the South Carolina Municipal Insurance and Risk Financing Fund webpage.