Thunderstorms are dangerous because they contain lightning, which kills more people than tornadoes or hurricanes. To remain safe during a thunderstorm, it is recommended to go inside a sturdy building or a vehicle, and to stay inside for at least thirty minutes after the last rumble of thunder is heard. It is also important to avoid using telephones or electrical equipment, taking showers or baths, tall isolated trees, water, high ground, and metal objects.
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