Responses of Lightning Rods to Nearby Lightning 2001-01-2907

In an effort to determine the effectiveness of the sharp tipped lightning rods widely used in the U.S., we carried out a competition between sharp and blunt rods to determine which was preferentially struck by lightning. Over the past eight years, 12 blunt rods participated in cloud-to-ground discharges while none of the nearby rods with sharp tips were struck. Our analysis suggests that the emissions of point discharges from the tips of sharp rods associated with the rapid decrease of the electric field strength around the tips combine to make sharp rods poorer receptors for lightning than are moderately blunt rods.