~ National Lightning Safety Institute ~

General Interest #7

1. ASSUME -

4 CG flashes/km²/yr/average

House is 10 X 20 m² = 1200 m²

Direct strike to house when lightning hits within 10 m

Predicted strike (1200 X4)/1 000 000 =

4.8 X 10 ^-3 or once ea. 200 years

Therefore - 1 out of 200 house will be struck per year.

2. ASSUME -

USA population = 280,000,000

1000 lightning victims/year/average

Odds = 1 : 280,000 of being struck by lightning

For a more complete discussion, see Determining the Probability of Lightning Striking a Facility