How Likely Are You To Get Struck By Lightning

When it comes to staying safe from lightning strikes, everything you think you know is probably wrong.

That's the word from weather experts, who worry that outdated advice and persistent myths about thunder and lightning storms may be backfiring, putting people in danger instead of protecting them from harm.

Debunking inaccurate beliefs is vital as we head into summer in North America, the peak season for lightning strikes, said John Jensenius, the lightning specialist for the National Oceanic and Atmospheric Administration, or NOAA.

"There are things we just simply don't recommend anymore," Jensenius said. "People misunderstand them and it puts them in danger."

So far this year, there have been four lightning deaths in the U.S., including a 45-year-old man who was killed after being struck while riding his motorcycle on Interstate 95 in Florida. Last year, there were 20 lightning deaths in the U.S., a record low in a nation where the 30-year average is 51 deaths a year.

Last month, two giraffes were killed in a "billion-to-one" lightning strike in Florida.

Here are the most common myths about lightning strikes and safety:

1. Golfers are most at risk of getting hit.

Not true. Among the 261 people killed by lightning between 2006 and 2013, fishermen accounted for more than three times as many fatalities as golfers — and camping and boating each chalked up almost twice as many deaths as golf.

2. The "30/30 rule" can keep you safe.

It's been years since experts relied on the 30/30 rule, which went like this: If it takes less than 30 seconds to hear thunder after seeing a lightning flash, lightning is close enough to pose a threat, go indoors. And, after the storm ends, wait 30 minutes before resuming outdoor activities. Instead, the new advice is just to go inside either a substantial shelter or a hard-topped metal vehicle at the first sound of thunder, Jensenius said. Once there, experts still recommend waiting a half-hour before going back outside. "The general rule that we use is that if you can hear thunder, you're within striking distance of the storm and you need to go inside right away," he said.

3. If you're caught outside, assume the "lightning squat."

"The idea was to squat down low with your two feet together," Jensenius said. "Some had you putting your hands over your head or your ears, basically to get yourself into a ball." But that's also wrong. People are endangered as much by ground lighting as they are by a direct strike. For instance, lightning can hit a tree and then spread along the surface of the earth, Jensenius said. If you're crouching on the ground, you're likely to get hit. Again, the best advice is to head to shelter at the first sign of a storm.

4. Just go ahead with your plans during a lightning storm.

The biggest mistake most people make is not being willing to cancel or postpone activities when dangerous weather crops up, Jensenius said. Men, who make up more than 80 percent of lightning fatalities, are notoriously unwilling to postpone a hike or head back to shore on a fishing trip, he noted. But that stubbornness may be a deadly decision.

5. You'll hear a storm in time to get to safety.

People are able to hear thunder from about 10 miles away, Jensenius said. But any number of factors can interfere with the warning. "In many cases you can't hear it that far because of background noise," he said. "You won't hear it if you're near a highway or in a crowd at a fair or a ball game. And if the wind is blowing, it would muffle the sound."

Bottom line: Don't take chances with lightning. The odds of being struck may be one in a million in a given year and one in 10,000 over a lifetime, but it's better not to be that one.

This story was first published on NBCNews.com in 2014.