Climbing instructor Carl Keene has seen a lot of unsafe (and even downright peculiar) behavior in his years of mountain climbing.

“There was this time we saw a guy climbing up the rocks and he was naked,” Keene says. “I don’t know what he was doing up there naked. I didn’t want to know. He didn’t have any equipment (and) he fell 50 feet.” 

Keene saw another man fall 75 feet from a cliff and (like climber sans clothes) miraculously survive. “He was not paying attention to what he was doing,” Keene says. After unhooking himself from his climbing rope, the climber tried to jump from one ledge to another — and missed.

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Keene operates Rocky Mountain Climbing Gear in Coeur d’Alene, Idaho, where he also teaches rock-climbing techniques. He has more than 15 years of experience scaling the Rockies and other mountain regions. Most injuries occur among inexperienced climbers, he says, but even experienced climbers can get hurt if they’re careless or reckless.

Mountain climbing is serious business: A mistake at the wrong moment can kill you. With this in mind, here are some key safety tips from Keene, veteran climber Laura Snider of climbing.com and Duane Raleigh, editor and chief of Rock and Ice Magazine in Colorado.

Get trained. Don’t depend more on your confidence than your competence. If you’re a novice, “you want to go to a facility that’s qualified to train you,” Keene says. “The most common mistake is people climb with their friends who’ve done some climbing, then they go out climbing by themselves and think they know it all.”

Take a pass on free climbing. “Free climbing is not as popular as it was a few years ago and people were constantly getting hurt doing it,” Keene says. “With free climbing you have no safety gear at all, no harness. People would say it’s all natural, but I say ropes are not real expensive. Use them.”

Wear a helmet. Slamming into the wall and dodging loose rock are regular climbing hazards. A helmets can save your skull.

Wear gloves if you’re belaying and save your hands from a nasty burn.

Use your own equipment, and check it every time before you climb. On climbing.com, Laura Snider advises climbers not to trust all fixed slings, noting that two young climbers were killed in 2009 when a webbing rappel anchor failed.Just because someone else rapped off that rat’s nest doesn’t mean it’s safe to use again. Make sure to check for sun damage (fading or crackling) and fraying. Also, make sure a critter hasn’t chewed through the slings hidden behind a tree or rock,” she says. Keene concurs that you should put in your own anchor mounts: “I personally don’t use existing anchors. I don’t trust them. I don’t know who put them in. I trust my own equipment.”

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Belay with the right rope.If you’re the belayer — that is, the one lowering your partner — be sure your rope isn’t too short. “The number one cause of accidents is being dropped by the belayer and falling from the end of your climbing or rappel rope,” says Raleigh.

Use standard climbing commands. For instance, yell “slack” when you need extra rope to make the first move or finish taking apart your belay anchor, and yell “off belay” when you’re tied in to the rock with a personal anchor and no longer need the belayer, according to rei.com. Many accidents stem from a lack of communication between climbers, Keene says. Always call your partner by name — some accidents have occurred because someone from another climbing party replied.

Double-check all your knots. Your and your partner should confirm the rope is threaded correctly through the belay,that the locking carabineers in the system really are locked, and that the knots are tight, tied correctly and looped through the harness correctly — and don’t forget the very last knot. “Forgetting to tie a knot at the end of the rope” can be fatal, says Raleigh. “That happens all the time and kills many climbers every year. It’s completely avoidable. Just tie the proper knot at the end of the rope.”

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Don’t tie into belay anchors with just a daisy chain. Daisy chains are designed to support only body weight and must not be used with the belay. To avoid belay problems, “tie into your anchor with the stretchy, shock-absorbing lead rope,” advises Snider.

Whenever possible, descend by foot rather than rappelling. As The American Alpine Institute explains, “There are more climber injuries and fatalities from mistakes rappelling than from any other place in all of climbing.”

Climbing is as close as we can come to flying,” said aviator and alpinist Margaret Young. And if you take climbing safety seriously, hopefully the flying will be pure pleasure.

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Steve Evans, MA, is an award-winning journalist with more than 20 years experience in daily news, investigative, health and business journalism. Among other jobs, he has served as managing editor of the Central Virginia Newspaper Group, as a senior writer for SNL Financial and as a staff writer for The Progress Index and the Richmond Times-Dispatch.