• Can Sleeping on Your Rope Cause Damage?
  • Will Dog Urine Harm My Rope?
  • What's the Point of Spotting Highball Boulder Problems?
  • Closet Car: Is it Safe to Store Climbing Gear in Your Vehicle?
  • Do Twists in a Figure-8 Knot Reduce Its Safety?
  • Can a Belay Device Jam Open?
  • Marking the Middle of a Rope
  • Fitting Rock Shoes to Problematic Feet
  • Defining the Cheater Stick and Stick Clip
  • When Your Partner Steals Your Gear...
  • Can You Climb on a Wet Rope?
  • Can You Decrease Fall Factor?
  • Should You Be Allowed to Practice Lead Falls in the Gym?
  • Rope Certifications: Twins, Doubles, or Both?
  • Are Cam Placements Compromised in Wet Rock?
  • What's the Correct Way to Girth Hitch to Your Harness?
  • Choosing Ice Screw Length
  • The Holding Power of Nuts
  • Should You Clip the Belay As Your First Lead Pro?
  • Should I Worry About Spinning Bolt Hangers?
  • Belay-Loop Myth
  • Rock Cleaning Made Easy
  • More, on the EDK
  • Why Not Clip Directly to Cam-Stem Loops?
  • Can You Recommend A Self-Release Knot?
  • What's The Protocol For Naming a Route After Yourself?
  • Is Dropped Gear Still Safe?
  • Can Ropes and Slings Be Contaminated By Essential Oils?
  • Is It Okay to Wear Socks with Rock Climbing Shoes?
  • How Should You Test Gear Placements?
  • Can You Use Adhesive Tape on Ropes, Cords, Webbing?
  • A Better EDK?
  • What's the Difference Between a Double and a Single Rope?
  • Does It Count As a Free Ascent If You Grab the Anchor?
  • Can You Use Cams As Passive Pro?
  • I Found a Rope - Is it Safe to Use?
  • Am I Using a Daisy Chain Wrong?
  • Should I Buy a Plastic or Foam Helmet?
  • Why Doesn't Anyone Climb in Knickers Anymore?
  • Is Weight or Range More Important in Cams?
  • The Mysterious Phenomenon of Rope Shrinkage
  • Worst-Case Scenario - A Factor 2 Fall
  • The Trouble With Glue-In Bolts
  • The Nuts and Bolts of Nuts and Bolts
  • Why Are Climbing Shoes So Expensive?
  • Flaws in the Yosemite Decimal System
  • How Durable is Trad Gear?
  • Using Super Glue on Your Fingers
  • The Worst Gear Ever Invented
  • Rap Ring Strength
  • Spinners and Losers
  • Why Do People Use Oval Biners?
  • Is it Ethical to Clean a New Route?
  • Aid Climbing = Moped Riding
  • Cam Care and Maintenance Guide
  • Will Sweat Harm My Harness?
  • Should You Use Rope or Webbing to Connect to an Anchor?
  • Choosing Between C4s and Friends
  • Can You Lead On a Static Rope?
  • Can I Use Climbing Bolts For Anchors in a Gym?
  • Are My Modified Crampons Safe?
  • Are Falls Held or Breaking Strength More Important In a Rope?
  • Does Poop Harm a Climbing Rope?
  • Are Homemade Draws Reliable?
  • Shopping for Economy Carabiners
  • When You Fly, Can You Carry On Climbing Gear?
  • Can I Trust Fixed Draws?
  • Which Helmet WIll Fit My Big Head?
  • Are Adjustable Leg Loops Useful?
  • Should I clip Ice Screws with Screamers?
  • How do I Make a Bomber Anchor?
  • Can I Modify my Crampon Without Compromising the Integrity?
  • How to Place Ice Tools and Crampons - Will Gadd's Tips
  • How to Place Ice Screws - Will Gadd's Tips
  • Hot Versus Cold Forging
  • Caring For Your Fingertips
  • Are Sewn Slings Stronger Than Knotted Ones?
  • When to Replace Climbing Webbing
  • Using Grip Dip To Color Code Gear
  • The Benefits of Cotton
  • How to Pull a Rappel Rope
  • How to Properly Orient a Carabiner Gate
  • Are My Fuzzy Quickdraws Safe?
  • How to Stretch Climbing Shoes
  • Are 1/2-inch bolts really better than 3/8-inch?
  • Should I Resole My Rock Shoes?
  • How to Hand Drill
  • Lonely Climber Looking for Woman
  • Is My Invented Knot Safe?
  • Difference Between Double and Twin Ropes
  • Dealing With an Argumentative Partner
  • Will Antifreeze Ruin Rope?
  • Why Is a Rack Called a Rack?
  • Rock Shoes For a Big Guy
  • Do They Kill Geese To Get Down?
  • How to Wash a Rope
  • Do Cam Teeth Do Anything?
  • Can I Fix Delaminated Rock Shoes?
  • Can I Mix a Static With a Dynamic Rope for Rappelling?
  • Should You Lower Or Rap Through Anchors?
  • How Should The Middle Man Tie In?
  • How Do I Get a Good Climbing Man?
  • Do Falls Weaken Bolts?
  • Should I Rope Solo?
  • Should I Angle Ice Screws Down?
  • How Should Old Climbers Train?
  • Can I Make a Belay Loop?
  • Reusing Ice Screw Holes
  • Overcoming the Fear of Falling
  • Choosing a Stove Fuel
  • Will My Hiking Boots Work With Crampons?
  • Do Heavy People Shock Load the Rope?
  • Can Offset Cams Subsitute for Regular Cams?
  • Can I Resling My Cams Myself?
  • Are Older Alien Cams Safe?
  • Will sports drinks freeze more slowly than water?
  • The Truth About Climbing Supplements
  • Can I Make My Leashed Tools, Leashless?
  • Rope Stretch Facts
  • How To Cut a Rope Without a Knife
  • Secrets of the Toprope
  • How to Sharpen Crampons
  • Should I Become a Climbing Guide?
  • Preventing Climbing Rope Wear
  • How to Remove an Old Bolt
  • How to Customize Ice Tool Picks
  • Double Rope Facts
  • Do It Yourself Fruit Boots
  • Climbing Rope Sheath Slippage
  • Rockfall Safety
  • Do Screamers Work?
  • Climbing Skin Care
  • Selecting a Gym Rope
  • Quick Links for Climbing
  • Are Russian Cams Good?
  • When To Retire Climbing Gear and Ropes
  • Should I Get a Link Cam?
  • How to Get a Climbing Mate
  • Using Steel Carabiners for Fixed Quickdraws
  • Petzl Tibloc and Climbing Rope Sheath Damage
  • Overcoming Anger
  • Fixing a Spinning Bolt
  • Video Spotlight
    WIDE BOYZ: Spradventure (Full Film)
    WIDE BOYZ: Spradventure (Full Film)
    Whipper of the Month
    Weekend Whipper: Alastair McDowell's Los Indignados (M7) Screamer
    Weekend Whipper: Alastair McDowell's Los Indignados (M7) Screamer

    Worst-Case Scenario - A Factor 2 Fall


    Let's say I'm using a rope that has a maximum impact force of 8.6kN, and the leader takes a serious almost Factor 2 fall. The force on the belayer catching the fall would be less than that on the leader because of the friction on the carabiner through which the rope is clipped. How much less typically? If it's 50 percent less, then the total force on the carabiner is 8.6 + 4.3 = 12.9kN, way less than the strength of the closed carabiner and also way less than the strength of the quickdraw. Is this analysis correct?

    —Steve Pomerance via rockandice.com

    This ruptured 9mm rope held a Factor 2+ fall in 1986—a testament to the severity of such a fall and to the punishment a rope can take.If you really want to know, read Richard Goldstone’s The Standard Equation for Impact Force, based on calculations by Richard M. Leonard and Arnold Wexler, in Belaying the Leader, Sierra Club Bulletin, 1946. Have your 13-year-old daughter explain quadratic equations to you and leave Gear Guy out of it.

    But you asked, so I’m pulled back in.

    First, if you take a Factor 2 fall you won’t have a carabiner in the system because you can only take a Factor 2 by dropping directly onto the belayer with no gear clipped between the two of you. With 20 feet of rope out you fall 40 feet before rope stretch. You can only take a Factor 2 on a multi-pitch route with no protection—if the route has gear (and it holds), you can’t take a Factor 2. Of course, if you fall on a single-pitch route with no gear you hit the ground. I call this a Factor 3 fall.

    But, you said “almost Factor 2” fall. I’ll guess that you are working off the Factor 1.77 drop test used by the CE and UIAA to certify ropes. If you were to take one of these test falls, the impact would be such that you would spend the rest of your life in a diaper, unbothered by carabiner strengths.

    In your question, you hypothesized whether the load would, due to friction on the carabiner, be reduced by half. On Earth, friction on the carabiner holding the fall will be a factor, but to what degree is unknown except in math models. The best estimate—the one posited by eggheads who stay up nights drinking diet Mountain Dew and punching numbers into calculators with key symbols known only to the Pharoahs—is that friction reduces load by one third.

    We know based on practical experience that carabiner friction is real because a 150-pound belayer can “take” a 170-pound leader and the belayer will not get hoisted off the ground. Your assumption—that even a worst-case fall cannot load a carabiner to the point of breaking it—is like that nutty theory of evolution, mostly correct. CE standards require a 20kN minimum breaking strength along a carabiner’s major axis. Even with load multiplication on the anchor you’ll never achieve this high a load.

    Don’t call your agent and cancel your life insurance just yet, however: A misused carabiner, like many a climbing marriage, can break. Cross load or nose hook that biner and it can snap even below the CE-required minimum gate-open strength of 7 kN. Just two issues back [Accident Report, No. 212], we reported on a fall that broke not one, but two carabiners in a row.

    Despite the recent bad news, Gear Guy can report that he once took a Factor 2.1 fall—170-foot fall on 80 feet of rope—which is possible if you screw up in enough ways. The rope was nearly blown into pieces (see photo), but the single non-locking carabiner that caught the fall, though bent, was like GG himself, unbroken. Gear Guy has spoken!

    This article was published in Rock and Ice issue 214.


    Related Articles

    Climb Safe: Fall Factors Explained

    Two Carabiners Break on Leaning Tower

    Climb Safe: Rappelling - Surviving Climbing's Diciest Business


    GOT A QUESTION? E-mail Gear Guy! rockandicegearguy@gmail.com

    Reader's Commentary:

    Don't want to use Facebook, but still want to comment? We have you covered:

    Add Your Comments to this article: