Category Archives: sports

Unusable Signs – Biking

I took a snap of this sign while on a bike ride yesterday. It appears to be a map of the bike trail. But there are a few problems…

  1. The sign clearly points to the right. The paved bike path continues straight ahead (and turns left in about 200 feet).
  2. That little green triangle in the upper left says “North.” Such a shame that the arrow is pointing to the south, so you have to completely reverse the map in your mind to use it.
  3. Of all the street names listed on the map, none are for streets within viewing distance. I can see 4 street signs from the sign, and none of them are represented ON the sign.

In short, I have no idea what this map is trying to show me, and even if I did, it’s unlikely I’d be able to mentally rotate it with no mistakes.

This is the second municipal sign I’ve seen where the direction you are looking when you read the sign is 180 degrees opposite of what the map displays.

    The Human Factors of Rock Climbing – A matter of life and death

    A tragedy occurred last week in West Virginia where a rock climber died apparently due to a human factors issue with her gear. This text comes from a commenter on Rockclimbing.com:

    The climber was Karen Feher from Midlothian Va. She climbed to the anchor of Rico Suave and clipped in direct. Her setup: She had two thin dyneema slings girth hitched to her harness. At the end of each sling was a locking carabiner held in place with a rubber Petzl keeper…She clipped a locker to each bolt and probably called off belay. I’m unclear if she was going to rappel or lower. It doesn’t matter. She fell to the ground.

    The day after the accident a local climber named Craig (last name?) climbed to the anchor and found a locker on each bolt with a Petzl String still affixed to each one. Both Petzl strings were torn on the side.

    Let me give a little background on the gear so you can understand what seems to have happened:

    Climbers can affix themselves to the wall with equipment that has carabiners on both ends. This allows them to clip themselves to one side and clip the other to the wall. These can come in different varieties, and two types are illustrated below.

    The first type consists of a sewn sling between the two carabiners. It is sewn tightly in multiple places to make sure that it holds tightly to the two carabiners.

    A "quickdraw" with two carabiners
    Notice the larger and smaller holes in each end. One holds a carabiner loosely to the rock while the other holds a carabiner more tightly on the rope end.

    Notice on one side it is sewn so the carabiner hangs loosely and on the other side it is sewn tightly, so that it holds the carabiner almost immobile. The reason for this is to allow the side connected to the wall to swing freely as the rope moves, which keeps the rope movement from jarring or upsetting protection put into the rock. The other end that is connected to the rope keeps the carabiner from moving around and possibly turning sideways.

    The second type (below) consists of a nylon sling doubled over between the carabiners. The benefit of this kind of sling is that it can be changed in length – by doubling and tripling it, it can either be 4′ long, 2′ long, or just a foot long. However, notice both sides are the same. The benefit of having one loose side and one tight side does not exist here. Incidentally, this is the type of sling I use almost exclusively.

    A simple loop connects the two carabiners
    A simple loop connects the two carabiners
    The sling has now been doubled over to shorten it

    There is one way to turn the second type of sling into an approximation of the first type: a rubber band. Not only can you do this with a plain rubber band, there are some specifically sold for this purpose.

    The rubber band holds the rope end tight while allowing the other end to swing freely
    Again, rope holds one end, this time with sling not doubled over

    The problem with this solution lies in the changes to visibility and function that the rubber bands can have when the slings are doubled-over incorrectly.  Click here for a video explaining what can go wrong.

    Essentially, the sling can become almost invisibly connected ONLY by the rubber band. I am sure no one would like to think of hanging 100 feet from the ground by a grocery store rubber band.

    The additional component to the tragedy that prompted this post is that both of her slings were attached only by the rubber band. Climbers build redundancy into their systems to prevent accidents like this, but here both failed.