Uncontrolled pendulum swing

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Dave1960_Gorge

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I have had a few dents from tree work in the last 12 years: cracked knee cartilage, rotator cuff damage, pruning hook hanging from my forearm — but I went for a ride just last Thursday that put me in the hospital till Tuesday.

ANSI Z133, 8.1.25: “The tie- in position shall be well above the work area so that the arborist shall not be affected by an uncontrolled pendulum swing in the event if a slip”.

Now, if you are doing a pruning or removal of a hardwood with a low wide crown, you have to address the unavoidable, which I though I was doing, right up until I snacked I to the trunk.

Ash, around 40 by 50 ft, actually had pruned it about 5 years earlier. Had poor firm after regrowing from ice storm damage. This time the homeowner wanted it way down, because they were eventually going to remove it but not just yet. So it was basically a removal but leaving about 15 ft of trunk and some low branches.

Moving right along, I was down to three spars, one with a pulley and load line and two with climbing ropes, each hitched to a ZigZag. Limb walked out the big low limb cutting branches; plan was to rig down the last three and then chunk it on the way back. My two ropes gave me nice stability: I could walk out, jabbing a spur here and there, working both ZigZags with one hand and flipping my wire core lanyard around the mostly vertical branches as I went.

Last branch: this time my lanyard was looped on a stub... you see where this is going. The second I pushed over the 30 ft branch, I fell back and seemingly at the same time felt my helmet smack into the main trunk 15 ft away.

I lowered myself another 6 ft to the ground, and decided to call it a day due to the bell ringing and my left leg feeling funny.

Long story short, I drove myself to the ER 3 1/2 hours later with my leg out the window resting on the rear view mirror because it wouldn’t bend, and was as hard as wood.
On the mend now, after 3 operations; 6-8 weeks and I might be climbing. Compartment Syndrome is no bueno; if more time has gone by before surgery, could have lost my leg.

If only I had choked the limb instead of looping the stub, I wouldn’t be trying to run my business from bed with my leg up.
Because I was paying into Workman’s Comp (as the owner of my LLC) state OSHA is involved. Guess I’ll see what happens.

looks better now.
 

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I have had a few dents from tree work in the last 12 years: cracked knee cartilage, rotator cuff damage, pruning hook hanging from my forearm — but I went for a ride just last Thursday that put me in the hospital till Tuesday.

ANSI Z133, 8.1.25: “The tie- in position shall be well above the work area so that the arborist shall not be affected by an uncontrolled pendulum swing in the event if a slip”.

Now, if you are doing a pruning or removal of a hardwood with a low wide crown, you have to address the unavoidable, which I though I was doing, right up until I snacked I to the trunk.

Ash, around 40 by 50 ft, actually had pruned it about 5 years earlier. Had poor firm after regrowing from ice storm damage. This time the homeowner wanted it way down, because they were eventually going to remove it but not just yet. So it was basically a removal but leaving about 15 ft of trunk and some low branches.

Moving right along, I was down to three spars, one with a pulley and load line and two with climbing ropes, each hitched to a ZigZag. Limb walked out the big low limb cutting branches; plan was to rig down the last three and then chunk it on the way back. My two ropes gave me nice stability: I could walk out, jabbing a spur here and there, working both ZigZags with one hand and flipping my wire core lanyard around the mostly vertical branches as I went.

Last branch: this time my lanyard was looped on a stub... you see where this is going. The second I pushed over the 30 ft branch, I fell back and seemingly at the same time felt my helmet smack into the main trunk 15 ft away.

I lowered myself another 6 ft to the ground, and decided to call it a day due to the bell ringing and my left leg feeling funny.

Long story short, I drove myself to the ER 3 1/2 hours later with my leg out the window resting on the rear view mirror because it wouldn’t bend, and was as hard as wood.
On the mend now, after 3 operations; 6-8 weeks and I might be climbing. Compartment Syndrome is no bueno; if more time has gone by before surgery, could have lost my leg.

If only I had choked the limb instead of looping the stub, I wouldn’t be trying to run my business from bed with my leg up.
Because I was paying into Workman’s Comp (as the owner of my LLC) state OSHA is involved. Guess I’ll see what happens.

looks better now.
Holy ****
 
Holy ****
Indeed.

Got another call from OR OSHA:
they are asking that I write up an accident report ; I take that as a good sign. Rules are less strict for small companies with a few employees. Not saying I did not put effort into safety and training, but larger companies need to keep proper written records of all of it.

I have concluded that I need to put more effort into encouraging groundies to recognize practices that are “ pushing the envelope” and tell me. I actually had mentioned that to him, with the example of my life line in a top I am about to cut.

This particular guy was a new guy and first day on the job ( just the two of us). He actually asked later: “Did you mean to do that?”

So a ways to go with him! He did hump that brush like mad, so part way there.
 
Maybe I'm not reading something correctly but it sounds like YOU need to put more effort into yourself recognizing practices that are "pushing the envelope". Are you saying that you expect ground guys to tell you when you're doing your job incorrectly? Don't get me wrong....safety is everyone's responsibility but you are responsible for your job site and everything that happens out there....no matter who does it or how small of an action it is. It's you who failed. I don't want to sound like a **** but I am a **** about safety because I'm trying to save peoples lives. I am just like this with my guys because it matters. You control everything on your job site....or you don't. This never should have happened. I hope you don't get a big fine for it.
 
Appreciate the comment. I spent the last two weeks beating myself up over what happened. I was angry. Pissed.
But then you accept it and it’s not likely I will screw up again, at least in the same way.

I have told my crew that we all are responsible for safety. It is just a way of thinking, and if something is off, anyone can stop the show at any time. No assumptions that the more skilled guys always know what they are doing.

I have been climbing seriously for 12 years. Only serious injury (knock on wood). That does not mean there haven’t been close calls known and unknown.
Yes, responsibility is ultimately mine, but I wasn’t thinking about how it would feel to have 49 staples in my leg for two weeks when I screwed up. I didn’t think about that at all — and that was the problem.

I just put the story up because I thought other climbers might stop and think for a second about their practices . PNW ISA wants me to write a piece and I will.

Don’t give a rip if someone out there feels “superior” to me because they would never do something that stupid. And that was just the attitude that could have killed me, if a smidge here or there had been different—-or stopped the thing from happening.

Peace
 
Appreciate the comment. I spent the last two weeks beating myself up over what happened. I was angry. Pissed.
But then you accept it and it’s not likely I will screw up again, at least in the same way.

I have told my crew that we all are responsible for safety. It is just a way of thinking, and if something is off, anyone can stop the show at any time. No assumptions that the more skilled guys always know what they are doing.

I have been climbing seriously for 12 years. Only serious injury (knock on wood). That does not mean there haven’t been close calls known and unknown.
Yes, responsibility is ultimately mine, but I wasn’t thinking about how it would feel to have 49 staples in my leg for two weeks when I screwed up. I didn’t think about that at all — and that was the problem.

I just put the story up because I thought other climbers might stop and think for a second about their practices . PNW ISA wants me to write a piece and I will.

Don’t give a rip if someone out there feels “superior” to me because they would never do something that stupid. And that was just the attitude that could have killed me, if a smidge here or there had been different—-or stopped the thing from happening.

Peace

It sounds like you learned something from this. I'm glad you are healing. I hope this never happens to you again.
 
Hope that happens. Safety has to be the number one consideration. But you are also thinking about the job plan, training the new guy, the clock, and how that next 30 ft branch is gonna lay down flat with its butt to the chipper like the last one. My two ropes and lanyard made me as stable as sitting in a desk chair. The ground was “only” about 16 ft down. Weather was perfect. I felt good. And yet...
 
Hope that happens. Safety has to be the number one consideration. But you are also thinking about the job plan, training the new guy, the clock, and how that next 30 ft branch is gonna lay down flat with its butt to the chipper like the last one. My two ropes and lanyard made me as stable as sitting in a desk chair. The ground was “only” about 16 ft down. Weather was perfect. I felt good. And yet...
You're right. That is some of the stuff you're thinking about. But all of that is your job. The situation doesn't really matter to me. I never think about the clock. If you blow it on the bid....you just maybe blow it.....but you need to be thinking about what is in front of your face right now.
 
Hope that happens. Safety has to be the number one consideration. But you are also thinking about the job plan, training the new guy, the clock, and how that next 30 ft branch is gonna lay down flat with its butt to the chipper like the last one. My two ropes and lanyard made me as stable as sitting in a desk chair. The ground was “only” about 16 ft down. Weather was perfect. I felt good. And yet...
You're right. That is some of the stuff you're thinking about. But all of that is your job. The situation doesn't really matter to me. I never think about the clock. If you blow it on the bid....you just maybe blow it.....but you need to be thinking about what is in front of your face right now.
you hit it on the nose.
Paying attention to what is in front of your face is key. Literally , thinking about what is right around you and staying in the moment is how I improved my skills over time and stayed in one piece.

That is why it is maddening to me that I continued my approach on that limb as I worked farther and farther out from under my tie- ins without changing the fall protection system to adapt, given the height of the tie- ins.

I was trying to fill in reasons for why I did that. None of the ones I listed are valid reasons. I really can’t recall what I was thinking, but I can assume it wasn’t considering those two variables at the time as determinative of my next action. Somehow that had become disconnected.

It’s like the punchline you give to a joke about someone’s bad decision that ended up biting them on the butt: “I didn’t know that would happen”, when it is obvious to a reasonable person that it could, with a high probability.

It’s funny when it has a minor consequence, and YouTube is full of clips of people juggling their phone over a railing ( and dropping it), jumping over a low obstacle ( and tripping), firing a gun with a loose grip ( and getting a black eye. So I have joined the club. Those people didn’t want those outcomes, but they got bitten.

I suppose it is worse for me, because I knew better and the possible consequence was worse.

Need to go plug in my portable negative pressure machine to recharge it—- the warning beep is probably what woke me up. I get to walk around with it hanging from my neck for another week until the staples come out. Tubing goes from what is essentially a little aquarium pump, that is working in reverse to keep the dressing sucked down over the 24 in incision, down my pants. It helps to keep the wound closed and bacteria out; in the hospital, the tube was inside the wound, and helped drain it. And you don’t get to wear pants there. I got to watch my “precious bodily fluids” fill a reservoir for days.

Just putting this out there ( along with the pic a while back of the open wound draining ) to bring home to whomever reads this what the consequence may be for a climber ignoring what is vitally important.
 
Hope that happens. Safety has to be the number one consideration. But you are also thinking about the job plan, training the new guy, the clock, and how that next 30 ft branch is gonna lay down flat with its butt to the chipper like the last one. My two ropes and lanyard made me as stable as sitting in a desk chair. The ground was “only” about 16 ft down. Weather was perfect. I felt good. And yet...

you hit it on the nose.
Paying attention to what is in front of your face is key. Literally , thinking about what is right around you and staying in the moment is how I improved my skills over time and stayed in one piece.

That is why it is maddening to me that I continued my approach on that limb as I worked farther and farther out from under my tie- ins without changing the fall protection system to adapt, given the height of the tie- ins.

I was trying to fill in reasons for why I did that. None of the ones I listed are valid reasons. I really can’t recall what I was thinking, but I can assume it wasn’t considering those two variables at the time as determinative of my next action. Somehow that had become disconnected.

It’s like the punchline you give to a joke about someone’s bad decision that ended up biting them on the butt: “I didn’t know that would happen”, when it is obvious to a reasonable person that it could, with a high probability.

It’s funny when it has a minor consequence, and YouTube is full of clips of people juggling their phone over a railing ( and dropping it), jumping over a low obstacle ( and tripping), firing a gun with a loose grip ( and getting a black eye. So I have joined the club. Those people didn’t want those outcomes, but they got bitten.

I suppose it is worse for me, because I knew better and the possible consequence was worse.

Need to go plug in my portable negative pressure machine to recharge it—- the warning beep is probably what woke me up. I get to walk around with it hanging from my neck for another week until the staples come out. Tubing goes from what is essentially a little aquarium pump, that is working in reverse to keep the dressing sucked down over the 24 in incision, down my pants. It helps to keep the wound closed and bacteria out; in the hospital, the tube was inside the wound, and helped drain it. And you don’t get to wear pants there. I got to watch my “precious bodily fluids” fill a reservoir for days.

Just putting this out there ( along with the pic a while back of the open wound draining ) to bring home to whomever reads this what the consequence may be for a climber ignoring what is vitally important.
I hope you get back to 100% and keep kicking some ass. I will say that I have done this job for a long time and when I'm training people, I tell them that the most important thing is to be able to predict what will happen next. We don't have to compare who is better at doing this or that. The last thing that you misjudged in front of you is what is going to kill you or gravely injure you. One of my sons told me a week or two ago that he couldn't believe I'm still alive. I'm kind of the older guy now who does all of our most dangerous stuff on any of our crews. There is no secret. I'm not that much better than anyone. I'm just very good at predicting what will happen because of experience.
 
Thanks for the thoughtful reply Mike.
Just sent my report to OR OSHA. May the gods in Salem have pity on me!

Writing the report forced me to do some analysis of my actions and comparing them to the ANSI Z133 standard (I figured that was a good idea anyway). The instructions were to describe the accident, and how it could be prevented in the future. If I had moved a false crotch along that limb with a third climbing line as fall protection I would have been good.

My positioning lanyard was in effect being used as that once I was out from under my two climbing lines on the spars— and there were TWO MORE things wrong with that.

Every time I moved, I had no tie in while I was clipping and clipping my lanyard. Then, at the end, I was at or above the rigging point of the spar (the stub), with my lanyard ( fall protection system) just draped behind it.

I am still amazed I was being so unsafe. And I felt really stabile out on that limb.
 
Don't mean to flog this to thread to death, but I was able to get out to the site and take some pics and measurements yesterday -- mainly because I could bend my left leg now to 90 degrees and get it into the Jeep (pretty small cabin in that old Cherokee for a 6 ft. 3 guy). Not ready to work the stiff clutch n my 79 F-350 dump just yet.

The pic shows the scene pretty well. I tied flagging on to 8 ft. sticks at 1 ft. intervals; its being held where I was standing, and you can see the two stubs at the end of the limb; the longer one was the last branch I cut, and the shorter one was the one I had my lanyard looped on. Given I was about 2 ft. away from the short stub, my lanyard was at a slightly downward angle or it wouldn't have been on the one foot stub at all.

My feet were at just over 14 ft. off the ground, and 16 ft. below the two spars which were at 29 and 30 ft. off the ground (measured those with a laser range finder). Horizontal distance to the center of the 20 in. trunk was 10. 5 ft., and 11.5 ft. to the spars. The south spar (30 ft. tall) was 4 ft. from the center of the tree, and the west 1 ft., but after doing the math, they were essentially the same distance away. You can see the rigging spar with a sling and pulley on it.

Given that I was tied in at about 3 ft. above my boots (at 17 ft.), my center of mass was 13 ft. below the taller 30 ft. spar 11.5 ft. away. I ended up with my head a little below the limb fork (9.5 ft. off the ground)-- first thing I remembered after the fall was looking at my ropes looping up and over the limb; this put my feet about 3 1/2 ft. off the ground, and my waist 6 1/2, for a vertical drop of about 10.5 ft. The swing was interrupted by the trunk a at 9.5 ft. from my starting point, 2 ft. short of the bottom of the pendulum swung, so I was at near maximum velocity. Leaving it up to my cousin to calculate the foot pounds or whatever and what the force was exerted on my thigh as I decelerated in the space of a few inches. Like they say, its not the height of the drop, its hitting the ground that gets you. In this case, I doubt the ash moved at all; might as well have been a brick wall.

So, question:

At what point would you guys have rigged a false crotch as you advanced out on the limb?
That was my idea for discussing prevention in my self report to OR OSHA. IMG_4427.JPG

And, do you think you would have done this (or have done it) in the past?
 
Appreciate the comment. I spent the last two weeks beating myself up over what happened. I was angry. Pissed.
But then you accept it and it’s not likely I will screw up again, at least in the same way.

I have told my crew that we all are responsible for safety. It is just a way of thinking, and if something is off, anyone can stop the show at any time. No assumptions that the more skilled guys always know what they are doing.

I have been climbing seriously for 12 years. Only serious injury (knock on wood). That does not mean there haven’t been close calls known and unknown.
Yes, responsibility is ultimately mine, but I wasn’t thinking about how it would feel to have 49 staples in my leg for two weeks when I screwed up. I didn’t think about that at all — and that was the problem.

I just put the story up because I thought other climbers might stop and think for a second about their practices . PNW ISA wants me to write a piece and I will.

Don’t give a rip if someone out there feels “superior” to me because they would never do something that stupid. And that was just the attitude that could have killed me, if a smidge here or there had been different—-or stopped the thing from happening.

Peace
I'm glad you posted. I learned from your mistake. Not easy to own up and be honest about what happened and your part in it.
 
you are also thinking about the job plan, training the new guy, the clock, and how that next 30 ft branch is gonna lay down flat with its butt to the chipper
There's your mistake right there. Sorry to pile it on, but when you're operating in the tree, your life hanging on a rope and you have a saw in your hand, every other thing on earth needs to be put out of mind, secondary to your immediate situation. With every move on the limb & every cut you anticipate, you need to KNOW: if I do this, what will be the reaction--of the saw, the rope, your body in its new location, etc.

Glad to hear you'll be okay.
 
Don't mean to flog this to thread to death, but I was able to get out to the site and take some pics and measurements yesterday -- mainly because I could bend my left leg now to 90 degrees and get it into the Jeep (pretty small cabin in that old Cherokee for a 6 ft. 3 guy). Not ready to work the stiff clutch n my 79 F-350 dump just yet.

The pic shows the scene pretty well. I tied flagging on to 8 ft. sticks at 1 ft. intervals; its being held where I was standing, and you can see the two stubs at the end of the limb; the longer one was the last branch I cut, and the shorter one was the one I had my lanyard looped on. Given I was about 2 ft. away from the short stub, my lanyard was at a slightly downward angle or it wouldn't have been on the one foot stub at all.

My feet were at just over 14 ft. off the ground, and 16 ft. below the two spars which were at 29 and 30 ft. off the ground (measured those with a laser range finder). Horizontal distance to the center of the 20 in. trunk was 10. 5 ft., and 11.5 ft. to the spars. The south spar (30 ft. tall) was 4 ft. from the center of the tree, and the west 1 ft., but after doing the math, they were essentially the same distance away. You can see the rigging spar with a sling and pulley on it.

Given that I was tied in at about 3 ft. above my boots (at 17 ft.), my center of mass was 13 ft. below the taller 30 ft. spar 11.5 ft. away. I ended up with my head a little below the limb fork (9.5 ft. off the ground)-- first thing I remembered after the fall was looking at my ropes looping up and over the limb; this put my feet about 3 1/2 ft. off the ground, and my waist 6 1/2, for a vertical drop of about 10.5 ft. The swing was interrupted by the trunk a at 9.5 ft. from my starting point, 2 ft. short of the bottom of the pendulum swung, so I was at near maximum velocity. Leaving it up to my cousin to calculate the foot pounds or whatever and what the force was exerted on my thigh as I decelerated in the space of a few inches. Like they say, its not the height of the drop, its hitting the ground that gets you. In this case, I doubt the ash moved at all; might as well have been a brick wall.

So, question:

At what point would you guys have rigged a false crotch as you advanced out on the limb?
That was my idea for discussing prevention in my self report to OR OSHA. View attachment 897466

And, do you think you would have done this (or have done it) in the past?

I understand that you are trying to give as accurate of a description as you can but the answer to your question doesn't really rest with all these measurements and calculations. There are a number of things you could have done differently. Having 2 ropes or 10 ropes doesn't matter if none of them save your life. Just looking at that pic.....you should have removed that limb much earlier in the climb while you still probably had some better options above you. But having your scare strap in the proper place would have saved you....even if you didn't have a rope at all. Don't over-think your mistake with a bunch of math. You just need to be tied-in safely and plan your climb a little better so you don't create this kind of a situation.
 
I understand that you are trying to give as accurate of a description as you can but the answer to your question doesn't really rest with all these measurements and calculations. There are a number of things you could have done differently. Having 2 ropes or 10 ropes doesn't matter if none of them save your life. Just looking at that pic.....you should have removed that limb much earlier in the climb while you still probably had some better options above you. But having your scare strap in the proper place would have saved you....even if you didn't have a rope at all. Don't over-think your mistake with a bunch of math. You just need to be tied-in safely and plan your climb a little better so you don't create this kind of a situation.
No disagreement with your take on it. If the climber sees that a bad swing or fall is possible, they have to fix that by changing the tie-in arrangement. A false crotch where I was working would have been a good choice .

There wasn’t a good tie-in point above the limb except for the spars, so I planned to do the rest of the tree first, take apart the low limb, then chunk the spars off to the side.

My plan from the beginning should have included changing the support system once I was out on the limb a ways. Or I should have recognized the problem later on and fixed it then.

Coulda shoulda woulda
 
I'm glad you posted. I learned from your mistake. Not easy to own up and be honest about what happened and your part in it.
Thx! Not fun turning away work and putting off jobs I already have. Found a contract climber but he only has two days a week. I draw from three ground guys but they only have a few days a week . I was used to trading off climbing and ground work with my regular climber but he works for other outfits now.

still better off than the alternative
 
I made the very same mistake two years ago, at 40-50ft up, and twice as far out a limb - chose an unsafe branch stub to tie into, rather than getting the lanyard under the main limb I was reducing, and the dynamic movement of taking the tip popped my lanyard off and sent me swinging all the way back to the trunk, 200t flailing in one hand. Got away with only a scrape on the elbow, but it could have been so much worse.

I strongly second Old CB’s comment about staying “in the zone” while in the tree. There is absolutely no room to be elsewhere mentally. It’s one of my favorite things about climbing, actually - it forces me to let everything else go. Time compresses on itself, there is no past, just the present. The future extends only as far as the next few chess moves in my pre planned match against the tree.

Also, a polesaw is your friend in these situations. In this particular case, with a small limb so close to the ground, you could have easily flung a running bowline around it towards the tip, and safely removed the branch from the ground, saving yourself the limb walk altogether...
 
A couple more thoughts about safety:

After my uncontrolled pendulum experience, I quickly switched to incorporating a simple lowering/rescue redundancy into my primary basal anchor, whenever possible. Petzl Rig makes it pretty idiot proof, but a little portawrap or even a friction hitch can work just fine. Never have had to use it, and hope I never do, but the thought of dangling broken and unconscious from a rope, unable to get myself down to medical assistance is terrifying enough to hedge against.

I’ve also become a bit obsessive about cleaning up any and all sharp branch stubs in my vicinity before removing any dynamic pieces. As I regained my composure in the moments after my big swing, the good luck for which I found myself most profoundly grateful was having missed a spear-like broken branch less than a meter from my point of impact with the trunk. Would have skewered me like a grotesque human shrimp.
 
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