4 ms·

I am currently building a house, and there are large portions of it that have a >25ft drop from rooftop to the ground below. That means the workers on the roof

by newmac 7y ago

I am currently building a house, and there are large portions of it that have a >25ft drop from rooftop to the ground below. That means the workers on the roof or upper floor need to wear proper fall protection. Depending on the job that can often by a harness system. I was surprised that because of the height of the potential fall, we needed a "rescue plan". In other words: arresting the fall is only half the job. The result was quite a bit of extra expense for us (because of the site conditions, we need to keep a hydraulic lift available), but when I read about how quickly suspension trauma becomes an issue, I could understand why the safety regulations are written as they are.

planteen 7y ago
That's why you would never catch me on a rope without at least a pair of loops of smaller diameter rope that I could tie into Prusik knots and self-rescue. Those pieces of rope are almost weightless. There's no reason not to have a pair with you when you get on rope.
- maxerickson 7y ago
  Featured in a James Bond stunt: https://www.youtube.com/watch?v=8FDX6_BSas8 https://www.youtube.com/watch?v=8FDX6_BSas8 (The clip is from "For Your Eyes Only" but has music from some other bond film dubbed over it)
  - TeMPOraL 7y ago
    Wow, apparently you can pull yourself up by your own bootstraps!
- mirimir 7y ago
  Why not tie an Alpine Butterfly in advance? Isn't that more secure than Prusik or Klemheist? Or does it weaken the main rope too much? Or are you saying to use a pair of Prusik knots to self rescue, by climbing the rope?
  - JshWright 7y ago
    Yeah, the parent comment is talking about using a pair of Prusiks to ascend (or to at least make loops you can use to stand). An Alpine Butterfly can't be moved, so it's not especially useful in many applications.
    - planteen 7y ago
      Yep exactly. I'm talking about a pair of Prusiks to climb the rope. Of course ascenders/Jumars are even better. :)
      - mirimir 7y ago
        Thanks. So when I was a kid, they made us climb a ~3 cm rope about 20 meters. With no aids, and just a padded mat for protection.
        JshWright 7y ago
        20m? That's a fatal fall...
        mirimir 7y ago
        OK, upon reflection, more like 8-10 meters. The ceiling height in the gymnasium. It was a long time ago, and what I mostly remember is the fear of falling. And the rope burns.
- takk309 7y ago
  Try getting a prusik system set up when your tie in point is in the middle of your back as most construction harnesses are set up. It makes it much harder to self rescue. Side note, one of my favorite ways to get up a rope when hanging in free space is to walk the rope. https://www.youtube.com/watch?v=gAzXYVdskFE https://www.youtube.com/watch?v=gAzXYVdskFE
  - module0000 7y ago
    Also, in those times when you need a prusik, there is a less-than-tiny chance you are hurt. EG: you're trying to place your cam, and instead you take a 40 foot drop before your last cam arrests your fall by sending your body directly into the face. Prusiks are more difficult to tie(and ascend!) when your hands are coated in your own blood, etc.
    - takk309 7y ago
      I have, thankfully, never had to try to tie a prusik with my hands covered in blood. If you had to do that, it sounds like a brutal fall.
    - planteen 7y ago
      Yeah for sure, injury changes things. You see rock climbers needing rescue often enough when they could have self-rescued by a pair of Prusiks and ascending the rope. I've heard of a rock climber using an ATC (rappel device) as an ascender, by kicking off the wall and moving the rope up a few inches. They were near complete exhaustion when they got up to the top - Prusiks would have made the job so much easier. Of course a pair of ascenders/Jumars is best, but add some weight. Most people (outside of cavers) don't plan on climbing up a rope with single rope technique, so it's not something that is practiced very much. I'm not really sure why. I'd be super nervous as a climber if I only could go one way on a rope. I guess alpinists practice it some for self-rescue out of a crevasse. Cavers use the rope as a nylon highway, so you know how to switch from rappel to climb, climb to rappel, and how to pick-off an injured party from the rope (all of those in space, where you can't take your weight off the rope at all).
Bartweiss 7y ago
It's always surprising to me how fall risks operate in the world of OSHA compared to rock climbing. There's an entire domain where people take good-sized falls as an everyday event, just sort of sitting in parallel with the domain where they're considered a major risk needing emergency-response measures. Obviously, some of that is a real difference in situation. Construction falls are unplanned and happen under all sorts of odd circumstances, and people are quite often injured during their falls. Climbers have someone managing the other end of their rope at all times, on a system that makes lowering them to the ground straightforward. But other differences seem absolutely pointless. The "suspended by your groin, legs hanging straight down" posture of construction harnesses massively accelerates suspension trauma, while climbing harnesses pull the legs up and keep pressure on large muscles. And there are companies starting to use that design for safety gear, so it's not a regulatory issue - it just somehow took decades to cross the gap.
- takk309 7y ago
  I big difference between a climbing harness and a construction harness is the tie in point. Climbing it is fine to have that point in front of the user. For construction, having the rope constantly in front of you would be a real inconvenience. By tying in on the back, the harness will hold the user in a different orientation just due to the way weight is distributed.
  - Bartweiss 7y ago
    That's definitely part of it; climbing harnesses tend to support you in a position that's great for suspension trauma, but involves a pretty inconvenient rope. They're also waist-and-hip only, and while they'll reliably hold a climber through a flip, it doesn't sound great for chaotic, confined-space falls where you might stay upside down. The newer generation of construction harnesses are still back-clipped and full-body though - a short strap runs from the waist to the back clip to redistribute weight without normally being in front of you. Presumably getting that working smoothly and safely was an extra engineering hurdle, but I'm still surprised harnesses went so long without even including waistbands.
- module0000 7y ago
burfog 7y ago
Falls from far less than that height can kill. If it is safe to be at 10 feet without that equipment, then it is safe to be at 1000 feet without that equipment. IMHO, the cutoff is just what the construction industry was willing to tolerate. The whole thing is a lobbyist battle between the construction industry and the safety equipment industry.
- newmac 7y ago
  I think that at a lower height, a rescue is considered to be easier. 10 ft would still require a safety program, it just wouldn't be fall arrest, more likely prevention (scaffolding)

by newmac 7y ago

planteen 7y ago

That's why you would never catch me on a rope without at least a pair of loops of smaller diameter rope that I could tie into Prusik knots and self-rescue. Those pieces of rope are almost weightless. There's no reason not to have a pair with you when you get on rope.

maxerickson 7y ago
Featured in a James Bond stunt: https://www.youtube.com/watch?v=8FDX6_BSas8 https://www.youtube.com/watch?v=8FDX6_BSas8 (The clip is from "For Your Eyes Only" but has music from some other bond film dubbed over it)
- TeMPOraL 7y ago
  Wow, apparently you can pull yourself up by your own bootstraps!
mirimir 7y ago
Why not tie an Alpine Butterfly in advance? Isn't that more secure than Prusik or Klemheist? Or does it weaken the main rope too much? Or are you saying to use a pair of Prusik knots to self rescue, by climbing the rope?
- JshWright 7y ago
  Yeah, the parent comment is talking about using a pair of Prusiks to ascend (or to at least make loops you can use to stand). An Alpine Butterfly can't be moved, so it's not especially useful in many applications.
  - planteen 7y ago
    Yep exactly. I'm talking about a pair of Prusiks to climb the rope. Of course ascenders/Jumars are even better. :)
    - mirimir 7y ago
      Thanks. So when I was a kid, they made us climb a ~3 cm rope about 20 meters. With no aids, and just a padded mat for protection.
      - JshWright 7y ago
        20m? That's a fatal fall...
        mirimir 7y ago
        OK, upon reflection, more like 8-10 meters. The ceiling height in the gymnasium. It was a long time ago, and what I mostly remember is the fear of falling. And the rope burns.
takk309 7y ago
Try getting a prusik system set up when your tie in point is in the middle of your back as most construction harnesses are set up. It makes it much harder to self rescue. Side note, one of my favorite ways to get up a rope when hanging in free space is to walk the rope. https://www.youtube.com/watch?v=gAzXYVdskFE https://www.youtube.com/watch?v=gAzXYVdskFE
- module0000 7y ago
  Also, in those times when you need a prusik, there is a less-than-tiny chance you are hurt. EG: you're trying to place your cam, and instead you take a 40 foot drop before your last cam arrests your fall by sending your body directly into the face. Prusiks are more difficult to tie(and ascend!) when your hands are coated in your own blood, etc.
  - takk309 7y ago
    I have, thankfully, never had to try to tie a prusik with my hands covered in blood. If you had to do that, it sounds like a brutal fall.
  - planteen 7y ago
    Yeah for sure, injury changes things. You see rock climbers needing rescue often enough when they could have self-rescued by a pair of Prusiks and ascending the rope. I've heard of a rock climber using an ATC (rappel device) as an ascender, by kicking off the wall and moving the rope up a few inches. They were near complete exhaustion when they got up to the top - Prusiks would have made the job so much easier. Of course a pair of ascenders/Jumars is best, but add some weight. Most people (outside of cavers) don't plan on climbing up a rope with single rope technique, so it's not something that is practiced very much. I'm not really sure why. I'd be super nervous as a climber if I only could go one way on a rope. I guess alpinists practice it some for self-rescue out of a crevasse. Cavers use the rope as a nylon highway, so you know how to switch from rappel to climb, climb to rappel, and how to pick-off an injured party from the rope (all of those in space, where you can't take your weight off the rope at all).

Bartweiss 7y ago

It's always surprising to me how fall risks operate in the world of OSHA compared to rock climbing. There's an entire domain where people take good-sized falls as an everyday event, just sort of sitting in parallel with the domain where they're considered a major risk needing emergency-response measures. Obviously, some of that is a real difference in situation. Construction falls are unplanned and happen under all sorts of odd circumstances, and people are quite often injured during their falls. Climbers have someone managing the other end of their rope at all times, on a system that makes lowering them to the ground straightforward. But other differences seem absolutely pointless. The "suspended by your groin, legs hanging straight down" posture of construction harnesses massively accelerates suspension trauma, while climbing harnesses pull the legs up and keep pressure on large muscles. And there are companies starting to use that design for safety gear, so it's not a regulatory issue - it just somehow took decades to cross the gap.

takk309 7y ago
I big difference between a climbing harness and a construction harness is the tie in point. Climbing it is fine to have that point in front of the user. For construction, having the rope constantly in front of you would be a real inconvenience. By tying in on the back, the harness will hold the user in a different orientation just due to the way weight is distributed.
- Bartweiss 7y ago
  That's definitely part of it; climbing harnesses tend to support you in a position that's great for suspension trauma, but involves a pretty inconvenient rope. They're also waist-and-hip only, and while they'll reliably hold a climber through a flip, it doesn't sound great for chaotic, confined-space falls where you might stay upside down. The newer generation of construction harnesses are still back-clipped and full-body though - a short strap runs from the waist to the back clip to redistribute weight without normally being in front of you. Presumably getting that working smoothly and safely was an extra engineering hurdle, but I'm still surprised harnesses went so long without even including waistbands.
module0000 7y ago

burfog 7y ago

Falls from far less than that height can kill. If it is safe to be at 10 feet without that equipment, then it is safe to be at 1000 feet without that equipment. IMHO, the cutoff is just what the construction industry was willing to tolerate. The whole thing is a lobbyist battle between the construction industry and the safety equipment industry.

newmac 7y ago
I think that at a lower height, a rescue is considered to be easier. 10 ft would still require a safety program, it just wouldn't be fall arrest, more likely prevention (scaffolding)