Fellows, some times we have to use a ladder like an elevated anchor ponit for a raising system. We practiced last sunday in my station. What do you think about this type of system and what kind of recommendations do you have for this situation?
Looks like it works for you guys just like you intemded it to. Here are a few suggestions though. When you ae back tying the ladder, consider doubling up the webbing or using rope. The breaking strength of the webbing(4000 lbs) looks to be the weakest point of your system. If you were to use 1/2" rope (9000 lbs), you would have amuch higher safety factor. How are you tying off the ladd to prevent the foot end from kicking up and out? By the looks on everyone's faces, it looks like you guys are very secure in your system here. I also like the fact that you are using the ladder beams and not the rungs as your anchor points. Looks good.
Thank J, for your suggestion, we never think about the webbing like the weakness point of the anchor, your're right about using a rope; on the next practice we'll do it like that.
About your question we put the ladder base against a wall in order to avoid a movement, in the case that we don't have a wall (pry effect), we tied up the base.
Thanks Francis for your advise. We usually use only one rope, because we use the French school in rope rescue, but it's debatable. We'll consider to use a second rope for belay.
Fellows, something come to my mind, I was thinking about the breaking point of the ladder (we're using it like an anchor point and is important to know it).
Did you know exactly how much is it?
I wondering that using the beams is the safest option but we really can calculate the breaking point in order to know our safety factor?
THe ladder only becomes an issue when it is not used vertical the flatter the angle the higher the resultant force on the ladder. As you said earlier use the beams and the ladder at a steep angle, when rigging the haul system or the Mechanical Advantage tie the anchor 180 degee from the haul line with a double pulley at the top and single at the victim/rescue attachment. With this when you haul th resultant force will be directed towards the space. be safe Brother
I'm only saying 180 degrees from the anchor of the haul line so it puts the resultant force straight down from the overhead anchor, damn hard to explain let's all fly to Lima and build this a few times. And no we have never had a ladder fail even using the rungs and that is no a good idea. Like you said good discussion, I still say we just fly to Peru.
Another idea, when using the rope around the beams for you high anchor, instead of webbing, try a muli-loop bowline. If you are unfamiliar with this, I will attempt to explain it later. It is a great option when using less than perfect anchors to make one really good anchor point.
Our state fire academy used to teach a very similar system (ladder gin) but we no longer teach it because the ladders are not rated for anywhere near the forces that can be applied to it.
Aerial ladders are a different story - they can be used as an AHD as long as you know the rigging tricks and can keep the rigging factors within the tip rating of the ladder.
Lee, I know that you will be at Chile the next week for the CIFR, I'm also will be there. Let's talk about this thing; and maybe you can pass in a rush by Lima, (lol). Thanks for your answer.
Fran, thank for your advise, I'm appreciate your help.
Daniel, I will be in Santiago, Chile on the 18th for a few days then I will be in Concepcion and off to Valdivia for a Fire/Rescue Conference. If I have a few days I can fly up to Lima from Santiago....can't be sure at this point but if I can I will let you know....be safe brother