Moderator: Tim White
snoboy wrote:I think you will see some more application of this (two prusiks on capture) as more teams adopt mirrored systems. Then it is not there because it's needed for capture, but it's there to make either line functional as a belay. There are actually some significant advantages to this ability to swap the roles of the ropes during the evolution.
As an aside, I believe NFPA does not certify, they just set standards. A provider may be able to teach a course that follows the NFPA rope standards, and is oriented to cave rescue.
snoboy wrote:NZcaver - I think you're on the right train of thought. The reasoning for two prusiks on the TTWPB is to distribute the heat and loading. If memory serves me correctly, a single TWP will catch a rescue fall, but it will glaze the prusik and the line possibly fusing them and making further progress difficult...
I think you will see some more application of this (two prusiks on capture) as more teams adopt mirrored systems. Then it is not there because it's needed for capture, but it's there to make either line functional as a belay. There are actually some significant advantages to this ability to swap the roles of the ropes during the evolution.
snoboy wrote:As an aside, I believe NFPA does not certify, they just set standards. A provider may be able to teach a course that follows the NFPA rope standards, and is oriented to cave rescue.
shibumi wrote:Jansen, I don't know the specifics of the folks you were talking with, but that misunderstanding seems to be VERY prevalent as every year we have people come into L2 wanting to do it that way when I know they weren't taught that at L1 and I know they didn't get training elsewhere. It only takes a few people to perpetuate that down before it starts becoming "standard" among some training organizations.
NZcaver wrote:shibumi wrote:Jansen, I don't know the specifics of the folks you were talking with, but that misunderstanding seems to be VERY prevalent as every year we have people come into L2 wanting to do it that way when I know they weren't taught that at L1 and I know they didn't get training elsewhere. It only takes a few people to perpetuate that down before it starts becoming "standard" among some training organizations.
Interesting. It's a mystery, Anmar. Perhaps some people are so enamored with the T3WP belay, they feel they must use a tandem set anywhere the system calls for a Prusik?
It was suggested that I might want to consult On Call to better understand the use of tandem Prusiks. Hmmm. I don't have my copy with me, but off the top of my head I can't recall it detailing the use of the T3WP for progress capture on the main line.
Stridergdm wrote:"On Call", you should be referencing the NCRC Manual of Cave Rescue Techniques
tagkycaver wrote:I was in a SAR training a few years ago where we performed drop tests/holding tests for sudden rescue loads; T3WP held every time (fused some though) whereas single knots and lots of other stuff frequently failed.
Stridergdm wrote:tagkycaver wrote:I was in a SAR training a few years ago where we performed drop tests/holding tests for sudden rescue loads; T3WP held every time (fused some though) whereas single knots and lots of other stuff frequently failed.
Agreed on capturing a fall, but that's not the point of a progress capture, which is what is being discussed here. (your mainline in theory should never be capturing a fall since it should normally be loaded.)
Return to Cave Rescue Techniques Forum
Users browsing this forum: No registered users