Firehouse.com Forum Rules & Guidelines

Forum Rules & Guidelines

Not Permitted or Tolerated:
• Advertising and/or links of commercial, for-profit websites, products, and/or services is not permitted. If you have a need to advertise on Firehouse.com please contact [email protected]
• Fighting/arguing
• Cyber-bullying
• Swearing
• Name-calling and/or personal attacks
• Spamming
• Typing in all CAPS
• “l33t speak” - Substituting characters for letters in an effort to represent a word or phrase. (example: M*****ive)
• Distribution of another person’s personal information, regardless of whether or not said information is public knowledge and whether or not an individual has permission to post said personal information
• Piracy advocation of any kind
• Racist, sexual, hate type defamatory, religious, political, or sexual commentary.
• Multiple forum accounts

Forum Posting Guidelines:

Posts must be on-topic, non-disruptive and relevant to the firefighting community. Post only in a mature and responsible way that contributes to the discussion at hand. Posting relevant information, helpful suggestions and/or constructive criticism is a great way to contribute to the community.

Post in the correct forum and have clear titles for your threads.

Please post in English or provide a translation.

There are moderators and admins who handle these forums with care, do not resort to self-help, instead please utilize the reporting option. Be mature and responsible for yourself and your posts. If you are offended by another member utilize the reporting option. All reported posts will be addressed and dealt with as deemed appropriate by Firehouse.com staff.

Firehouse.com Moderation Process:
Effective immediately, the following moderation process will take effect. User(s) whose posts are determined by Firehouse.com staff to be in violation of any of the rules above will EARN the following reprimand(s) in the moderation process:
1. An initial warning will be issued.
2. A Final Warning will be issued if a user is found to be in violation a second time.
3. A 3-day suspension will be issued if the user continues to break the forum rules.
4. A 45-day suspension will be issued if the user is found to be a habitual rule breaker.
5. Habitual rule breakers that have exhausted all of the above will receive a permanent life-time ban that will be strictly enforced. Reinstatement will not be allowed – there is no appeal process.

Subsequent accounts created in an effort to side-step the rules and moderation process are subject to automatic removal without notice. Firehouse.com reserves the right to expedite the reprimand process for any users as it is deemed necessary. Any user in the moderation process may be required to review and agree to by email the terms and conditions listed above before their account is re-instated (except for those that are banned).

Firehouse.com reserves the right to edit and/or remove any post or member, at any time, for any reason without notice. Firehouse.com also reserves the right to warn, suspend, and/or ban, any member, at any time, for any reason.

Firehouse.com values the active participation we have in our forums. Please ensure your posts are tasteful and tactful. Thank you very much for your cooperation.
See more
See less

Webbing strength confusion

  • Filter
  • Time
  • Show
Clear All
new posts

  • Webbing strength confusion

    Good morning everybody,
    During a my shift on a few days ago, we were training on anchors, 3:1 haul systems, and rigging a stokes. I had setup a W3P2 to anchor the safety line. In the middle of all this, one of our chiefs walked up and started asking “why does increasing the number of strands in the webbing make the webbing stronger?” He was convinced that a piece of webbing rated for 6,000lb is rated for 6,000lbs no matter how many times you wrap it or loop it or fold it. He held a straight piece in his hand and said “This is rated for 6,000lb.” Then he tied a water knot, held it up and said “And this is rated for twice as much now? Why?”

    So, I’m pretty new to this. Just got my FFI, I have 1 week of low angle rope rescue training. I have a LOT to learn, and while I have a comfortable understanding of this, I was unable to get him to that point.

    If I have that single loop of webbing, around a bollard, I understand that the load is distributed evenly (more or less) on each strand running back to the anchor. However, on the backside of the anchor, those two strands meet in one strand. Why does that one strand not get overloaded and fail?

    sorry for the book and the (likely) dumb question, but Chief asked me “Why?” And I’d like to learn the answer.

  • #2
    He's right.... sort of... I think.

    wrapping webbing does not increase it's strengths; the material itself still has the same breaking point at 6000 lbs.

    That being said, different configurations have different strengths, because of how the force is applied to the webbing, especially when discussing different methods of anchors. and if you have multiple strands going to multiple anchor points, you can distribute the load.

    check out https://www.cmcpro.com/one-inch-webbing-anchors-minimum-breaking-strength/ for some examples

    you can also check out http://www.mountaineeringlife.com/wp...strengths1.pdf

    Remember, knots affect the strength of the webbing, as do turns involving sharp angles.

    If my basic HazMat training has taught me nothing else, it's that if you see a glowing green monkey running away from something, follow that monkey!



    • #3
      While a W3,P2 has 4 strands sharing the load it theoretically has 4x6,000 lbs of load carrying capacity (thus 24k), assuming the webbing is rated at 6k on a single strand. I think it's typically closer to 4k though for 1". Even though the theoretical load is 24k, in practice and testing it will actually be closer to 13-14k before it breaks. This is due to friction, primarily between the strands where they cross over each other on the load caribeaner as the load increases.

      Like stated above, knots do affect strength, regardless of whether it's rope, webbing, chain, cable, whatever. Again, that's mostly due to friction. The reason you wrap 3, but pull 2 is to leave the knot on the back side of the anchor where the friction is isolated and the load does not affect the knot for the most part. It's the same reason you can do a "friction-less" hitch as an anchor.

      You would probably be well served to get the book "On Rope" by Padgett and Smith and do some reading if this is something that interests you.


      300x600 Ad Unit (In-View)


      Upper 300x250