Biner on Biner

climber73 wrote:does anyone have test data on biner-to-biner connections? this doesn't seem all that much different from biner-to-bolt.

Since biners are pull tested between metal pins*, I think it's safe to say that the rated strength are indicative on biner-to-biner loading.

• I'm not sure the destructive testing is done this way, but I know OP tests every biner to a significant fraction of the rated strength; you can see the impressions left by the test pins. If UIAA biner testing is in fact between pins, then a more relevant question would be how they test when loaded by a sling.

I'm not aware of any biner-to-bolt hanger pull tests. But I'm no expert in the field of gear testing.

Gunkiemike wrote: Since biners are pull tested between metal pins*, I think it's safe to say that the rated strength are indicative on biner-to-biner loading. * I'm not sure the destructive testing is done this way, but I know OP tests every biner to a significant fraction of the rated strength; you can see the impressions left by the test pins. If UIAA biner testing is in fact between pins, then a more relevant question would be how they test when loaded by a sling. I'm not aware of any biner-to-bolt hanger pull tests. But I'm no expert in the field of gear testing.

Both karabiners and slings are tested between 10mm pins, there is no test for sling/karabiner, karabiner/bolt hanger etc since the standards are for individual pieces of equipment not combinations. Since the manufacturers have no control over how gear is combined this is the correct (and only workable)system.

The compatability between the various equipment types is set by the design standards (thickness, corner radii and so on) and is established by testing when the standards are written.

The manufacturers have a vested interest in their reputation and at the design stage will be testing for any incompatability that might occur in normal use but climbers are expected to be aware (and will be warned in the instructions) that using equipment outside the established system may be fatal, for example threading the rope direct through a plate hanger (in this case the system calls for a connector to be used).

There are thousands of tests of karabiners to bolt hangers performed every day anyway by falling climbers which is the other basis on which the standards are established, historic evidence. In other words experience tells us the standards for the two pieces of gear work together satifactorily.