US SAILING - Safety At Sea - Safety Studies - 1999 Harness and Tether Study - Appendix I

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Safety At Sea - Harness and Tether Study - Appendix I Part 3

Appendix I
Summary of Product Data
Tethers

General Comments on the tethers:

The build quality of the tethers varied considerably from company to company. Some tethers failed in the sewing, and some failed at the hardware. We generally consider a tether with a quick release shackle at the inboard end to be an important feature; however, we tried to test as broad a spectrum of hardware as possible, to see if there might be any lessons to be learned. As with the harnesses, we will leave it to the reader to determine whether they consider something like a quick release shackle with a bent pin to be a failure, even though the shackle didn’t open and let the dummy free. However we do consider it a failure when a gated snap hook fails in such a way that the gate remains open. We were somewhat surprised that there were as many tether failures as we found. It appears that the weak link in the whole system generally comes down to the tether.

Captain Al’s Single Point Tether


Captain Al's Three-point (left) and Single (right) tethers

This is a 6 foot tether with two locking aluminum carabiners, rated at 2000 kgs (4400 pounds) on the ends. This tether has a very short amount (less than one inch long) of stitching holding the carabiners in place. Also, the stitching is black on a dark blue webbing, making it hard to inspect without very good lighting. When wearing a tether without a quick release, the crew should always have a knife within easy reach in case they get trapped and need to release themselves. When subjected to the dynamic load test, the stitching parted, allowing the test dummy to come free.

Recommendation: We cannot recommend this tether.

Captain Al’s Three Point Tether


Photo showing the failed stitching of Captain Al's Single and Three-point tethers

This is a three-point tether with one leg of approximately three feet and one leg approximately six. The outboard ends are anchored by two of the same locking aluminum carabiners that are used on the single point tether, while the inboard end has a quick release shackle. Again, this unit had very short, black stitching holding the hardware in place. When subjected to the dynamic load test, the stitching parted, allowing the test dummy to come free.

Recommendation: We cannot recommend this tether.

Forespar Passagemaker Tether

Photo showing the failed snap hook on the Forespar Passagemaker tether. The shape before the dynamic load test can be seen in the photo of the Passagemaker Harness.

This is an approximately five and a half foot tether with a small locking hook on the outboard end, and a snap ring on the inboard end. There is a small button on the locking hook used to unlock the gate, which is an improvement over the standard snap ring without a locking gate. We found the button to be somewhat difficult to actuate, because it was small. The stitching is done in yellow on yellow webbing, making the inspection of stitching very difficult even in good light. When wearing a tether without a quick release, the crew should always have a knife within easy reach in case they get trapped and need to release themselves. When subjected to the dynamic load test, the inboard snap ring bent straight, allowing the test dummy to come free.

Recommendation: We cannot recommend this tether.

Holland Yacht Equipment Single Tether

This is a 6 foot tether with two locking stainless steel snap hooks, rated at 2200 kgs (4800 pounds) on the ends. This tether has a very short amount (about 1-3/8 inch long) of stitching holding the snap hooks in place. Also, the stitching is black on dark blue webbing, making it hard to inspect without very good lighting. Due to an ordering error we had two tethers. When wearing a tether without a quick release, the crew should always have a knife within easy reach in case they get trapped and need to release themselves. When subjected to the dynamic load test, on the first tether the stitching parted, allowing the test dummy to come free. When the second tether was tested the stitching at both ends gave way, allowing the test dummy to come free.

Recommendation: We cannot recommend this tether.

Helly Hansen Three Point Tether Model K-947

This is a 6 foot, three point tether of somewhat unusual design. Instead of having one leg of three feet sewn into another leg of six feet (which is fairly common in the industry), this tether has a loop sewn into its middle to attach the second snap hook. There are three identical snap hooks. The stitching is yellow on yellow webbing, making it hard to inspect without very good lighting. When wearing a tether without a quick release, the crew should always have a knife within easy reach in case they get trapped and need to release themselves. When subjected to the dynamic load test, the stitching parted where the intermediate (3 foot) snap hook was attached, although the webbing kept its integrity and the test dummy didn’t come free. However, one of the snap hook gates bent open, which might allow the tether to come unhooked. We consider this type of defect to be a failure.

Photo showing failed snap hook and torn webbing of the Helly-Hansen tether

Recommendation: We cannot recommend this tether.

Jim Buoy 922 Tether
This is a six foot rope tether with a single gated snap hook on one end and spliced loop at the other. This tether comes as a package with the Jim Buoy harness. It is attached to the harness by snaking the hook end through the D-rings and the loop at the end of the tether, making a "permanent" attachment at the inboard end. The locking gate used for this product was the only one to fail the ORC requirement of being able to pass a 0.500" dowel through its opening. The splice is apparently well done and the white whipping on a gold and white rope sheath is not too bad for inspection. When subjected to the dynamic load test, this tether had no failures.

Recommendation: This tether will work, although we think the harness that comes with it could be potentially life threatening. When wearing a tether without a quick release, the crew should always have a knife within easy reach in case they get trapped and need to release themselves.

Lirakis Newport Tether
This is a six-foot tether with a single forged Wichard snap hook on one end and loop in the webbing at the other. This tether comes as a package with the Newport harness. It is attached to the harness by snaking the hook end through the D-rings and the loop at the end of the tether, making a "permanent" attachment at the inboard end. The stitching is white on red webbing for good contrast, however the stitching is spaced somewhat far apart making inspection a little tougher than it could be. When subjected to the dynamic load test, this tether had no failures.

Recommendation: This is a good basic tether. When wearing a tether without a quick release, the crew should always have a knife within easy reach in case they get trapped and need to release themselves.

Raudaschl Tether

Photo of hardware failure in the Raudaschl Tether. Top photo - before the test, bottom photo - after the test.

This is a six foot tether with what appear to be cast snap rings on the ends. The stitching is a black or dark blue on a medium blue webbing, making inspection difficult. When wearing a tether without a quick release, the crew should always have a knife within easy reach in case they get trapped and need to release themselves. When subjected to the dynamic load test, the snap ring deformed from a "D" shape to a straight "I" shape, allowing the test dummy to come free.

Recommendation: We cannot recommend this tether.

SOSpenders Three Point tether with Snap Shackle

This is a three point tether with one leg of approximately three feet and one leg approximately six. The outboard ends are anchored by two of the same type of gated snap hook, while the inboard end has a quick release shackle. The stitching is white on medium blue webbing, making inspection relatively easy. When subjected to the dynamic load test, this tether had no failures.

Recommendation: This is a good tether, which allows crew the freedom of either a long or short tether length. We would prefer to see either the Wichard or Gibb locking gated snap hook on the outboard ends.

Survival Technologies 6’ Tether with snap shackle

Survival Technologies Single tether (left) and Shock Arrest tether (right).

This is a six foot tether with a gated hook/carabiner on one end and a snap shackle on the other. The locking gate is easy to actuate with one hand. The stitching is red on black webbing, making inspection relatively easy. When subjected to the dynamic load test the pin on the snap shackle bent slightly, although if the release cord was tugged, the shackle would release. The test dummy did not come free even with the bent pin.

Recommendation: This is a good basic tether.

Survival Technologies Shock Arrest Tether

This is a six foot tether of unusual design. Instead of using webbing, it uses a spliced braided line. Woven into or around one end of the line is a piece of shock cord to help absorb the load of a fall. One end has a snap shackle and the other a snap hook. The splicing appears good, but the whipping is black on a black sheath so inspection requires good eyes and good light. When subjected to the dynamic load test there were no failures.

Recommendation: This is a good tether of interesting design to help absorb shock loads.

West Marine 6’ Tether with snap shackle

This is a six foot tether with a gated hook/carabiner on one end and a snap shackle on the other. The locking gate is easy to actuate with one hand. The stitching is white on medium blue webbing, making inspection relatively easy. When subjected to the dynamic load test, this tether had no failures.

Recommendation: This is a good basic tether.

West Marine 6’ Basic Tether

This is a six foot tether with a snap hook on each end. The locking gate is easy to actuate with one hand. The stitching is white on medium blue webbing, making inspection relatively easy. When subjected to the dynamic load test, this tether had no failures.

Recommendation: This is a good basic tether. When wearing a tether without a quick release, the crew should always have a knife within easy reach in case they get trapped and need to release themselves.

West Marine 6’ Tether with snap shackle and Gibb Hook

This is a six foot tether with a locking Gibb snap hook on one end and a snap shackle on the other. The locking gate is easy to actuate with one hand, and doesn’t suffer from the ability to open when twisted around a padeye (the single wire sprung snap hooks will open when twisted around a padeye in a not too unusual manner, causing them to open inadvertently). The stitching is white on medium blue webbing, making inspection relatively easy. When subjected to the dynamic load test, this tether had no failures. We used 25 of this model for our harness testing, and none of them failed.

Recommendation: This is a good basic tether.

West Marine 6’ Tether with dual snap shackles

This is a six foot tether with a snap shackle on both ends. The stitching is white on medium blue webbing, making inspection relatively easy. When subjected to the dynamic load test, one of the pins on the snap shackle bent slightly, although if the release cord was tugged, the shackle would release. The test dummy did not come free even with the bent pin.

Recommendation: There is a good basic tether. However since it is sometimes necessary to use two hands to secure the snap shackle, we don’t recommend the use of snap shackles on the boat end of the tether.

Wichard 7015 Tether

This is a six foot tether with a patented locking gate hook on the ends. The locking gate is easy to actuate with one hand. The stitching is multicolored on medium blue webbing, making inspection relatively easy. When subjected to the dynamic load test, this tether had no failures.

Recommendation: This is a good tether, although it does not have a quick release shackle on the end. When wearing a tether without a quick release, the crew should always have a knife within easy reach in case they get trapped and need to release themselves.

Wichard 7001 Tether

This is a six foot tether with forged snap rings on the ends. The stitching is multicolored on medium blue webbing, making inspection relatively easy. When wearing a tether without a quick release, the crew should always have a knife within easy reach in case they get trapped and need to release themselves. When subjected to the dynamic load test, one of the gates on a snap ring came unsprung. While the test dummy did not come free, we consider this type of defect to be a failure.

Recommendation: We do not recommend this tether.

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