Safety Harnesses and Tethers
<HTML><!-- eWebEditPro 126.96.36.199 --><P>Modern safety harnesses constructed of webbing and stainless steel have been so widely embraced by sailors that we run the risk of accepting all of them uncritically. While all harnesses are advances on the flimsy, homemade, rope contraption of yesteryear, it would be foolish to think that there are no important differences among them. Recently, some standards were identified in valuable tests of harnesses and tethers from 17 manufacturers that were conducted by the Sailing Foundation of Seattle, Washington. The foundation's report of its tests, released in late March, indicates that almost all safety harnesses provide the security that their names suggest - but, additionally, that almost half the harness tethers on the market may be flawed.</P><P><IMG height=135 alt="Doug Engle" src="http://www.sailnet.com/images/content/authors/rousmaniere/harness_1.gif" width=138 align=right border=0>This was an objective evaluation of gear purchased by the Foundation, the non-profit organization that developed the valuable Lifesling rescue device and has conducted tests of other safety gear. The harness and tether study was largely funded by another non-profit organization that concentrates on boating safety, the Bonnell Cove Foundation, which is the philanthropic arm of the Cruising Club of America. The study, conducted in late 1998, evaluated 21 harnesses and 17 tethers, almost all of them made for sailors (there were three rock-climber's or industrial harnesses). The boating gear, which of course is designed for the marine environment, received the most thorough testing and I'll summarize that gear's results here. There was a range of harnesses - many standard ones, some integral with inflatable PFDs, one built into foul weather gear, and several for non-boating use (such as rock-climbing). The tethers were 6-footers with hooks at the outer end and, in some cases, also at the body end.</P><P>Equipment that failed or had problems is identified in the text. At the end of the column is a <A href="http://www.sailnet.com/forums/showthread.php?threadid=20271" >list of the harnesses and tethers that passed</A> the tests.</P><P>The gear was put through three tests: in-water, land and dynamic loading. In the water, volunteers in harnesses were dragged astern from a boat at about 4 knots, as though they had slipped overboard while hooked on. This exercise tested comfort plus the wearers' ability both to reboard and to separate themselves from the boat if they believed they were at risk of drowning.</P><P>While all harnesses kept faces clear of the water at this modest speed, some funneled water into wearers' faces.<IMG height=119 alt="Elastic Tethers" src="http://www.sailnet.com/images/content/authors/rousmaniere/harness_2.gif" width=150 align=left border=0> None of the volunteer victims was able to climb back aboard unassisted. The quick-release snap shackles (like typical halyard and spinnaker sheet shackles), located at the tethers' body end, were easily opened to free victims. Everybody found the towing experience uncomfortable, but the degree varied. A person who wore a harness on top of a Type III (vest-type) life jacket complained of major back pain because the PFD kept the harness straps from sliding to their optimum location, under the armpits.</P><P>A land test evaluated wearer convenience and comfort, as well as harness construction. Volunteers needed 5 to 15 seconds to put on most harnesses, but more than 30 seconds were needed with some more complex devices. When volunteers were hoisted above the ground by the tether, discomfort again prevailed in varying degrees. A test for magnetism found only one harness that slightly affected compasses, the Jim Buoy model.</P><P>Women had an interesting take on the comfort issue. In both the towing and hoisting tests, members of the Tacoma (Washington) Women's Sailing Association found that for some women, some harnesses were extremely uncomfortable - even ones specifically designed for women. One woman preferred a high horizontal strap; another wanted a low one. Tastes varied with body shape.</P><P>Can your harness and tether take the shock load of a free fall across the deck or into the water? The Sailing Foundation attempted to answer this important question in a dynamic-loading test. A 220-pound dummy wearing a harness was dropped 6.6 feet. My engineer brother Arthur tells me that this drop would have a force of more than 2,200 pounds, assuming a little webbing stretch to absorb the shock load that might<IMG height=141 alt="Raudaschl Tether" src="http://www.sailnet.com/images/content/authors/rousmaniere/harness_3.gif" width=158 align=right border=0> otherwise fracture ribs and shatter fittings. Two harnesses failed this test: a webbing strap in the Jim Buoy harness parted, and webbing was shredded in the Stormy Seas foul-weather jacket with an integral harness. The cause in both cases appeared to be chafe from burrs and sharp edges on metal hardware. (A redesigned Stormy Seas jacket passed this test in late April.) The West Marine Basic and Securite harnesses passed the dynamic-loading test, but the report points out that both suffered some deformation in its single D-ring, where the tether attaches to the harness. Since another West Marine harness with two D-rings passed, this seems to be a design and not a structural problem.</P><P>The big shock in the report is that while almost all the harnesses survived, 8 of the 17 tethers failed the dynamic test "in such a way as to endanger the wearer," according to the report. Stitching came apart in three tethers: the Captain Al's Single Point and Three Point, and the Holland Yacht Equipment 1284T. Outer tether hooks were deformed or otherwise damaged in five: the Forespar Passagemaker, the Helly-Hansen K-947 Three Point, the Jim Buoy 922, the Raudaschl, and the Wichard 7001. The outer hooks that held up best had locking gates or similar mechanisms. Quick-release snap shackles (for the body end only, since they usually take two hands to open) also took the shock load without damage.</P><P>This is just a brief summary of the 50-page report, which describes the tests and results in detail. Here are some personal conclusions based on the report and my experience:</P><BLOCKQUOTE><LI>Buy a strong harness. Heavy webbing and two D-rings are mandatory. Finish must be smooth and hardware must be arranged so that there's no chafe on the webbing when the harness is strained. The tether must be heavily stitched and should have a gated hook at its outer end and a quick-release shackle on its body end. A combination harness/inflatable PFD is an excellent option. (If you buy an inflatable with an automatic-inflation system, frequently inspect and replace the inflation system.) Another option is a tether that includes some shock cord, which absorbs loads and keeps the gear from tangling in your feet (a Survival Technologies tether of this type passed the tests). <LI>Make absolutely sure the harness fits. Try it on with all the clothing you would wear and then stress it with some calisthenics. Women should be especially demanding about fit. <LI>While sailing, concentrate on using the harness both to keep you on board and to minimize loads on your body. Keep the tether short. A short tether means not only that you're unlikely to go over the rail but that there's less shock loading. When you're not moving around, hooked to a jackline (a line running fore and aft on deck), secure yourself to a fixed sturdy point that's to windward and away from the stern. A through-bolted padeye, cleat or winch will do. Many experienced sailors prefer a harness with two tethers, one shorter than the other, so they have this option and can also go forward and to leeward without unhooking. </LI></BLOCKQUOTE><P>This valuable study is available for $20, by check only, from the Sailing Foundation, P.O. Box 4213, Tumwater, WA 98501. Request the Harness and Tether Study (the foundation has also conducted studies of personal lights and anchors).</P><TABLE border=0><TBODY><TR><TD align=middle colSpan=3><FONT color=navy><B>BOATING EQUIPMENT THAT PASSED</B></FONT></TD></TR><TR><TD vAlign=top><FONT color=red><B>Combination harness-inflatables that passed</B></FONT> <LI>Captain Al's 1143 <LI>Mustang MD3012 <LI>SOSpenders 38MHAR-P <LI>Stearns 1143 <LI>Survival Technologies BO1330 <LI>West Marine (manual) </LI></TD><TD width=20> </TD><TD vAlign=top rowSpan=2><FONT color=red><B>Standard harnesses that passed</B></FONT> <LI>Captain Al's 1278T <LI>Forespar Passagemaker <LI>Gill Crewsaver <LI>Holland 1278T <LI>Lirakis Newport <LI>Musto 6652 <LI>Raudaschal <LI>Survival Technologies Deck Pro <LI>Survival Technologies Pelican 2 <LI>West Marine Basic (with deformed D-ring) <LI>West Marine Securite (with deformed D-ring) <LI>West Marine Ultimate </LI></TD></TR><TR><TD><FONT color=red><B>Tethers that passed</B></FONT> <LI>Lirakis Newport <LI>SOSpenders Three Point <LI>Survival Technologies with snap shackle <LI>Survival Technologies Shock Arrest <LI>West Marine with snap shackle< <LI>West Marine Basic <LI>West Marine with snap shackle and Gibb hook <LI>West Marine with dual snap shackles </LI></TD></TR></TBODY></TABLE></HTML>
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