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I was asked to forward this to the list as the writer is having server problems. >X-Mozilla-Status2: 00000000 >Message-ID: <37AD8D70.AC5F9DA5@be*.ne*> >Date: Sun, 08 Aug 1999 14:00:17 +0000 >From: bigvon@be*.ne* >X-Mailer: Mozilla 4.51 [en]C-bls40 (Win98; U) >X-Accept-Language: en >MIME-Version: 1.0 >To: kirvine@sa*.ne* >CC: techdiver@aquanaut.com >Subject: Modified DIR-Ocean >References: <012f01bedf5a$60784ce0$6c64a8c0@dr*.is*.ne*> <3780F3A0.6290@sa*.ne*> >Content-Type: multipart/alternative; > boundary="------------8752297CC18478DAC4751B7F" > >George >Here is a brief summary in answer to your posted question. I have heard all the >pro's and con's to each of the modification I have made. I have found in 27 years >of diving in the ocean and as a maritime attorney and observing accident reports, >experts on the stand, commercial diving contractors, etc., these modifications >work. > >The following parameters apply for the Modified DIR : > >Open Ocean - Decent visibility - No overhead penetration - No scooter > >Most dives in the ocean are from a vessel. > >The visibility off shore is usually very good. There is no need for a canister >light. >Obviously in a limited vis or no light situation one would need his canister >light. (East Coast). > >If penetration were involved then it would be treated as an overhead/cave dive and >DIR would be appropriate. I doubt that the majority of ocean dives involve >penetration. > >I also assert that the majority of ocean divers do not have Gavins and further >that most dives are free swimming dives without a scooter. (Gas supply related) > > >Modified Equipment: > >5' hose. >All you need since no canister light, and a longer hose can become dislodged at >the worst possible moment, (in wave surge upon entry or exit, or swimming among >snags on bottom) No need to swim single file so the 5' is perfect in the >minimalist philosophy. > >Redundant bottom timer or computer. >This has been beaten to death. BUT if for ANY reason, unintentionally, >intentionally, act of god, environment, current, visibility, heart attack, etc. a >diver becomes separated from his buddy (yes he violated DIR rule#2) and has a >substantial decompression obligation, he better have a backup way to tell time, >depth and schedule. (BT/Tables or computer). > >Lights >As stated before a canister light is usually unneeded on ocean dive. AS such, no >NEED for primary and multiple secondary backup lights. (Bring one if you want to >as a tool.) > >Lift Bag and real Reel >The purpose of a lift bag is obvious. I also advocate for the ocean, a reel with >heavier line than cave line knotted every 10 or 20 feet. Cave line will cut too >easily on a wreck's sharp edges. Knots might serve to tell distance on a dive or >in an emergency deco situation. > > >Surface Signal >Since the ocean can change so quickly one must be prepared in the event he is >swept away past the boat or surfaces away from the vessel. The easiest is to use >the lift bag (provided it is a bright contrasting color) as a signal. I also bring >a signaling mirror which I have seen save the day. A whistle also helped locate >three divers who were swept off the Monitor in 1995. These items are relatively >small yet provide a huge safety margin. > >Steel tanks >Let me say right off the bat that while I understand DIR uses aluminum tanks (and >a weight belt), that is just not sufficient gas for a swimming deep gas dive with >a sufficient reserve. Maybe a 10 or 15 minute bounce dive, but our bottom times >are routinely 20 to 30 minutes at 200 to 350'. A scooter could change this but >most are not scootering. >Double steel with aluminum back plate (light) and aluminum stages are needed. >With this weight comes the need for redundant lift. (Here comes the flames) >Two separate Halcyon or Diverite wings with a wet suit, or only one with a dry >suit. > >Decompression stress >In order to provide the maximum safety margin while using high ppo2 deco mixes >(with breaks of course) and to ease diver exertion on deco a Jon Line is >essential. >The best option, if available, would be to arrange a free floating deco line >before hand. But if this is not available a Jon Line is an efficient tool. > >Spare Mask >Since the ocean has no floor or ceiling like a cave, a spare mask is essential. > > >Flame away fella's!!! > >Bill > >PS. I would be interested in hearing from any other ocean divers who have any >suggestions, as there is always room for improvement. ><!doctype html public "-//w3c//dtd html 4.0 transitional//en"> ><html> >George ><br>Here is a brief summary in answer to your posted question. I have heard >all the pro's and con's to each of the modification I have made. I have >found in 27 years of diving in the ocean and as a maritime attorney >and observing accident reports, experts on the stand, commercial diving >contractors, etc., these modifications work. ><p><u>The following parameters apply for the Modified DIR</u> : ><p>Open Ocean - Decent visibility - No overhead penetration >- No scooter ><p>Most dives in the ocean are from a vessel. ><p>The visibility off shore is usually very good. There is no need for >a canister light. ><br>Obviously in a limited vis or no light situation one would need his >canister light. (East Coast). ><p>If penetration were involved then it would be treated as an overhead/cave >dive and DIR would be appropriate. I doubt that the majority of ocean dives >involve penetration. ><p>I also assert that the majority of ocean divers do not have Gavins and >further that most dives are free swimming dives without a scooter. (Gas >supply related) ><br> ><p><b>Modified Equipment:</b> ><p><b>5' hose.</b> ><br>All you need since no canister light, and a longer hose can become >dislodged at the worst possible moment, (in wave surge upon entry or exit, >or swimming among snags on bottom) No need to swim single file so the 5' >is perfect in the minimalist philosophy. ><p><b>Redundant bottom timer or computer.</b> ><br>This has been beaten to death. BUT if for ANY reason, unintentionally, >intentionally, act of god, environment, current, visibility, heart attack, >etc. a diver becomes separated from his buddy (yes he violated DIR rule#2) >and has a substantial decompression obligation, he better have a backup >way to tell time, depth and schedule. (BT/Tables or computer). ><p><b>Lights</b> ><br>As stated before a canister light is usually unneeded on ocean dive. >AS such, no NEED for primary and multiple secondary backup lights. (Bring >one if you want to as a tool.) ><p><b>Lift Bag and real Reel</b> ><br>The purpose of a lift bag is obvious. I also advocate for the >ocean, a reel with heavier line than cave line knotted every 10 or 20 feet. >Cave line will cut too easily on a wreck's sharp edges. Knots might serve >to tell distance on a dive or in an emergency deco situation. ><br> ><p><b>Surface Signal</b> ><br>Since the ocean can change so quickly one must be prepared in the event >he is swept away past the boat or surfaces away from the vessel. >The easiest is to use the lift bag (provided it is a bright contrasting >color) as a signal. I also bring a signaling mirror which I have seen save >the day. A whistle also helped locate three divers who were swept off the >Monitor in 1995. These items are relatively small yet provide a huge safety >margin. ><p><b>Steel tanks</b> ><br>Let me say right off the bat that while I understand DIR uses aluminum >tanks (and a weight belt), that is just not sufficient gas for a swimming >deep gas dive with a <i>sufficient reserve.</i> Maybe a 10 or 15 minute >bounce dive, but our bottom times are routinely 20 to 30 minutes at 200 >to 350'. A scooter could change this but most are not scootering. ><br>Double steel with aluminum back plate (light) and aluminum stages are >needed. ><br>With this weight comes the need for redundant lift. (Here comes the >flames) ><br>Two separate Halcyon or Diverite wings with a wet suit, or only one >with a dry suit. ><p><b>Decompression stress</b> ><br>In order to provide the maximum safety margin while using high ppo2 >deco mixes (with breaks of course) and to ease diver exertion on deco a >Jon Line is essential. ><br>The best option, if available, would be to arrange a free floating >deco line before hand. But if this is not available a Jon Line is an efficient >tool. ><p><b>Spare Mask</b> ><br>Since the ocean has no floor or ceiling like a cave, a spare mask is >essential. ><br> ><p>Flame away fella's!!! ><p>Bill ><p>PS. I would be interested in hearing from any other ocean divers >who have any suggestions, as there is always room for improvement.</html> > -- Send mail for the `techdiver' mailing list to `techdiver@aquanaut.com'. Send subscribe/unsubscribe requests to `techdiver-request@aquanaut.com'.
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