OTC 5261 Hydra V Hydrogen Experimental Dive to 450 Meters by C. Gortanand H.G.Delauze,Cornex Copyright 1986 Offshore Technology Conference This pager was gresented at the 18th Annual OTC in Houston, Texas, May 5-6, 1986. The material ia subject to correction by the author Permission to copy” is restricted to an abstract of not more than 300 words. -cl! HeliumhasWowed theprofessior!aldivertoworkon the continentsllshelfarea down to depthsof 300 HYDRAV wasprforrnedin03m MarseilleF@perteric meters.In thisrange,equipmentsndmethcdssrenow ResearchCenterin May and June 1985.Duringthis relativelywellestabliskl.Rbwever,in spiteof its experiment,6 diverslivedat a simulateddepthof450 remarkablequalities,heliumalonecannotb thevector meters in a hyperbaricatmosphere “composedof of oxygeninbreathiwgmixturesbeyonda certaindepth iT@wger],heliumandoxygen(I&dreliox). Indeed,deep diversmust cope with 2 limiting ‘lYsditionaldeepdivingwithheiiumis Iimitsdby 2 factors: factors: - ‘TheH@ PressureNervousSyndrome(Hpl@,linked - HighPreesureN&vous E@drome (HENS)thatcmEe3 to theeffectsof hydrostaticpressureon the motrici~disorderskeyond~ metere. centralnervoussystem.5ese WP inthe250 - Gasdensitythatiqairspihqary ventilation. / ~ meter rangeand increasewith depth, Hj@rogensimildextendtheselimitsthsnketo its causingmotordisturbancesthatmsy wsriously narcotic@ency thaths9sn sntagonkticeffectcn the imgs.irworkefficie~. HPNSsyndromesndthanksto itslightmolecularmass. The densityof breathingmixtures,which increasesprop%ionaUy to pressure,demandsa HYDRAV, firsthydrogenexperimentalsaturation aiasequentincr~ inbreathingefforts,which dive,wassuccessfully~rformed. hindersworkcapacity. Thefollowingcorxltermeasuremsyk propxsed: All the equipment and techniquesespecially - !Cheeffectsofpressurecanbe reducedby adding developedto use hydrogenhave proved entirely to the breathingmixturea givenamountof satisfactory. narcotic@s (heliumis not). Fromthebiomedicalstandpint,theimprovementwith - (%sdensitycanb reducsdby usinga vector- referencetoHelioxis outstand@ : thathasa lowermolecularmessthanhelium. - No HighPressureI’@vous.Syndrcme, Hjdrogenis theonlygas thatsatisfieskoththese - Emier br&thing. criteria.Becauseof theprogressin thesearchend exploitationof deepoffshoreoilfields,COMEXdecided TheverypromisingresultsofHYDRAV willho~~ to launcha newprogramfordeveloping~drcgendiving. lead to quick offshoreindustrialapplications. Ec&erimentshavebeencarriedout Eothat sea snd at ~drogenwill ensblediversto work in waterdepths itsresearchcenterinMarseille. rsr!gingfran403to 6C0meterwsndcertainlykeyond. - HydraIII- June1$&x divesat seaat depthsof 75 snd91 meters. - ~dra IV - November1983: chsmberdivesat INTRODUCTION deptk of 120,150,183,240and~ meters. - HydraV - MsysndJunel= : chambersduration For morethan20 yearsnow,sil deepcommercial divesat 450meters. diveshavebeencarriedout usingbreathingmixtures !Che~itive resultsof theseseriesof ~riments madeup essentiallyofheliumendowgen. leadw to envisiona rapidindustrializationof deep . Illustrationsat endof~pr. du~ OTC 5261 2 HYDRAV : HYIJROGENEXPERIMENT DIVETO 450METERS CHOICEOF AN ANTI-HPNSGASVBYKR breathingmixturecorn&osedof 21 oxygenand x$ hydrogen,the hydrcgenprtial pressurewas 18.6bar. Many@_@%aric experimentswereperformedto study At 240 me+&rs,the narcoticeffectwas evidentin HPNSsnd to establishvariousmethodsto reduceits alldivers.At thisdepth,withtheawnemixture,the effecks.A si@ ficantreductionin HIllSwas obtaind hydrcgenpartialpressureWSS24.5&r. by addingto theheliunwxygenmixturea givenamount At ~ meters,thediversbreathdH$ireliox. of nitrogen,thenarcoticpotencyof whichis well known. TwoE@drelioxmktureswereb?st~ti: -Mixturel : H,ydrcgen= 747 (pzirtialpr~e Unfortunately,the benefitof usingnitrogento 22.9tar’). reduceHPNSis hinderedby a significantdrawback: Hewmr = 247 increasein thebreathingmixturedensity,because @,ygen . 2$ nitrcgenisseven-timesheavierthanhelium. - mre 2 :H@rogen= 5% (p.rtislpreemre 18.3bar) IMringtheJANUSIV opration,thefirstdiveto 501 fkl.iunr. YPJ$ meters(worldrecord),carriedoutintheMediterranean (ky~wl} =2$ Seain IW7 byCXXIEX,aTTIHIIXgmmixturewasusedto pressurizethe chambers. The composition‘ofthe At thismaxim:ild,)lJli~we wantel II)evcnkrdly check mixturewasa~follows: the existenceof any rever:xil.or ruwcosison the - Oxygen = Iz premiseof an antagonistica~:tiotlof pressure: Nitrogen=574 “pressurereversaleffect”(SeeFigure1). – Helium = -94$ With mixture1 at 303 meters,thenarcosiswss thatresultsina densityof10.5~1. clearlylesssignificantthsnwithl~droxat240meters (p3rtialpressure.24.5 bar). ByusingHelioxattheeauedepth,thedensitywould Withmixture2 at‘~ metvrs,thesignsof narcosis haveken 8.2g/1,i.e.22$less. wereno lorgerdiscerniblewhereasthsywereat 183~ metersusingI&drox(p.rtialpre,wre= 18.6tar). We thereforesee thata largeamountof nitrogen cannotk usedwithouthinderingventilator-yfunction Thus,at 303meters,thehydrrmtaticpressureseems andreducingrespiratorycomfort. to be sufficientto exerta smallreveredeffecton hydrogennarcosis.However,thisphenomenonwas to & !l!heuse of hydrogeninstetiof nitrogenwas confirmedand this was a major objectivein the thereforedecidedupm, becauseit istwiceas lightas HYDRAV ex~riment. helium and becauseit is narcoticunder raised pressure,as provedby previousanimalexperiments carriedoutin *verallskoratories. omnms OF THEm v DIVJNIEXPm.mmr @ accountof thepw.itiveresultsof theHYDRAIV exprimentat ~ meters,HYll+AV w- designedat 450 meterswithtwocategoriesofobjethivesinmird: ‘l’henarcoticeffecto.faga~ speciesis directly 1. !Cechnical relatedto itsrpartialpressure.Hence,the narcotic . Definitionot hydroget~saturationdiving effecto.fn.ltrogenduringairdivingcccorsat tiut 50 procedures. metersintheaveragediverendthenrapidlyincresses, . Pr+industrkiL&kiorlof lifesupprt~~ms becomingdangerousbeyond70/75meters.Thepartial spcifictohydrogenatnros@eres. pressureof nitrogenat 50 metersis 4.7bar,and__6.’7 . Definitionof wfetye.luipnrentandprocedures. barat 7’5meters. 2. Physiological Studyof the:Yki-HPNSet’.feckoflydrogsn. In order to quantifythe narcotic~teilcyof Verificationof thepresswrereveredeffed. hydrogenin marl,LXIMl{lXcarricxioutin Novemberl= a ‘toxicological:;hldyoL’thecrli?ckson man of worldpremiere@x@riluexti.___kmin&thisexperiment,6 longexp.xuresto l@l partialpressuresof Heliox-saturateddivers (3 professional and.3 hydrogen. scientific)breathed ‘~Hydrox”(H2‘and 02) and Controlof isob~~riccounlx+r-diCtusionupon ‘T?ydrelioi’(H2,Me,02)miituresforseveralho~. at transferFronla hydrogetlatmosphereto a depthsof 120,150,!EO,240and~ met%rs. heliumatmosp+wre. Studyof theventiktoryfunctionat restand At IE13meters,distinctivenarcosissigm were duringmuscularexercise,kothmlderdryand otservedin someof thedivers.At thisdepth,witha. wet conditio!w. OTC 5261 ‘&)RTAN& DELAUZE 3 mm.umiw SEP-UP —— Thehyprbaricfacilities“oT‘%-eCOm ~rirnentsl. Theflammabilitylimitsof hydrogenat atmospheric Centerwere arrangedto obtaintwo distinctzones pressurearethefollowirg: (Figure2). IOwlimit ! Highlimit 1. I#zirelioxzone In air 4$ ! 74.5$ In oxygen 474 ! 94% The Hydreliox zone was made up of 3 interconnecteds@ericeldivingchanters,with Priorto theHYDRAIVex&riment, we determined specificarrangementsfor hydrogenuse. !Che flammebili~limitsof (H2,~, 02)ternarymixtures systemcouldaccomrxiate3 ‘setiateddivers. underpressure. Resultscanbe summarizedas follows: - S@ere 1 :Living chariber,equippedwith3 1. Hydrelioxmixturesare non flammablewhen the bunks. oxygenfractionalconcentrationis lowerthen 4.4~Mtil atota pressureof 76 bar, i.e.a - Sphere2 : %iiitaryti”lxrelsoequivalentto pressureequivalentto a depthof 750 meters a divirgbellon topof the wet (me 3). pt. It can thereforebe statedthatthereis no longera riskof fireina~rbaric chanberas - Sphere3 :Laboratorysnd work chamber soonss theoxygenconcentrationis lowerthen underdry conditions,or wet pot 4.4$,correspondingtothe followingpartial. forunderwaterstudies. pressuresas a functionof depth: 102(mbar)! Depth(meters) P@iolqgicalcomfortwesriaintainedbymeaneof ! a new lifesuppx%system,~cidly develo@ 403 ! 81 forHydrelioxatrnos~eres. m! 114 m! 126 Thisequip%entensured_: To havea wide stietymargin,we decidedto inject@drogenintothechambersonlyfrcmX0 - thermo+ygrcmetriccontrol, meters,where,foran oxygenpressureof 4.cO - theeliminationof carlmndioxide end cxiours, mbar,theoxygenfractionalconcentrationis – the centinuouere-oxygenationof the gas lowerthan2% mixtureto compensatethe divers’oxygen 2. Furthermore,thisl&rirelioxmixtureinflammable consumption,and its eliminationduring ody with a hydrogenfractionalconcentration decompression. higher* 7.5foratotel pressureof 10 bar (m 4). mi~ decompre=ion,hydrogenis 2. Helioxzom selectivelyeliminatedto ensurea concentration lowerthan4%whenreaching2CDmeters. A high capacitycylindrical.chsmber with transferlock, able to accommodateup to 8 It csnthereforebe statedthatthe fireriskis persons(6divers+ 1 doctorwithhisassistant, elmost non-existentat great depth in hydrogen if requiredin a Helioxatmosphere).This atms@eres. chamber was connectedto Sphere 2 of the On the other hand, the fire risk outsidethe Hj-drelioxzone.‘Itprovidda retreatpition chzukers,eventuaUyiniucedby leak mustlx?seriously intheeventofenemergencyend&hermore w tekenintocmsideration. intendedfor the finaldecompressionof the All gps circuithosepip werereplacedby rigid divers. StSinkxrsteelor cop~r pi- Thechenkersof tie W%=~ne werecover~~a h~comect=d outdoors It was amnectedto a eonwntionsllifewpprt throughahighflow cqaci~gxexhamt system.Aset systemformaintainingcomfortable@ysiologiczil of hydrogen