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This is a multi-part message in MIME format. ------=_NextPart_000_002E_01C03910.F0176960 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit GAS MIXING LESS THE BS: Let's assume all bottles are correctly marked - that means MOD only, horizontally, in three inch high letters , on either side of the upper bottle in the orientation of the tank. All tanks turned off, all regs parked. To deploy, we locate the bottle by MOD, we remove the reg and put it in our mouth, we then relocate the bottle by MOD, and turn if on. If we can breathe, we are breathing the right gas. Now, mixing. First put two pieces of tape or one GUE split tape on the empty bottle. Hook up to either gas, but I do helium first since I want my oxygen addition to be more in the middle of the operating range of the gauge, but it can be done either way. Figure the correct amount of helium for your mix considering coefficient of expansion and heat expansion. Helium will need about 17% overfill to get the % you seek. Let's say we want 50% and we are filling to 3000. Fill the tank first to 1750 to get to half, but then add another 10% or so for heat expansion, so go to a total of 1900 roughly. It should cool back to 1750 or so. No sense getting real anal here, the heat expansion is simply equal to the ratio of absolute temperature change, using the Kelvin scale - just guess at it. Turn the bottle off, but do not remove the whip until you have written down the contents of the tank and the date. Now remove the whip . Now, add the oxygen. Keep in mind that it will be heated and expanded, but not too badly. Go a little over your intended amount but not too much. Calculate this independently of the helium, and add it without regard for the "pressure" of the helium. If you added the oxygen fist, keep in mind that it will have expanded as well from the heat of the helium filling and be giving you a higher overall helium pressure reading than you really have, so add a touch there if that is the case over and above the other two reasons. Do not remove the whip until you have written down the new gas added and the date. Analyze it if you please, to solve for the helium later to satisfy yourself. Now add the air, unless that was heliox and we are done. Immediately analyze the gas and write the analysis on the other piece of tape or the split tape, write the date on it as well, and take the original tape off the tank and cover the valve with it to indicate that the tank is full. Do not move the tank until this is done. Obviously , the analysis should jive with the MOD. To dive the tank, you can remove the tape so as not to litter ( and obviously the only thing we go by in water by is MOD ) , but if you do not use the tank, retape it and the valve, rewrite the contents and date, and transport that way, including partially full tanks that you intend to reuse ( I reuse my deco tanks for two dives usually, so I may write some thigh like "2000 psi 50% 10-18-00") . If you use it and are not going to reuse it, it is now assumed that the tank has some amount of that gas in it, but can not be used again unless reanalyzed, so is not retagged. It can not be stored full without a tape, and it can not be transported full without a tape. Doubles can not be stored untagged if they have gas in them, and if that mistake is made, dump the partial gas and remix rather than adding to a mix. A lot of people fool themselves this way on the helium %. ------=_NextPart_000_002E_01C03910.F0176960 Content-Type: application/ms-tnef; name="winmail.dat" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename="winmail.dat" eJ8+IhsSAQaQCAAEAAAAAAABAAEAAQeQBgAIAAAA5AQAAAAAAADoAAEIgAcAGAAAAElQTS5NaWNy b3NvZnQgTWFpbC5Ob3RlADEIAQ2ABAACAAAAAgACAAEGgAMADgAAANAHCgASAA4AJQAAAAMAKQEB A5AGAOQLAAAiAAAACwACAAEAAAALACMAAAAAAAMAJgAAAAAACwApAAAAAAADADYAAAAAAB4AcAAB AAAAHgAAAEdhcyBNaXhpbmcgYW5kIEJvdHRsZSBNYXJraW5nAAAAAgFxAAEAAAAWAAAAAcA5MnWo tRlaD6T0EdSIeURFU1QAAAAAAgEdDAEAAAAVAAAAU01UUDpUUkVZQE5FVERPUi5DT00AAAAACwAB DgAAAABAAAYOAO6qZjI5wAECAQoOAQAAABgAAAAAAAAAS2YWq/4xwBGts/a3RGlr8sKAAAALAB8O AQAAAAIBCRABAAAA/AcAAPgHAACgDQAATFpGdYa1t80DAAoAcmNwZzEyNRYyAPgLYG4OEDAzM08B 9wKkA+MCAGNoCsBzsGV0MCAHEwKAfQqBknYIkHdrC4BkNAxg3mMAUAsDDDALtDgKogqEEGQgR0EF 8E1JWIBJTkcgTEVTBfCAVEhFIEJTOhPoVwqAFUARMCcEIGEEEHW7B4AXMGwDIAbgAkBsB5EvCsAX kAWhCXBjGCB5IAkAwHJrCYAgLSB0DxDwBUAHgAYiTU9EICMCIBkgLCBoBbBpev8CIRexGwELgBnR CdEcARDg+RsgaWcc0BgwAkAEkAQgYxsQAiAgZWkZ4ASQIDcAkAEAGsBmGdEXkHVwfnAeURf0HAQe sQiBG5F0jmkd4R7VAZBuay4RYNcXwSGyBCB0CHBuGZEe0O5mGxAXsglwZwQgCrEZgbEh8FRvIAEA C1BvGwH2dxeQCQBjGgAhkR8RH6W+YhkwGpElEwlwBGB2JbTvI7EXMBKAI/B1BUAeIBwC/whhGUAI YBngJRMeMQOgCXD/JW8mdygiIrIcAB7gAiAh8N5JHuAlMSpwA6BiCXAaAP8eQCUTGHItlAuAKAAn ox0BFQVAZxdALhYaTm93MRsQbWl4LvEh8EZppxEQBUAoYnR3JJBwCJD2YweRHtJhH2AgcRrBF5D0 R1UVwHMLUCihMyQgJB8nQAUwGTAX9CHwSG9vfmsfMRnQJJAeFS/RGxBifShxSSSgJJAeQDRAF3Ag vmYxswCQHLAXkDfQdwBwQxoRGTBveHlnKgFh3GRkHiAhAjahYheQBGC/GIEgFTEgOnAf4R7Vbx9h vyDhLwE9IA8gHrcv0HU6IP83dCihLVMXkDfwM7EeFTlw+nkxgmcIcCqkGLUXMClB7zmRHtE4JgWx eSkDMTAYof8AgQSBLvIFoAERDeAgoh7C/GV4CrAAgR3hKCIeQBoB/0WHNgE4NAPwF8Ei4BmRAaBh KVEgMTclGsAncHL/OJAiIiSQOiAyIR8RSPBDQe8ecAngIeEW5HNAgCUiOXP8NTBI8CgiLiVJUi7z JJD8MzBN4DGCIiIhhTiFNqH/SNBMMEmXOAEHQCNBN5Ip4/86YSgRGAAeQg9ASPEeYSSQb0MCRmwb EFKxZySQNqFh5zaRG6EewjE5TeAjoAhgnx0QGSAs0TjRGzB1bBSA/wWgBvAX4ADQNlBPdlKDIfD/ MNBKoQCAPkEdUT1TGkADIP8AcFUBHkEt8R8CRmwcAEtRxwdwC1AZMGVxdVUBNqH/J6Mg4h7CAaBS sApAKpI1Qd89EkDyEOE9sRsQdTjxLxT+SypAEiADoATwB0AXkBnA/mpfgC+xClAEERoBHiAkYX8s QirJIyM3kjfxUdEnKnd/HPA2gEIhAxFKchDwJ3F37wUQHWEDoDfwdyAkQ9FmYd50MtROlivzHxFk KoFYUv8H4GQ+MA9RcyBDOgMh8GAg/yTAHAIxIGiTYcNHxDshRmLvSEIoMUWDAQBkN3Rj8jag9zsB OmBWAkdUkjRBYvNJIb9DNAuAZmFvkUHmb+ptEsDqaCHwQwdAY1agKoRbsf8ScSTAcqICMBkhHtU4 JCvU/1GCbeMZ4EiSI7EUYkMCHwLcInAJcBdRCXAidlws0/9KcjphGZFsCDiBMdAbEBmA/2zvbfVl 029GFzElIRfBA1KfWnh2a00XKCI7IWdpYFH/KAB7QxzjHlFJEheyOCV5hv9ZcjqALwMDkUpyWYIZ IWXS/1QDUYM2kXRBHvI7ch7iYcL/IpFBQhdAcbV3UwbgJ3VR5N8yQi2hUrAAgCHwRGPfZO9/Zf4e 8yLgB+Av0Xt1aIxB+VnheXocgSiBeyQLUIux/1pSWIEG8CdxePY4JXTieRHzWIEg4XNmGTBDQhEg ULD3aq5rtwtwcl9hGuBhghnjfzlwBCA4IjnwTGo/sizRbf8HgDqAKoEZIVnSkbI+JBch/0yCZjEq pJtDAJAy0SAlHjP/MoMy6h8CNCglEZyXaQId0u8ooX91GxAr5GEZgCA2gqB/WeIzJAEgZ+wFoHHi HwJ2/wdAZfIeISiSNqEScQ3gKoTXGgFOh1uxZlagbIwXJ1efTsONpHU0BCCaJE9iEiC9CGBzGSFa ZJ0nVnVqgrD/piUfAhqRJGStkiF2GxBKcv8tUic5MyOHQgQgcCRxUx5R+igoE2+rlyBDGuF1Ii8B /yUxVFEmgRwROXCUsrTiGnT+KR2xPtN7JGPFX4CvGglw/zMjobJolaXjuGKciGc3KCJ/aQIr1T2R NCAJEZhmG+Nj/wpAhZMKsSDwhpOokiJGGfL/SnJydDaSCXC3orKQN9DApP85wQWCIkV48zJRruIE IF+A/1xxGvJSsTfQAMBLkZyTUrDXF4Eu0R0SaaLhIgHQVYEOcACQTCNSMS0xOC39TeAitkB697ei uPUYcoxi/1RQTWXApB4golEoorGSlxH/F1NtdU6HEPBLUcTyQfgZ4/+P8hwRyjI3ki1SjGI7Ibeh /0hRL9AcEZgFLaGRhG+xUrH3yrOMggGQZzogJFFWQc75/zHQO2F40b7SeAZUsaBDKCK/PxXPNbxH 0+8zE4wSdQJg3weR0v+NktJTiIRlhsTN9v8eMXcliJYxIDHQotJbsQDA+wEAGxBkF3A2gR8RviWb 9/8nMUOhPSGLI4XyOmJNdFSw/zEhIfElUUJDH2A88B/hAhD/VwHcApXhwyJ1M0BxNMY4JV4lIfAW GhPkEeEA5vALAAGACCAGAAAAAADAAAAAAAAARgAAAAADhQAAAAAAAAMAA4AIIAYAAAAAAMAAAAAA AABGAAAAABCFAAAAAAAAAwAHgAggBgAAAAAAwAAAAAAAAEYAAAAAUoUAAH1uAQAeAAmACCAGAAAA AADAAAAAAAAARgAAAABUhQAAAQAAAAQAAAA5LjAACwANgAggBgAAAAAAwAAAAAAAAEYAAAAAgoUA AAEAAAALADqACCAGAAAAAADAAAAAAAAARgAAAAAOhQAAAAAAAAMAPIAIIAYAAAAAAMAAAAAAAABG AAAAABGFAAAAAAAAAwA9gAggBgAAAAAAwAAAAAAAAEYAAAAAGIUAAAAAAAADAFqACCAGAAAAAADA AAAAAAAARgAAAAABhQAAAAAAAAsAdIAIIAYAAAAAAMAAAAAAAABGAAAAAAaFAAAAAAAAAgH4DwEA AAAQAAAAS2YWq/4xwBGts/a3RGlr8gIB+g8BAAAAEAAAAEtmFqv+McARrbP2t0Rpa/ICAfsPAQAA AJAAAAAAAAAAOKG7EAXlEBqhuwgAKypWwgAAUFNUUFJYLkRMTAAAAAAAAAAATklUQfm/uAEAqgA3 2W4AAABDOlxXSU5ET1dTXFByb2ZpbGVzXHRyZXlcTG9jYWwgU2V0dGluZ3NcQXBwbGljYXRpb24g RGF0YVxNaWNyb3NvZnRcT3V0bG9va1xvdXRsb29rLnBzdAADAP4PBQAAAAMADTT9NwAAAgF/AAEA AAAvAAAAPE1BQkJLTkxETE5OQkZDTUNKRk1ESUVHRkNBQUEudHJleUBuZXRkb3IuY29tPgAAAwAG EOLYbPkDAAcQLQoAAAMAEBAAAAAAAwAREAEAAAAeAAgQAQAAAGUAAABHQVNNSVhJTkdMRVNTVEhF QlM6TEVUU0FTU1VNRUFMTEJPVFRMRVNBUkVDT1JSRUNUTFlNQVJLRUQtVEhBVE1FQU5TTU9ET05M WSxIT1JJWk9OVEFMTFksSU5USFJFRUlOQ0hIAAAAAByo ------=_NextPart_000_002E_01C03910.F0176960-- -- Send mail for the `techdiver' mailing list to `techdiver@aquanaut.com'. 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