Mailing List Archive Mailing List Archive
--=_ORCL_6586720_0_11919608160542460 Content-Transfer-Encoding:7bit Content-Type:text/plain; charset="US-ASCII" I am not sure exactly what depth compensation digital gauges do, which is why I posted the question to techdiver. I guess my real questions about oxygen tolerance and altitude are two: 1) How do real (analog/digital/computer) gauges compensate for altitude? I will probably check this out by doing a dive with a measured line. I may even read the instructions! I won't bother posting the answer to the list, because I have little doubt that the people who responded that this post is a troll are unlikely to ever do any serious high altitude diving. 2) Are there any other physiological factors which come into play for altitude diving which affect oxygen tolerance? I can't think of why this should be the case, but I'd hate to do a long deep dive and then find out the hard way on deco that there was some factor I failed to take into account. John ------------------------------------------------------------ John H. Heimann Sr. Product Manager Oracle Corporation Security Products 500 Oracle Pkwy, Box 659410 415-506-9750 (phone) Redwood Shores, CA 94065 415-506-7226 (fax) --=_ORCL_6586720_0_11919608160542460 Content-Type:message/rfc822 Date: 15 Aug 96 15:07:31 From:"Richard Pyle <deepreef@bi*.bi*.Ha*.Or*>" <deepreef@bi*.bi*.Ha*.Or*> To:JHEIMANN.US.ORACLE.COM,<JHEIMANN@us*.or*.co*> Subject:Re: High altitude decompression Cc:gmiiii@in*.co*,techdiver@terra.net In-Reply-To:<199608150449.VAA16401@ma*.us*.or*.co*> MIME-Version: 1.0 Content-Transfer-Encoding:7bit Content-Type:text/plain; charset="US-ASCII" > This is NOT true for at least some computers and digital gauges (e.g., the > Aladin Pro, and maybe also on the Uwatec digital depth gauge I normally use). > My understanding is that these sense the decrease in atmospheric pressure at > altitude and compensate for it, effectively resetting the pressure for depth = > 0 from 1 Bar to < 1 Bar. This means that the absolute pressure at an > indicated depth of 20 ffw is less than that at sea level. Are you sure about that? It seems to me that these computers should be taking a pre-dive ambient pressure reading so that they know what pressure to decompress the diver "to". I can't imagine they adjust the numbers that they read on the depth scale (= the numbers that they indicate as decompression ceilings) just to give the diver a better idea of the linear feet bewteen him.herself and the surface. Maybe they do - the only advantage would be that the computer wouldn't read "0" at 4 feet (or whatever 1 bar would be). But my understanding is that, because many divers use analog gauges, and therefore follow decompression stops according to ambient pressrues as it would be in saltwater at sea level, it would be dangerous for a computer to depart from that standard. Personally, I think we should all measure our depth in terms of atm or bar, rather feet or meters, because all of the physiological stuff is keyed to pressure, not linear feet from surface. Sorry is I added to any confusion. Aloha, Rich --=_ORCL_6586720_0_11919608160542460--
Navigate by Author:
[Previous]
[Next]
[Author Search Index]
Navigate by Subject:
[Previous]
[Next]
[Subject Search Index]
[Send Reply] [Send Message with New Topic]
[Search Selection] [Mailing List Home] [Home]