pfeiffer@uwvax.UUCP (Phil Pfeiffer) (07/28/85)
I received the following reply to my net article on Casio watches from Boston University: > I Scuba dive and I would NEVER EVER buy a watch not water resistant to 200M > That watch is your life. I would be risking my life to buy a 50M watch > and expect to go to any depth. You deserve to have a broken 50M watch. I > don't know what the big deal is anyhow. My Casio 200M was only $40 and > is now running for 2 years perfectly. The watch has stayed running longest > out of the LCD's that I have owned. Besides, what do you expect for > a watch that is <$50 these days. When diving it is always better to be safe > then sorry. The author posted the reply to me directly, but I thought it merited public comment. First: I agree completely with the author's main point: false economies are a bad diving policy. You risk your health and life when you buy substandard diving equipment in order to save money. We do try to be safety-conscious about what we buy; I apologize for not saying this in in my first posting !! We goofed when it came to the Casio's. We failed to read the fine print in the owner's manual explaining that "water resistant to 50M/100M" didn't mean "water resistant to 50M/100M" when it came to diving. My gripe was that I thought the statement about the watch being water-resistant was misleading; why else would you pay extra for such a watch if you didn't want to use it underwater?? Since both watches worked well down to 50' (15M), we were really surprised when the 50M watch gave up the ghost 48 hours after the dive to 82' (24M). I posted the first article as a warning. However, I disagree with the author, if he's suggesting that dive watches need to be rated to 200M to be safe. According to the U.S. Navy, standard compressed air scuba can only be used safely to 150' (45M). The major U.S. training agencies (e.g., PADI, NAUI, YMCA) treat this as a theoretical limit, encouraging divers to stay well above 150' (and, parenthetically, urge divers to take extra training if they wish to plan dives below 60' (18M)). Why, then, do I need a watch rated to 200M if I'm not a commercial or a professional diver? Postscript: Linda has a combination depth-gauge / automatic bottom timer on order now; I'm going to stop diving with my Casio and buy a bottom timer instead. If we wanted an even greater margin of safety, of course, we should think about buying one of the new generation of decompression meters (e.g., the Edge or the Deco-Brain (cf. the articles on multi-level diving and the reliability of the decompression tables in the last two issues of _Underwater USA_). These meters still cost $600 and up !!!, but I can see the day coming when NOT diving with a decompression meter will be also viewed as a false economy. [BTW, anyone else on the net have any experience with the new generation decompression meters?] -- -- Phil Pfeiffer "Call all hands to man the capstan/ See the cable running clear/ Heave away, and with a will, boys/ For New England we will steer." [Ed Trickett]
bsisrs@rruxe.UUCP (R. Schiraldi) (07/29/85)
First my qualifications: A PADI Divemaster for two years and a sport diver for more then ten years. Second on the subject of watches, I had one of those casio "watches", and had only one problem with it after two and a half years (one half the life span of the watch's battery), the watch shorted out after spilling a beer (a Weiss beer from Munich) on it. The watch was WATER resistant to 200M but note that does not mean PRESSURE resistant. I had the watch down to (backed up with a Princeton Tech Bottom Timer) 110' with no problems. I have since replaced the watch with a Heuer watch PRESSURE resistant to 20 ATM (that is 660 feet salt water). > ... but I can see the day coming when NOT diving with a decompression > meter will be also viewed as a false economy. Third, WHAT ARE YOU, NUTS OR SOME THING!?!?!?! Sorry, but if you are planing to get a decompression meter, save your money for the chamber ride you WILL need if you rely on that trash. Read these TRUE horror stories about them. I was on a wreck at 90' when someone else on the boat found one of these meters with barniculs (sp?) on it and it still read NO DECOMPRESSION STOP REQUIRED!! Another incident occured about a year ago, a diver desided to buy a meter and used it on a 145' dive. His bottom time was 15 minutes and the meter said no stop required. He stayed on the surface for 45 minutes and the meter said he could dive to the same depth for 15 minutes, only he stayed down for 12 minutes to be safe. The guage also said no stop was required but he did stop at 10' for 10 minutes. Unfortunatey, after a 5 minute hang, he doubled over and lost consiousness. He was brought aboard the boat, and after MUCH delay, was brought to a chamber about NINE HOURS after his intial hit. Today, he has very little control over his bodily functions and has to be reminded who he is. I can give other stories about wasting $600 to $800 on a meter, but the best thing I can say is spend the money on a GOOD watch and depth guage and learn to use the tables properly and know you own limitations. Dive safe!! Rich Schiraldi (21546) No disclaimer needed for my own opinions and the truth.
pfeiffer@uwvax.UUCP (Phil Pfeiffer) (08/02/85)
> > ... but I can see the day coming when NOT diving with a decompression > > meter will be also viewed as a false economy. > > Third, WHAT ARE YOU, NUTS OR SOME THING!?!?!?! > Sorry, but if you are planing to get a decompression meter, save your > money for the chamber ride you WILL need if you rely on that trash. > Read these TRUE horror stories about them. ( ... ) ... (the stories are horrible, but lengthy, so I won't reprint them here ) Muchas gracias, Rich, for the followup, and for your comments. If we continue to get this sort of cross-talk on the net, we may yet save net.rec.scuba. Re decompression meters: If you reread my followup, you'll notice my reference to "second generation" decompression meters and an article in _Underwater USA_. I'm sorry if that didn't explain what I meant well enough. Let's try again. The 1st generation meters, as you indicate, were *bad* products -- real "bend-o-matics", according to _Undercurrent_, which ran a series of horror stories on early decompression meters a few years ago (reprinted in their _Best of Undercurrent_, still in print). Their are NEWER meters, however -- e.g., the Edge, which supposedly works and is in use by more than 1000 professional divers at this time, according to the article in the most recent _Underwater USA_ (I can't recall who wrote that article off the top of my head, but he seemed to have good credentials -- one of his references that comes to mind is Dr. Bruce Basset, who's famous for the articles which argue for more conservative dive tables than the US Navy's, based on the amount of bubbling that he observed in divers who'd "pushed" the tables in controlled experiments). The article didn't mention the Deco-Brain, another of the newer decompression meters, but that also may be a good product: Hans Hass, a reputed European diving pioneer who was into rebreather diving in the late 30's, endorses the Deco-Brain, and has written about it at length. I'm not suggesting giving up the watch and tables -- only that good, automatic devices are coming out on the market to supplement such calculations. I'd guess the microprocessor revolution is making this possible. --- Phil Pfeiffer
mls@ittvax.ATC.ITT.UUCP (Michael Schneider) (08/02/85)
I have seen the table posted earlier when I bought my watch. When I first saw 50M..., I thought the M stood for meters. IT DOESN'T. It is just a marking to indicate the level of water resistance. So, I followed the table and got a 100M. So far, no trouble. m. schneider