Talk:Scuba diving

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1 Under remodeling
2 Breathing Underwater
3 History Of Diving
4 Discussion
5 Need to see underwater
6 Note regarding latest edits to 'Need to see'
7 Refraction and underwater vision
8 AdSpam Policy
9 Training and certifying agencies
10 External links
11 Fix first sentence
12 external link to canary diving adventures
13 external link to ABC of Diving
14 Scuba flags
15 AdSpam policy - again

[edit] Under remodeling

I am currently completely redoing this article, so some articles may be deleted. Thank you, --Tvaughn 23:54, 2 May 2005 (UTC)

[edit] Breathing Underwater

I've added a lot to the Breathing underwater section, but it may be too much detail for this page. I think I need some help making it accessible as an intro... Cheers, --Arkayik 03:49, 19 May 2006 (UTC)

What is BCD a the end of the "Injuries due to changes in water pressure" section? Needs either a link or a expansion of the acronym. --Mycroft007 17:08, 21 December 2006 (UTC)

[edit] History Of Diving

This section has nothing to do with SCUBA diving. A history/development of SCUBA would surely be more relevant. Breathhold, diving bells, snorkelling and surface supply are not SCUBA because they are not self contained. . Perhaps a 'Diving (Underwater)' article should be added that covers all forms of underwater ambient pressure activity? It could replace the currently awful 'underwater diving' article. Any thoughts? TDIPete 14:36, 4 March 2007 (UTC)

Can someone please remove the arrows in the History Section? Thanks. --Tvaughn 00:21, 4 May 2005 (UTC)

[edit] Discussion

Statements as the one that said narcosis could be controlled by someone, refer to what might happen in one case over some thousands (and I personally have in mind only one lucky case, in which an athlete was able to inflate his equilibre jacket - GAV - to reach the surface again from -75, but it has not been cleared yet if this was made volountarily).

Please, be wise in not creating false myths in a subject that has many references to death. Objectively, scuba diving can be dangerous if rules are not respected, and what in that sentence was completely out of a reasonable mature mentality of immersion.

Also, it might be advisable to specify that single "special scores" are not meant available to anyone's attempts. Records are achieved by highly athletic individuals, not by ordinary people.

"Leonardo da Vinci affirmed in his Atlantic Code (Biblioteca Ambrosiana, Milan) that [etc.]."

Should it not rather be "Atlantic Codex"?
S.

Atlanticus Codex in Latin (Codex Atlanticus is the Italian habit for modern use of Latin and - perhaps - how it is classified in librarians' style, but it's a little less pure), Atlantic Code in English.

Choose one :-) [G]

This page still needs some work. There is big difference between decompression sickness (the bends), nitrogen narcosis, and various emboli that can be sustained by rapid decompression. I'll work on it.
--Bob Jonkman, ACUC Level II instructor 903EA

I am very suspicious of the information in here. I think someone with minimal knowledge just wrote what they thought. I have corrected some of the more glaring errors. Someone with more detailed knowledge really needs to work on this. Bob Jonkman, are you still there? DJ Clayworth 14:49, 14 Aug 2003 (UTC) (P.S. does anyone actually have examples of people diving from kayaks, or ocean liners?)

SirScuba, do you have a reference for 'diving has fewer deaths than bowling'? It seems unlikely, simply because I find it hard to imagine a way in which you can kill someone while bowling.

Also, whoever is doing this, you need to leave a space after the external link before the closing bracket, or the external link doesn't work i.e. you need to write (mypage.html ) not (mypage.html). DJ Clayworth 17:57, 14 Aug 2003 (UTC)

reply from sirscuba

dive kayaks http://www.sonic.net/~rocky/kayaks.htm

Ocean liners - there was a cruise ship "ocean spirit" ? that catered to divers, they launched inflatables to take the divers to the sites. I think they stop operation several years ago.

A few years ago a study was done, after crunching the numbers bowling was more dangerous than scuba, i see if i can find a link. Heart attack, choaking on food, slipping and falls, smoking, drinking, fights all happen at bowling alleys. I'll bet the number of death due to contact with a bowling ball are small.

The PADI Rescue Diver Manual (Copy write 1995 ISBN 1-878663-09-7) on page 30 in a side bar prints this "scuba ranks low in injury occurrence according to figures in the 1991 edition of the US National Safety Council accident facts. American Football comes in at 217 accidents per 10,000 participants annually Scuba Diving comes in at 4 per 10,000" "Activity injury incidence American Football 2.17% Baseball 2.09% Basketball 1.86% Football Soccer 0.91% Volleyball 0.37% Waterskiing 0.20% Racquetball 0.17% Tennis 0.12% Swimming 0.09% Bowling 0.04% Scuba Diving 0.04%" Please Note that this is for injuries not for deaths. As this is required reading for the PADI Rescue Diver Course this data might have been misrepresented and should be clarified. Fred Tittle PADI Master Scuba Diver Trainer 164579 SSI (Scuba Schools International) Dive Con Instructor 25265

I removed 'embolia' from the list of diseases because it turns out that medically 'embolia' means The reduction of a limb dislocation] and is not the plural of embolism. Since I'm not sure that embolism was what the original author meant, I'm taking it out.

SirScuba, I think the quote about bowling is misleading. For a start you need to say per thousand what (per thousand hours spent doing the sport? per thousand people taking part?). I think it's also obvious to everybody that for any given person they are more likely to die from an hour spent doing Scuba than from an hour spent bowling. Insurance companies, who are usually very good at working out the statistics of these things, put scuba in a higher danger category than bowling (higher also than golf, basketball and jogging). Most of them put scuba in the same category as things like white water rafting and American Football, but lower than say hang-gliding or luge. Even then there is a depth limit of 25m. DJ Clayworth 15:58, 25 Aug 2003 (UTC)

The statistic is based on number of injuries requiring a hospital visit per 10,000 participants per annum. Dont have one handy but I believe it is in chapter one of the Open Water (PADI) manual if some one wishes to verify TDIPete 13:59, 4 March 2007 (UTC)

For "obstruction", the singular is embolus and the plural is emboli. Anthony Appleyard 14:23, 12 Dec 2004 (UTC)

OK - i removed the bowling reference & added verbage to the "death" comment

[edit] Need to see underwater

The article says: "Diving masks and diving helmets solve this problem. Occasionally commando frogmen use special contact lenses instead." Could someone give some more information about this? Google only gives links to people discussing the possiblity. Jarvik 23:30, 2 December 2005 (UTC)

Contact Lenses *

Commando frogmen will use these lenses in order to see underwater while eliminating the relatively large glass surface of a diving mask which can reflect light and give away the frogmans position.

200.233.51.145 16:26, 11 February 2006 (UTC)

Umm....Not exactly a great reference. While soft contact lenses are safe to wear while diving (with a mask), trying to use contact lenses as an alternative to a dive mask is pretty unpractical. Ignoring the fact that contacts don't cover the entire eye, there's the issue of keeping them in place. Water's a pretty dense substance, and swimming against a strong current or general wave surge would be more than enough to dislodge a contact lens -- and that's without taking the use of diver propulsion vehicles into consideration.

I don't know what the rest of the world's military divers are using, but I do know that the United States military has adopted Oceanic/Aeris's "Integrated Diver Display Mask". It's a very neat system, a basic "Heads-Up Display" that allows divers to monitor depth, bottom time, tank pressures and related information while leaving their hands free for other tasks. JEJoyce 11:28, 14 February 2006 (UTC)

The contact lenses referred to were first developed in the early 1960's. US patent #3,311,577 refers to magazine articles (e.g. Sports Illustrated) that detailed these lenses. This patent makes claims for a highly viscous saline solution to be used in conjunction with large diameter sclera contact lenses. Sclera lenses would remain in place with eyes open underwater, however they were quite uncomfortable. A topical anesthesia was sometimes applied. Two more recent patents related to improving this concept are US patent 5,831,713 and 6,048,063. The Navy encouraged these developments not so much for reducing reflections above water but rather for expanding the narrow field-of-view caused by conventional flat masks, which reduces situational awareness and the mission effectiveness of military "operators" (divers).Jon Kranhouse 09:12, 26 February 2007 (UTC)

They have been used by freedivers to prevent wasted air in mask equalisation, initially developed by Jaques Mayol if memory serves. I've never heard of them being used by the military. They would presumably need to be removed in order to be able to see clearly above water so would be a no-no for any mission which might possibly require surfacing. Also in polluted water or water with suspended particles (harbours or beach recon anyone?) they would be less than ideal. On top of that the possibility of them falling out (check out some of the freediving forums) seems to make them highly impractical for military applications. All sounds a bit James Bond to me. Oh, they also need to be custom made for individuals. TDIPete 13:45, 4 March 2007 (UTC)

[edit] Note regarding latest edits to 'Need to see'

I reverted the latest edits to this section because the new (much shorter) version did not adequately explain why the effect happens, nor why the mask helps correct it, IMO. It also incorrectly implies the reason for the distortion is that light traveling thru water causes it, vs. the correct reason that it is the interface between water and eye (vs. air and eye when outside the water or when wearing a mask) that creates the focusing problem. If I wanted to expand on this, I would mention that having a mask on is like looking inside a pond with a glassy surface, or looking inside an aquarium. Crum375 11:14, 11 June 2006 (UTC)

I made the amendments that you reversed. First, it's misleading to say that light travels slower in water than in air, because you're implying that the speed of light (i.e. signal velocity) is changed. It's only the phase velocity that's changed. I agree with you that my version's use of the world "through" is misleading, too, so perhaps it should be changed to say something like:

"Water has a higher refractive index than air. Light entering the eye from the water behaves differently than light entering from air. This creates a distortion that affects normal vision."

Second, an article on scuba diving should not go overboard on explaining refraction. A short explanation of the effects plus a link to the scientific article that details the phenomenon is more appropriate.

Third, I think that saying that the light will be focused is inaccurate. The air in the mask reverses the refraction, but has nothing to do with focusing light (i.e. act as a lens). gisarme 60.234.232.62 01:43, 18 June 2006 (UTC)

I agree with one point you make: that we should not go overboard in describing refraction per se. But I think I disagree on some of your other points, which I will try to explain. When an object emits light (normally by some type of reflection) within a given medium, a lens can focus the light rays to recreate a 2D rendition of the object on a surface (such as the eye's retina). The lens operates by refraction, and refraction is determined by the relative speeds of light (technically phase velocities) in the adjacent media. The reason a human's eye cannot focus clearly underwater is simply because the eye's lens is designed to focus (or refract) rays that arrive from an air medium into the eye's or lens' medium (actually a complex of several structures and media which I am simplifying for now), which is close to water in refractive index. Note that it is the difference between the refractive indices of the lens and the surrounding medium that determines (by Snell's Law) the actual refraction or bending of the light rays. When the light rays arrive from a water medium, the eye's effective refractive power is drastically reduced, since the lens and the surrounding medium are now so close in their refractive indices. This produces a focal plane well behind the retina and hence a very blurry 'off-focus' image on the retina itself. If we now introduce an air gap between the eye and the water medium, where the water-facing side of it is flat (similar to observing a flat-walled fish tank from outside), then that flat side will only produce a magnifying effect (which I will skip for now) but the rays entering the eye from the airgap will be properly refracted and focused since the difference between the lens and the medium is now back to 'topside' normal and hence the focal plane will fall into its normal location on the retina. Crum375 03:22, 19 June 2006 (UTC)

[edit] Refraction and underwater vision

1. Changed sub-head to more precisely address the topic and be consistent with other sub-heads (i.e. "Need to see" would be like "Need to breath" or "Need to not get the bends").

2. Refraction errors are reduced but not completely eliminated by flat dive masks. Added brief explanation of refractive distortions. This web page, not cited in article because of its business agenda, indeed has accurate details and illustrations:[1]

3. Deleted statement that a prescription “grind” can be put into a normal mask. Since 1987 the scuba industry in the USA has voluntarily agreed to use lens material at least as impact-resistant as tempered glass. The geometry of an Rx would violate the minimum thickness of this safety standard... but the tempered glass would break before a "grind" would even be possible. The shaping of a glass lens must be done before heat or chemical tempering. With CR-39 optical polymer, found on precious few masks, the grind would likewise violate minimum thickness requirements.

4. Brief addition of how generic and custom vision Rx is manufactured for modern masks.

5. Added brief info about a new type of dive mask, available since 2003, that expands underwater field-of-view almost 5X vs. all flat masks and eliminates refractive errors common to all flat masks. Statements in article are accurate and avoid "puffery." Besides the HydroOptix company’s claim for a true breakthrough in underwater vision, much validating information is available (e.g. the web’s most popular scuba forum: http://www.scubaboard.com). Jon Kranhouse 10:00, 26 February 2007 (UTC)

[edit] AdSpam Policy

I am not sure what the 'official' WP policy is re AdSpam, but I know that all we want here is pure relevant sources to back up information in the article, and then perhaps some sites for 'further reading'. I think any site that proposes to sell anything (like equipment, trips etc.) should be almost automatically vetoed. Sites like DAN, PADI etc. in my opinion are eligible despite having some items for sale because they are so well known and focus on safety.

I think another issue should be a maximal link count - WP is not Google and does not supply links, except the most essential ones needed to understand the article. I think right now there are way too many links, and I would urge anyone to read through them and weed them down to the most essential per the above - the less non-essential links the better. My guess is that if some anon IP desperately tries to re-insert a removed link, while possibly removing competing links, that by definition is AdSpam. Crum375 21:29, 13 June 2006 (UTC)

I went through the ads and chopped off some myself. If anyone truly believes that what appears on the surface as adspam is actually essential for this article, make a case here first, get a consensus to agree, and it will stay. Otherwise the ad will just be reverted by anyone who believes that these unnecessary commercials clutter the article. Thanks, Crum375 21:36, 13 June 2006 (UTC)
As SCUBA diving has no central official sanctioning body, I agree that the main certification agencies (as SSI that was just anonymously added) should be retained as external links. Crum375 21:52, 7 July 2006 (UTC)
As there is again a buildup of external links, I would strongly encourage any future contributor to that section to carefully review the external linking policy before doing so. Thanks, Crum375 15:01, 8 August 2006 (UTC)
I am not spamming. I have no financial connection with these firms. The existence of these diving firms is a notable fact, whether or not they accidentally benefit from Wikipedia mentioning them. By this logic, JCB page better not point to the JCB firm's web site, and hundreds of similar examples. We are not in the years before Ralph Nader when public newspaper articles dared not mention a trade name, with a taboo of religious-type dreadedness. Anthony Appleyard 16:06, 8 August 2006 (UTC)
I have again checked through these links. None is to an individual scuba gear dealer. Admittedly many of them are heavily loaded with advertisements to pay for the costs of running the web sites. It looks like that the previous editor merely chopped a length off the front of the list. Anthony Appleyard 16:14, 8 August 2006 (UTC)

Anthony, I have no doubt in your sincerity, and I am not suggesting you are spamming, but I do suggest you read up on WP:EL. The issue is not just 'spam' per se in the form of commercial ads - it relates to all external links, even ones that sell nothing. Ideally, the perfect WP article should have no external links, or nearly none. The case you mention would be one of the few exceptions - a link pointing to a Web site belonging to the subject of the article is always acceptable and even recommended. In our case, the subject is an activity, so this does not directly apply. In general, the WP spirit is that any useful factual information in an external link should be incorporated (over time) into the main article, with a reference to the link if needed, and the external link then either disappears (if the info is also sourced elsewhere) or is moved into the direct reference list if cited. So again, please carefully review WP:EL, try to understand its spirit, and decide for yourself which of the external links you think are absolutely crucial and meet the WP:EL criteria. I'll refrain from reverting for now to give you a chance to work on it, although the better way is to work backwards by adding the crucial links. Thanks, Crum375 16:25, 8 August 2006 (UTC)

As a correction to my above message, even the case you mention would normally be no exception. In a case of a commercial site that belongs to the subject of the article, it would normally be cited as a reference, not as an external link. If it is cited as an external link that would still be OK, but unnecessary, as it would normally be better to have it as a reference. Crum375 16:31, 8 August 2006 (UTC)

Of course, ideally all the certification agencies mentioned would link to a corresponding Wiki page, which would then link externally, ergo those that insist on certain agencies should start appropriate Wiki page son those agencies, and then link from here to them :-) Rcnet 11:23, 22 November 2006 (UTC)

[edit] Training and certifying agencies

I added this section as I think it is very pertinent to Scuba diving. I also hope that by getting PADI et al. mentioned in this section, we can reduce the amount of external links. Per WP:EL we really should have a bare minimum of external links, but that's another ongoing issue that needs addressing. Anyone with time and knowledge (i.e. good sources) feel free to improve this section. Thanks, Crum375 14:45, 12 August 2006 (UTC)

I have added edit comments to that section to try to explain that these are strictly the most important internationally recognized certification agencies. I also think that each member of this list should have a well-sourced existing article explaining its prominence and its international recognition. Other agencies should possibly go to List of diver training organizations, if they otherwise qualify. Crum375 13:36, 25 March 2007 (UTC)

[edit] External links

I am quoting from WP:EL, what should not be included as External Link:

Any site that does not provide a unique resource beyond what the article here would have once it becomes an example of brilliant prose.

As I see it as a possibility that one day this article could become featured, I think we should aim in that direction starting today. Any external link added should be explained and justified carefully in this Talk page, per WP:EL criteria, or it can be removed by anyone, per WP policies and guidelines. Thanks, Crum375 14:56, 12 August 2006 (UTC)

[edit] Fix first sentence

Anyone got some proposals for a rewrite of this?

Scuba diving is the term used to describe the use of a self-contained breathing set to stay underwater for periods of time greater than the average individual can breath-hold.

At least drop the last part "than the average individual can breath-hold" in the process, as it makes no sense - No one could ever even approximate the time differences involved. Rcnet 11:19, 22 November 2006 (UTC)

[edit] external link to canary diving adventures

hi everyone we are a dive center in gran canaria and we would like you to link to our web site, we are a Padi 5 star gold palm resort we recognise all dive organisations & qualifications, but mainly teach Padi, we do all courses from beginners in our pool right up to dive master, we are based in the bay of taurito a small secluded bay in gran canaria next door to a 4 star hotel of which all our guests are welcome to use the faciilities whilst waiting to dive, in return for a link we would like to offer discount to all the readers of your site, thank you Sam [2] sam@canary-diving.com Crambo 11:07, 11 January 2007 (UTC)

Sam, thank you for the information about your business. Unfortunately, Wikipedia is not the Yellow Pages, and we cannot link to your site from here, see also our external link guideline. Thanks for understanding, Crum375 12:38, 11 January 2007 (UTC)

[edit] external link to ABC of Diving

Hello there... I have included a link to 'ABC of diving' in this page sometime ago and before that I'm a regular watcher,observer, and contributor that is, aiming to remove the tag that was placed in this page so it to conform to every standards (standards, that is, that should just to used as a BASIS) needed. And in my surprise "ABC's of Diving - Basics of going scuba diving" is no longer available in the External links section. Before one should say things "like please stop adding ads as external links or cert schools - see Talk" AND "Rvt - please discuss on Talk page" -> Crum375. I would suggest that this website be seen first before posting any word. As I've said I'm appealing to each and every contributors who in one way or another knows how to really value and see what QAULITY, CONTENT and IMPORTANCE mean using their human understanding with the help of a guideline which should JUST be used merely as a GUIDELINE and not supposed to be in full control of ones human understanding. Thank you! Reader contributor 12:20 PM, 15 March 2007

Please see the "AdSpam policy - again" section below. Thanks, Crum375 04:25, 15 March 2007 (UTC)

The reason it keeps getting deleted is that it has a store or links to stores which is promotion and reads like an advert rather than pure unbiased information about diving if that helps you at all. Darth griz⁹⁸ 04:27, 15 March 2007 (UTC)

Endorse Removal of link as it has become apparent that it is part of a pattern of spam from User:Reader contributor. From his/her user page, it is apparent that s/he works for the company responsible for the website that s/he keeps spamming into articles. Please see WP:COI and WP:EL on why a link to a commercial website that you are trying to promote keeps getting deleted. Leuko 04:32, 15 March 2007 (UTC)

I call spam as well. Spartaz ^Humbug! 07:07, 15 March 2007 (UTC)

[edit] Scuba flags

Ok, I don't want to just delete these so I'm going to ask, why are there random scuba flags scattered throughout the article? Is somebody diving there? (never mind bad diver joke) But it just seems that the article only needs one, or maybe two but different flags such as the blue one and the red one, but not 4 red ones or what ever number is there now. Darth griz⁹⁸ 02:11, 7 February 2007 (UTC)

Good catch. Someone must have snuck them in ;^) Crum375 02:54, 7 February 2007 (UTC)

Changing 'SCUBA Flag' to 'divers down' flag as it denotes any diving operation not just Scuba.TDIPete 14:14, 4 March 2007 (UTC)

[edit] AdSpam policy - again

There is a constant barrage of various promoters of commercial sites that are trying to use Wikipedia as an advertising vehicle. Please read WP:EL, WP:NOT, etc. This article is about Scuba Diving, and it should remain an encyclopedic description of that topic. As a reference point, go check EB and see how many ads it carries on its Scuba Diving entry. Please refrain from adding advertising materials here. Thanks, Crum375 03:44, 15 March 2007 (UTC)

For convenience, I am pasting here from the old AdSpam section: