Talk:Decompression theory

B-class rating

The article was split from an excessively large B-class article, and there was no immediately obvious reason not to rate it as B-class, as it comprises a fairly comprehensive section which is suitable for a stand-alone article after providing a suitable lead section. • • • Peter (Southwood) ^(talk): 19:40, 14 March 2013 (UTC)

Pyle

Through an AfC submission, it's come to my attention this particular term is a non-notable neologism. Of the 3 references used, 2 are written by Pyle himself, and one is a broken URL. If nobody opposes this, I'll go ahead and delete the subsection as unencyclopaedic. Best, FoCuSandLeArN (talk) 15:12, 3 August 2015 (UTC)

The term is used fairly frequently by technical divers, and the procedure is followed in practice by some technical divers. Divers may reasonably expect to find it mentioned and explained in an encyclopedia. I don't think it is given undue coverage, and I doubt that anyone with some knowledge of the recent history of decompression practice would consider the description in any way controversial. Please do not remove. I will look for a better reference. • • • Peter (Southwood) ^(talk): 16:14, 3 August 2015 (UTC)

The references written by Pyle describe the method he uses, which is an acceptable use of primary sources. • • • Peter (Southwood) ^(talk): 09:49, 4 August 2015 (UTC)

@FoCuSandLeArN: I have rewritten the section, with more references, more complete example, possibly better balance. Any comments? • • • Peter (Southwood) ^(talk): 09:46, 4 August 2015 (UTC)

Pbsouthwood I'm still worried about the sources used. I agree with your interpretation of WP:PRIMARY and do not object to the new text, however I do not see evidence this is notable, as the only references provided are very specific manuals and his own work. Do you agree, however, that the subsection is enough and we do not need an entire article about this? Cheers, FoCuSandLeArN (talk) 13:22, 4 August 2015 (UTC)

@FoCuSandLeArN: I don't see the need for a complete article only about Pyle stops, They are relevant in an article on Decompression theory or practice, and on the history of decompression, but probably not notable as a stand-alone. I do think that Richard Pyle may be sufficiently notable for a biographical article, but that is a totally different issue. In that case a section on his development of the deep stops which bear his name would probably be appropriate, but I don't do biographies as a rule. Notability is not the same thing as fame. A scientist may be notable without the same news coverage as an entertainer, politician or criminal, or one of the 'celebrities' who are famous mainly for being famous. • • • Peter (Southwood) ^(talk): 15:33, 4 August 2015 (UTC)

@Pbsouthwood: Is he this Pyle? If so, he probably scrapes past WP:PROF. I'll let the AfC submitter know and direct him/her here for comments. Best, FoCuSandLeArN (talk) 15:42, 4 August 2015 (UTC)

The same. He has published quite a bit on Pomacanthidae, including descriptions, some of which he discovered and collected himself on the dives which led to the development of Pyle stops. If you take a look at his CV linked from the rejected draft you will find he has published quite a few papers, both technical and popular. I have not read most of them, but you will see that he is not unknown. • • • Peter (Southwood) ^(talk): 15:52, 4 August 2015 (UTC)

Lede intro sect too long

Per WP:LEAD, the lede intro sect should be max four (4) paragraphs.

This one is eleven (11) paragraphs.

That's a bit long.

Could cause symptoms of TL;DR.

Strongly suggest trimming it down to size of four, succinct paragraphs, of four or five sentences each.

Good luck,

— Cirt (talk) 23:29, 14 October 2015 (UTC)

GA Review

The following discussion is closed. Please do not modify it. Subsequent comments should be made in a new section. A summary of the conclusions reached follows.

GA failed SpinningSpark 15:27, 26 November 2015 (UTC)

---

This review is transcluded from Talk:Decompression theory/GA1. The edit link for this section can be used to add comments to the review.

Reviewer: Spinningspark (talk · contribs) 15:51, 25 November 2015 (UTC)

Please don't be upset by this, but I am going to quick-fail this article. The page undoubtedly has the potential to be a good article, but the major problems are likely to take a while to sort out and a full review at this stage would be couterproductive as it would only need another review after the rework. You can resubmit the article any time you think it is ready. If you want, you can drop a note on my talk page when you have resubmitted it and I will take a look to save you having to wait in the queue again. Or you can wait for another reviewer, your choice. There are two major areas I am concerned about;

Lead

The lead needs to comply with WP:LEAD and is one of the six Good article criteria. It should be a summary of the article aimed at the general reader (not specialists). The lead should stand by itself as a mini-article if the reader reads only that.

• The lead is much too long. WP:LEAD recommends no more than four paragraphs. This issue should really have been addressed before submitting to GA, it was raised by another editor on the article talk page in October.
• Generally, the lead should not introduce new material that is not in the body of the aticle. For instance, the lead discusses mountaineers and astronauts but I don't see them even mentioned in the body of the article. By the way, I have never heard of either of them undergoing decompression so I would want to see an inline cite for that.
• You might want to consider a different image for the lead. Perhaps a photo of divers decompressing, or a picture of the various gas bottles used. The current image is too large and squeezes the text to the right. It also needs a good deal of prose to go with it before a reader is going to get anything out of such a complex graph. It would be better off somewhere in the prose where it can be centred and properly explained.

Citations

Large chunks of the article do not have inline citations. Many reviewers more or less insist on an inline citation for at least every paragraph. That is not actually a requirement and I would not insist, but not doing it does make it difficult to confirm verification. What is a requirement is that every statement in the article is verifiable in one or more of the sources and it is the duty of the reviewer to ensure that this is so. Using general references is a perfectly valid way of referencing an article on Wikipedia, but we will need to find a way for the reviewer to check verification without having to obtain a copy of every source and reading it from cover to cover. One possible way forward is for the reviewer to nominate sentences or facts they want to check and you provide the quotations from the source that verifies this. SpinningSpark 18:01, 25 November 2015 (UTC)

Hi Spinningspark.

I was hoping for something a little more practically useful to improve the article, but I will see what I can do with what you have provided.

• Could I trouble you to be a bit more specific in where you think more detailed in-line citation is necessary? I have a tendency to assume things are obvious or common knowledge where others with less familiarity with the subject and the basic physics and physiology involved may not. I am confident that I can find most if not all of the neccessary and desired references without much difficulty, since most of the uncited material is that which I considered basic and uncontroversial in the first place.

• Exposure to a reduction of ambient pressure is decompression. This happens when one ascends to altitude. I will try to make this more clear. There is a long history of decompression problems for this, and there are plenty of references. I will find one and insert it.

• It may be difficult to comply with the preference for a short lead and one which summarises the whole article. I will see what I can do. If you can suggest which parts can be omitted without depleting the summarisation too much, I would appreciate the guidance.

• Your point about the complexity and need for explanation of the current image is taken. It should not be difficult to find a replacement image for the lead, but it might not be as relevant. This is, after all, the article on decompression theory, as opposed to those on decompression practice, recompression therapy and other aspects of decompression.

• If there is anything that you think needs to be explained in more detail, or is unclear or ambiguous, please let me know.

Cheers, • • • Peter (Southwood) ^(talk): 19:30, 25 November 2015 (UTC)

Spinningspark. I have made a few changes and am adding citations inline. This will take a little while and I am adding what I consider more than strictly necessary. You may notice that in several sections the same reference is cited for each of the paragraphs. This is because they are all about the same thing and usually the same reference will cover the subject well enough to be usable. Where this is not the case I am using as many references as I think are useful to establish the point, but sometimes that requires a break between citations to fill the gaps, and some will take longer than others. It will be helpful if you would tag any sentences or paragraphs which you think specifically need citation so I can be sure not to miss them. Cheers, • • • Peter (Southwood) ^(talk): 08:15, 26 November 2015 (UTC)

Ok, the article has already been rejected and this page needs to be closed. The article can be submitted again when it is ready. If you want to come back to me do it on my talk page. What you need to do is carefully check the article against the GA criteria before submitting. I have highlighted two obvious areas of difficulty (particularly the lead), but a full review will look at all the criteria in detail. You did not get a list of simple actionable comments because I have not done a review in that depth, I did not consider the article to be ready for it. On the referencing, I am not requesting referencing for any one particular item, indeed I have not really done any reference checking. I have merely pointed out the difficulty you are going to have in relying on general referencing. But I also suspect that you have written the article as a subject matter expert, not directly referring to a source for much of it. While we appreciate expert editors here, you need to understand that they are not given a "free pass" on the referencing requirements. The requirements on Wikipedia are different from those in the academic community. Things you would not expect to have to reference in a scholarly paper will be expected here. We cannot assume that the editor is a subject matter expert (there is no system for checking) and you should not expect to get a subject matter expert for a reviewer (in all probability you won't). SpinningSpark 15:27, 26 November 2015 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

Solubility table

The table addressing the solubility of gases in fluids (water, lipid) is largely meaningless without units. mol per liter? liter gas per liter fluid?.... — Preceding unsigned comment added by 131.188.206.17 (talk) 13:46, 4 December 2015 (UTC)

GA Review

This review is transcluded from Talk:Decompression theory/GA2. The edit link for this section can be used to add comments to the review.

Reviewer: Daniel Case (talk · contribs) 03:54, 19 August 2016 (UTC)

I am sorry, but like Spinngspark I'm going to have to quick fail this article ... again.

Some of the issues raised in his review have been addressed but many still remain. To wit, a lot of uncited statements. Most are the end of otherwise-cited paragraphs; it seems that they have been added since the cites were added. This is uancceptable for a GA nominee. This is even more unacceptable when the previous review mentioned the same issue.

Here are just some examples of statements needing citation:

• "The main variable in the study of decompression theory is pressure."
• "In decompression theory the solubility of gases in liquids is of primary importance."
• "In decompression theory the diffusion of gases, particularly when dissolved in liquids, is of primary importance.
• "Tissues in which an inert gas is more soluble will eventually develop a higher dissolved gas content than tissues where the gas is less soluble."
• "... and there is a theoretical possibility of bubble formation."
• "As a consequence, the conditions for maximising the degree of unsaturation are a breathing gas with the lowest possible fraction of inert gas – i.e. pure oxygen, at the maximum permissible partial pressure."

And that's not even getting halfway through the article. Nor is it the only flaw.

The graph under "Saturation decompression" is a huge layout failure. It looks awful to have it poking into the space to the right of the article. Do something about it. Use {{wide image}} or considering redoing it so it can fit into the article the way images are supposed to.

The graphs under "Range of application" and "Deterministic models" are also waaaaay too large. Imagine what it's like to read this on a mobile device (actually, don't imagine, if you don't have one handy ... just load this into your browser and narrow it down to about the size and shape of a phone.

As noted on the talk page, the solubility table should list what unit is used to measure solubility. This was noted since the last review and hasn't been done.

There are also a lot of single-sentence paragraphs, and even one single-sentence section ("Breathing gas composition"). They should really be combined with adjacent sections or grafs. In fact, a lot of the subsections should really be joined together ... the article's table of contents is a nightmare of oversectionalization.

Frankly, the larger flaw is that it often seems to be trying to be a textbook rather than an encylopedia article. Remember summary style when deciding what to include and not include. Maybe all this is necessary, but I fear any reader, particularly one who feels the need to understand this, is going to feel as if someone was trying to assault them with text. At least as things now stand. Daniel Case (talk) 03:54, 19 August 2016 (UTC)

Some responses.

Daniel Case, Firstly, which criteria are you failing it on? Please refer to how it fails those criteria.

2b (many unsourced claims) and 3b (too much detail). Daniel Case (talk) 17:46, 22 August 2016 (UTC)

How many unsourced claims? I would have thought relatively few, and of those, mostly not contentious.

As for too much detail, I did not know that detail was a bad thing in an encyclopedia, particularly as I consider most of it necessary for reasonable understanding of the subject. Clearly you disagree, so could you specify which details are excessive, and why? • • • Peter (Southwood) ^(talk): 17:18, 23 August 2016 (UTC)

• Thank you for pointing out that some of the statements I thought were sufficiently obvious to not require specific referencing are not so obvious after all. I will try to reduce their number, but as these look obvious to me I may still miss some. Shit happens. Some of the statements you pointed out above as needing citation summarise what I would have considered obvious conclusions that anyone reading the article would make for themselves once they had read the rest, assuming that they paid attention and understood the basic concepts. Perhaps I was wrong.
  • For example, the uncited statement and there is a theoretical possibility of bubble formation. following mention of supersaturation is what supersaturation actually means in the context. This is mentioned with a reference two subsections earlier. Anyway I have referenced it again.
    • "some of the statements I thought were sufficiently obvious to not require specific referencing are not so obvious after all." Obviousness is entirely too often in the eye of the beholder. See WP:NOTBLUE for an essay-length discussion of this. Daniel Case (talk) 22:10, 21 August 2016 (UTC)
      • I agree with that in principle, that is why I put the article up for review, so that I could get feedback on what is not obvious. I have no objection to citing a claim that the sky is blue if someone asks for it, but do not intend to do so unless someone asks for it. Also NOTBLUE is an essay, not a GA criterion. • • • Peter (Southwood) ^(talk): 17:18, 23 August 2016 (UTC)

It's an essay, to be sure, but it's an excellent guide as to how and when to cite things. In short, err on the side of more often than not. Daniel Case (talk) 21:00, 23 August 2016 (UTC)

As far as I can see, all reasonably challengeable terminal sentences are now referenced. • • • Peter (Southwood) ^(talk): 16:37, 27 August 2016 (UTC)

• • I have sorted out most of the rest as they were relatively trivial, Waiting on information requested from some of my contacts for the last couple of items.
• The layout problem with the graph in saturation decompression comes as a slight surprise to me, it looks perfectly OK on my screen. I was unaware of the existence of {{wide image}} and will look into it. (looks useful, thanks for the tip)
  • I cannot find a requirement in the GA criteria for the article to display well on all platforms

That doesn't mean it isn't a good idea. Daniel Case (talk) 17:46, 22 August 2016 (UTC)

I concede that it is a good idea, but not that it is admissible a quick failure condition. particularly when no solution is suggested • • • Peter (Southwood) ^(talk): 17:18, 23 August 2016 (UTC)

• I was not aware that the GA criteria include appearance on a phone screen, and I don't use a phone for internet browsing as I can't read the screen. I will look into this.
  • I don't know what I should do about this. Are you suggesting that graphics that don't look good on a phone screen cannot be used in a GA? Something else? How should this problem be addressed?
    • GA criteria 1b includes compliance with MOS:LAYOUT, and within that section I commend WP:LAYM to your attention. No, it doesn't mention mobile screens (yet, anyway). But the general principles there will make an article that looks OK on a desktop or laptop not look too bad on a mobile. Daniel Case (talk) 21:00, 23 August 2016 (UTC)
      • I take it this refers to maximum width of 400px and maximum height of 500px? • • • Peter (Southwood) ^(talk): 07:06, 27 August 2016 (UTC)
• I have requested a copy of the source for the table of solubility. However it is the relative solubility that is important, and that does not actually have units - it is a dimensionless ratio. The actual units of solubility in water and lipids are irrelevant to the point, but I will try to get them in the interests of completeness. If I can't get then I will just delete those two columns.
  • The offending columns have been deleted as unnecessary detail. • • • Peter (Southwood) ^(talk): 16:37, 27 August 2016 (UTC)
• I will try to reduce the number of subsections.
  • The "Single sentence section" you refer to is the lead paragraph to several explanatory subsections that directly follow. Can you recommend a better way to handle this specific case?

Just so you know I'm doing this for policy reasons, see MOS:PARAGRAPHS: "The number of single-sentence paragraphs should be minimized, since they can inhibit the flow of the text" That's MOS, so it comes under GAC 1b. I would at least suggest including that in the section that follows. Daniel Case (talk) 20:52, 23 August 2016 (UTC)

That would be appropriate if the sentence applied only to the following subsection. When it applies to several subsections this becomes problematic, as hiding it in one subsection confuses the context. Minimising the number of single sentence paragraphs does not imply that they are not permitted at all, it is easy enough to specify that if it was the case. This implies that if a single sentence paragraph is the best way to present specific content, then it should be allowed. If you can suggest a specific way of presenting this content that is better than the current one, please do so, taking into account the actual case, and implications for the rest of the article. • • • Peter (Southwood) ^(talk): 07:18, 27 August 2016 (UTC)

I have now reduced the number and depth of subsections, and combined as many of the single sentence paragraphs as seems reasonable • • • Peter (Southwood) ^(talk): 16:37, 27 August 2016 (UTC)

• What do I do about it if the information is actually necessary to understand the subject? Who decides?

Since you have failed the article, Can I ask you to be helpful and actually tag those statements which you consider require specific citation?

I tried {{wide image}} on the saturation table graphic. It works fine on my wide screen, but actually looks far worse on your narrow screen example.• • • Peter (Southwood) ^(talk): 09:20, 19 August 2016 (UTC)

Solubility of gases table

Taking a step back from the request to add units to the table, is the table being used well? Duecker uses the table to make the point that nitrogen's fat solubility is higher than that of hydrogen, neon, or helium. Since nitrogen has, of the four, the closest fat solubility to that of anesthetics, he says one would expect from the Myer-Overton theory of anesthesia that nitrogen could cause intoxication at depth. None of that is communicated by the section of this article that contains the table. Solubility of the different gases comes up much later when nitrox and trimix are discussed, but neither the table nor the specific values in it are referred to explicitly. Something to think about before putting too much effort into tracking down Duecker's sources. --Worldbruce (talk) 06:22, 21 August 2016 (UTC)

What you're referring to, lipid solubility and the Meyer-Overton hypothesis, are discussed in Nitrogen narcosis. The narcotic effect of gases is not relevant to decompression theory and shouldn't be part of this article. I agree that the whole table isn't particularly relevant; the only entries of any real importance to decompression theory are the solubilities of nitrogen and helium (and arguably hydrogen) in serum and lipids, because those are the only gases likely to be involved in decompression. They need units if anyone is going to actually model gas absorption dynamics in body tissues, but otherwise it's just the relative solubility of helium and nitrogen in serum that is pertinent to the mechanism of isobaric counterdiffusion. --RexxS (talk) 17:22, 22 August 2016 (UTC)

This is correct, I would be happy to hear your recommendations. I would be quite happy to cut all the table except the relative solubilities of gases with decompression involvement. • • • Peter (Southwood) ^(talk): 17:04, 23 August 2016 (UTC)

I have deleted the columns without referenced units as irrelevant, and also the metabolically active gases. • • • Peter (Southwood) ^(talk):

Proposed split

In order to address some of the GA review objections to this article I intend to split out much of the material into two subsidiary articles: Physiology of decompression, and Decompression modelling, and summarise the contents of those parts of the existing article. As I am not expecting this to be controversial, I intend to just go ahead and do it some time soon. If anyone has useful suggestions for the split, please feel welcome to comment here. • • • Peter (Southwood) ^(talk): 07:55, 12 October 2016 (UTC)

Changed my mind about the second split and made it a redirect to this article. Keeping the option open for a separate article if it becomes necessary. • • • Peter (Southwood) ^(talk): 10:46, 16 October 2016 (UTC)

Things to do

Update with some of the work that has been done on comparison of efficiency of stop depth distribution, referencing Simon Mitchell's video on "What is optimal decompression" May 2020 on youtube https://www.youtube.com/watch?v=nIO9qI5XODw including:

• integral of total supersaturation over time and
• heat maps as a graphic representation of decompression stress distribution over Buhlmann tissues and time for comparative decompression schedules following various models starting as an interpretation of the results of the NEDU experimental decompression series comparing a bubble model (deep stops) with a dissolved gas model (shallow stops) which showed better results for shallow stops.
• evidence regarding the usefulness of deep stops. · · · Peter Southwood ^(talk): 16:12, 29 September 2021 (UTC)
• also Doolette DJ, Mitchell SJ. Recreational technical diving part 2: decompression from deep technical dives. Diving and Hyperbaric Medicine. 2013 June;43(2):96-104. https://www.eubs.org/documents/DHM%20vol43%20no2.pdf · · · Peter Southwood ^(talk): 06:34, 30 September 2021 (UTC)
• More resources:
  • https://www.youtube.com/watch?v=dYIux8KbUKo Deco theory with Prof. Simon Mitchell, part 1/3: Contributing factors to decompression stress
  • https://www.youtube.com/watch?v=AicUyu4WGA0 Deco theory with Prof. Simon Mitchell, part 2/3: Gas density and CO2 retention
  • https://www.youtube.com/watch?v=28_wM9CXXQ8 Deco theory with Prof. Simon Mitchell, part 3/3: Deep Stops, the good the bad and the how we changed

· · · Peter Southwood ^(talk): 07:11, 1 October 2021 (UTC)