Free SSI Science of Diving Specialty

[scubadada]

I can honor the Nitrox for you no worries. Some SSI shops were getting upset with the attention this thread was getting so SSI requested me to remove the pricing. But I'll still honor it for you. what was your name on the email you sent?

Hi Henry,

I sent you a PM.

Thanks much, take care,

Craig

 

[dmaziuk]

DSAT developed the PADI dive tables in 1988 to support recreational diving wheras SSI continues to base their tables off the U.S. Navy dive tables. I have read, but do not know for sure, that DSAT used the 60min tissue compartment as the controlling compartment for their table, which would allow for more repetitive dive dive time with shorter Surface Intervals; this would seem to match the audience they were catering too as recreational divers want to get more dives in with shorter SIs than a navy diver would (as gas supply is more likely the controlling factor).

You need to remember that base model is symmetrical and for every hour spent on the surface (off-gassing) you have to spend at least as much underwater just to keep your overall gas loading the same. Basically if you're doing OC no-stop dives you'll never load your slower compartments: every 8 hours of sleep is 8 hours off-gassing in slow tissues.

IRL DSAT did manage to bend their test diver and concluded that a) don't go over 5 tanks/day and b) take every 6th day off, if you're diving those shorter SIs and trying to max out on bottom time.

DSAT report has the details and is available for download free of charge from the Rubicon Foundation site near you.

Navy's Thalmann/VVAL is not symmetrical, but I don't know when/why its off-gassing rate changes, nor whether SSI tables are rooted in it.

 

[TMHeimer]

Regarding the tables-- I'm surprised all the dive agencies don't have exactly the same tables. After all, those who made them up are certainly in the forefront of DCS study. You'd think there would be an agreement on one way that (probably) is safest.
Then again, look at the different drinking ages (18 in Western Canada, 19 in the East and 21 in the U.S.). Used to be 21 in Canada and 18 in the U.S. during Vietnam. I guess the rules are right if we say they're right.

 

[wetb4igetinthewater]

Along the way I read "The Encyclopedia of Recreational Diving", by PADI and "The Certified Diver's Handbook" by Coleman. Would there be a benefit to taking this SSI online course?

I really liked Coleman for diver starting out.

I wasn't aware of the Coleman book. Just bought off Amazon. Well reviewed. Thanks for the addition to my dive library (which I loan to students).

 

[loosenit2]

Navy's Thalmann/VVAL is not symmetrical, but I don't know when/why its off-gassing rate changes, nor whether SSI tables are rooted in it.

If you look at sub-title of SSI tables. "Doppler no-decompression limits based on US Navy Dive Tables". I think it is reasonable to conclude that the SSI tables are based on the Navy Tables, with an update from the ?76? Doppler bubble study.

 

[dmaziuk]

If you look at sub-title of SSI tables. "Doppler no-decompression limits based on US Navy Dive Tables". I think it is reasonable to conclude that the SSI tables are based on the Navy Tables, with an update from the ?76? Doppler bubble study.

:shrug: does it say from what year? Wikipedia puts USN tables at "1916 on", I'm pretty sure back in 1916 it would've been Haldane's original model. Thalmann-VVal-18M is dated 2007, you could compare table F1 in it: http://archive.rubicon-foundation.o...123456789/8349/NEDU_TR_2007-09.pdf?sequence=1 to SSI one to see if they're the same.

 

[saxman242]

:shrug: does it say from what year? Wikipedia puts USN tables at "1916 on", I'm pretty sure back in 1916 it would've been Haldane's original model. Thalmann-VVal-18M is dated 2007, you could compare table F1 in it: http://archive.rubicon-foundation.o...123456789/8349/NEDU_TR_2007-09.pdf?sequence=1 to SSI one to see if they're the same.

 

[dmaziuk]

Now y'all know what the word "provenance" means... hopefully they've similarly documented their "computers can't do sawtooth profiles" thing in one of those cards.

 

[tursiops]

Truely a strange set of tables. They claim to be based on Navy tables, but not on any published Navy tables I am aware of.
They appear to use Navy tables but subtract 5 mins from each NDL for depths 90-130 ft, and then for 60-80 ft they subtract 5 mins from the old NAUI tables, which themselves are Navy-based plus additional conservatism. Apparently the "- 5 mins" is justified by the 1976 work of Spencer. So if you don't like dive computers with mysterious safety factors built in, here you go with the table equivalent.

 

[TMHeimer]

At @Sloeber 's request, the original post has been edited. Looks like the specialty is now being offered at half off rather than free due to some pushback.

I just finished the Final Exam last night and am supposed to forward the form, etc. in order to receive the cert. Is it still free for those who have finished?