Since I took my OW training through SSI and the dive table I first learn to use was the SSI table, I have been using the SSI dive table out of habit, even when my other certifications is PADI. My regular dive buddies uses the PADI table or the Norwegian Standard table, during dive planning I observed that the other divers usually required shorter SI between dives and allowed longer NDL times than my SSI dive table would allow.
That made me curious so I went online with my trusty visa card and bought a copy of the most used dive tables in my area to compare them and find the table that suits me better (less conservative than the SSI table), so today the mail-man delivered a little package with the PADI, US Navy and Norwegian Standard tables, and now it was time to compare with 5 test cases for NDL and 5 test cases for SI.
My initial bias was that there would be two pairs of similar results SSI + PADI and US Navy + Norwegian standard when comparing NDL and SI.
I was a bit surprised by the result, seeing that Norwegian standard was the second most conservative table and that PADI was the second least conservative one.
Test case 1 NDL:
First dive: 22 meters - 30 min
Second dive: 18 metes
First dive: 18 meters - 40 min
Second dive: 12 meters
First dive: 35 meters - 10 min
Second dive: 10 meters
First dive: 12 meters - 30 min
Second dive: 30 meters
First dive: 25 meters - 20 min
Second dive: 22 meters
That made me curious so I went online with my trusty visa card and bought a copy of the most used dive tables in my area to compare them and find the table that suits me better (less conservative than the SSI table), so today the mail-man delivered a little package with the PADI, US Navy and Norwegian Standard tables, and now it was time to compare with 5 test cases for NDL and 5 test cases for SI.
My initial bias was that there would be two pairs of similar results SSI + PADI and US Navy + Norwegian standard when comparing NDL and SI.
I was a bit surprised by the result, seeing that Norwegian standard was the second most conservative table and that PADI was the second least conservative one.
Test case 1 NDL:
First dive: 22 meters - 30 min
Second dive: 18 metes
Tabel | NDL dive 1 | NDL dive 2 | RNT before dive 2 |
SSI | 30 min | 25 min | 24 min |
PADI | 37 min | 45 min | 11 min |
Norwegian Standard tabel | 30 min | 30 min | 30 min |
US Navy | 40 min | 40 min | 20 min |
Second dive: 12 meters
Tabel | NDL dive 1 | NDL dive 2 | RNT before dive 2 |
SSI | 50 min | 69 min | 61 min |
PADI | 56 min | 112 min | 35 min |
Norwegian Standard tabel | 60 min | 60 min | 75 min |
US Navy | 60 min | 151 min | 49 min |
Second dive: 10 meters
Tabel | NDL dive 1 | NDL dive 2 | RNT before dive 2 |
SSI | 10 min | 135 min | 25 min |
PADI | 14 min | 199 min | 20 min |
Norwegian Standard tabel | 10 min | 95 min | 40 min |
US Navy | 15 min | 285 min | 25 min |
Second dive: 30 meters
Tabel | NDL dive 1 | NDL dive 2 | RNT before dive 2 |
SSI | 130 min | 6 min | 14 min |
PADI | 147 min | 12 min | 8 min |
Norwegian Standard tabel | 135 min | 5 min | 15 min |
US Navy | 200 min | 11 min | 14 min |
Second dive: 22 meters
Tabel | NDL dive 1 | NDL dive 2 | RNT before dive 2 |
SSI | 25 min | 17 min | 13 min |
PADI | 29 min | 32 min | 5 min |
Norwegian Standard tabel | 25 min | 10 min | 20 min |
US Navy | 30 min | 27 min | 13 min |