| Code |
Explanation |
| M1 |
Meteorology Agency 130cm closing net |
| ML |
Multiple net |
| NS |
Nansen net |
| WS |
International standard net |
| KH |
Kitahara quantitative net |
| MO |
Meteorological observation net |
| NP |
NORPAC plankton net |
| HS |
Hensen quantitative net |
| OR |
ORI net |
| IS |
Indian Ocean standard net |
| I8 |
Indian Ocean survey 80 cm closing net |
| MT |
Marutoku net |
| MN |
Marunaka net |
| MC |
Meteorological C net |
| JD |
Tropical Judy net |
| CC |
CalCOFI standard net |
| BO |
Bongo net |
| WP |
UNESCO WP-2 net |
| 05 |
0.5m quantitative net |
| R1 |
RMT-1net |
| R8 |
RMT-8 net |
| MS |
MOCNESS net |
| BI |
BIONESS net |
| I1 |
IKMT 10ft net |
| I6 |
IKMT 6ft net |
| KO |
KOC net |
| MD |
MTD net |
| CB |
Clark Bumps net |
| TC |
Tucker net |
| CJ |
Clarkjet |
| MV |
MTD-V |
| HC |
Hardy continuation |
| G3 |
Gulf III |
| ML |
Miller (small type Hardy) |
| LH |
Long Hurst Hardy |
| NW |
Newstone |
| SL |
Sled net |
| TR |
Trap |
| ET |
Other nets (including blanks in the observation data) |