CII rating
Carbon intensity per vessel, rated A to E. Illustrative in this build.
The Carbon Intensity Indicator (CII) compares how much CO₂ a vessel emits per unit of transport work with the level required for its type and size.
Attained CII
attained = CO₂ (g) ÷ (deadweight tonnes × distance in nautical miles)CO₂ comes from fuel burned, using the IMO conversion factors: 3.114 for HFO, 3.151 for VLSFO, 3.206 for MGO and 2.75 for LNG (tonnes of CO₂ per tonne of fuel).
Rating bands
The rating depends on attained ÷ required:
| Rating | Attained ÷ required |
|---|---|
| A | below 0.82 |
| B | 0.82 to below 0.93 |
| C | 0.93 to below 1.08 |
| D | 1.08 to below 1.28 |
| E | 1.28 or more |
Projection
Pruva fits a straight line through the monthly ratios and extends it to year end. A vessel at C that trends toward D shows the projected D months before the year closes. The assistant lists vessels projected at D or worse.
The bands use a single tanker reference vector and no correction factors. Real ratings need the ship-type vectors and the allowed corrections. Treat the ratings in this build as illustrative and check with your verifier before any filing.