Carbon Intensity Indicator, an operational measure introduced by the IMO that rates a ship's annual carbon emissions relative to the cargo carried and distance sailed. Ships are rated on a scale from A (best) to E (worst), and vessels rated D for three consecutive years or E in any year must submit a corrective action plan.
Also known as: Carbon Intensity Indicator.
Category: Marine Engineering
On The Maritime
The desks where this concept is measured.
In the Glossary
Carbon Intensity IndicatorCII
An IMO operational measure of how much CO₂ a ship emits per unit of transport work, graded A to E each year.
Read the full explanation in the GlossaryRelated terms
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Back to DictionaryEntry updated May 2026