Carbon Intensity Indicator Rating

Abbreviation: CII

Operational efficiency rating A–E assigned annually to ships >5,000 GT under MARPOL Annex VI.

In practice

Operators monitor CII through the year via DCS data. C-rating triggers operational measures (slow steaming, hull cleaning); D and E ratings trigger SEEMP Part III corrective action plan. Charter parties increasingly reference CII rating in clauses.

Regulatory detail & full definition

Carbon Intensity Indicator Rating — an annual operational efficiency rating from A (best) to E (worst) assigned to ships of 5,000 GT and above under MARPOL Annex VI Reg. 28. CII is calculated as grams of CO2 per cargo-tonne nautical mile, derived from IMO Data Collection System fuel consumption data, and compared with a tightening reference line (annual reduction factors set in MEPC.355(78)). Three consecutive D ratings or a single E require a corrective action plan in the Ship Energy Efficiency Management Plan; charter parties increasingly include CII-related clauses.

Authoritative source: MARPOL Annex VI (Air pollution) ↗

Source: MARPOL Annex VI Reg. 28; MEPC.355(78)

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Carbon Intensity Indicator Rating

In practice

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Carbon Intensity Indicator Rating

In practice

Related