CII: 2027-2030 Reduction Factors and New SEEMP Granularity
CII factors for 2027–2030, the enhanced DCS data timetable and SEEMP updates: connected topics with distinct rules and dates.
Operational Explanation
Z factors progressively lower required CII relative to the 2019 reference line. Enhanced DCS granularity concerns the data collected instead. SEEMP connects Part II collection methods with Part III planning without conflating these two changes.
Regulatory Reference
Scope of Application
Z factors apply to ships subject to CII; DCS fields follow their own scope. They are not percentage cuts in a ship’s absolute emissions or reductions to apply each year to the previous year’s result.
| Year | Z |
|---|---|
| 2026 | 11% |
| 2027 | 13.625% |
| 2028 | 16.250% |
| 2029 | 18.875% |
| 2030 | 21.500% |
Procedure / How to Complete It
- Distinguish entry into force of amended Appendix IX on 1 August 2025 from the collection timetable in Circ.913.
- For existing ships, prepare Part II before ordinary collection starts on 1 January 2026; early application from 1 January 2025 was encouraged. Ships delivered from 1 August 2025 collect the new data from delivery.
- Separate consumption by consumer, under-way/not-under-way consumption, total distance, laden distance, hours under way and onshore power according to the applicable method.
- Use the transport-work metric prescribed for the ship type; do not impose tonne-miles on every category.
- Update required CIIs and Part III measures for the relevant three-year period, accounting for the 2027–2030 factors.
Practical Example
Simplified numerical example. With reference CII of 10, required CII is 8.9 in 2026 and 8.6375 in 2027: 10 × (1 − 13.625/100). Do not reduce 8.9 by 13.625%. This illustrates Z only; rating also needs the relevant category and boundaries.
What Typically Goes Wrong
Similar field names may conceal different scopes. Under SEEMP guidelines, canal passage is excluded from the under-way period; its distance does not disappear from total distance. These collection definitions do not replace navigation-rule definitions.
Common Mistakes
| Mistake | Consequence | How to Avoid It |
|---|---|---|
| Applying Z to the previous year’s result | Required CII is calculated from the wrong base | Use the reference line prescribed by regulation 28.4. |
| Assigning new collection from 1 August 2025 to every existing ship | Ordinary collection is confused with entry into force | Apply the Circ.913 distinction, including delivery of new ships. |
What the PSCO Checks
Prepare the Part II methodology actually used and its confirmation, with applicable annual documents. Being able to explain the difference between total and under-way distance is more useful than producing two artificially identical columns.
Operational Tips
- Compare the data dictionary, onboard records and reporting fields.
- Integrate procedures for detecting and correcting missing data into the SMS, including meter failures; distinguish measured, estimated and corrected values with traceable reasons.
- Record onshore electricity in kWh and retain the supplier document supporting the total.
- Assign responsibilities, timing, expected outcomes and contingency measures to the three-year plan; verify Z factors against a known example.
Preparation checklist
- Ship-specific application timetable identified.
- Part II and confirmation consistent with the method.
- Total distance distinguished from under-way distance.
- Correct transport-work metric used.
- 2027–2030 factors applied to the reference line.
FAQ
Related Topics
Last substantive revision of this page: 15 September 2026 · page fingerprint 9c3af2326d44