The required EEXI reduction factor table and when an EEDI value can stand in (MARPOL Annex VI Regulation 25)

EEXI is calculated from a ship’s design and specifications. It is not an annual operational rating like CII. The calculation and verification date, major conversions, and conditions for using an existing EEDI value need to be checked.

Ships that have undergone a major conversion are inside the scope

Regulation 23 has the attained EEXI calculated for each ship and for each ship which has undergone a major conversion, within the ship type categories the Annex lists.

That major conversion is written as its own item shows what kind of index this is. It is not a value settled once and for all; where the ship’s specification changes, it is calculated again.

Verification rests on the technical file

The attained EEXI shall be specific to each ship and shall indicate the estimated performance of the ship in terms of energy efficiency, and be accompanied by the EEXI technical file which contains the information necessary for the calculation of the attained EEXI and which shows the process of the calculation. The attained EEXI shall be verified, based on the EEXI technical file, either by the Administration or by any organization duly authorized by it.

Two things have to be in the technical file: the information necessary for the calculation, and the process of the calculation. A document carrying only the result does not meet the requirement.

The verifier is the Administration or an organization duly authorized by it, and what the verification rests on is that technical file.

There are conditions for using an EEDI value as the EEXI

3 Notwithstanding paragraph 1 of this regulation, for each ship to which regulation 22 of this Annex applies, the attained EEDI verified by the Administration or by any organization duly authorized by it in accordance with regulation 22.1 of this Annex may be taken as the attained EEXI if the value of the attained EEDI is equal to or less than that of the required EEXI as required by regulation 25 of this Annex. In this case, the attained EEXI shall be verified based on the EEDI technical file.

Two conditions. The ship is one to which regulation 22 applies, and the verified attained EEDI is equal to or less than the required EEXI. Where both hold, that EEDI value may be taken as the attained EEXI, and the verification then rests on the EEDI technical file.

The required EEXI applies a reduction factor to the reference line value

The required EEXI is the EEDI reference line value with a reduction factor applied, and the attained EEXI has to be at or below it. The reduction factor is given as a percentage and set by Table 3 by ship type and size band. The EEDI reference line value itself is calculated as regulation 24 provides.

Ship type	Size	Reduction factor
Bulk carrier	200,000 DWT and above	15
Bulk carrier	20,000 and above but less than 200,000 DWT	20
Bulk carrier	10,000 and above but less than 20,000 DWT	0-20
Gas carrier	15,000 DWT and above	30
Gas carrier	10,000 and above but less than 15,000 DWT	20
Gas carrier	2,000 and above but less than 10,000 DWT	0-20
Tanker	200,000 DWT and above	15
Tanker	20,000 and above but less than 200,000 DWT	20
Tanker	4,000 and above but less than 20,000 DWT	0-20
Containership	200,000 DWT and above	50
Containership	120,000 and above but less than 200,000 DWT	45
Containership	80,000 and above but less than 120,000 DWT	35
Containership	40,000 and above but less than 80,000 DWT	30
Containership	15,000 and above but less than 40,000 DWT	20
Containership	10,000 and above but less than 15,000 DWT	0-20
General cargo ship	15,000 DWT and above	30
General cargo ship	3,000 and above but less than 15,000 DWT	0-30
Refrigerated cargo carrier	5,000 DWT and above	15
Refrigerated cargo carrier	3,000 and above but less than 5,000 DWT	0-15
Combination carrier	20,000 DWT and above	20
Combination carrier	4,000 and above but less than 20,000 DWT	0-20
LNG carrier	10,000 DWT and above	30
Ro-ro cargo ship (vehicle carrier)	10,000 DWT and above	15
Ro-ro cargo ship	2,000 DWT and above	5
Ro-ro cargo ship	1,000 and above but less than 2,000 DWT	0-5
Ro-ro passenger ship	1,000 DWT and above	5
Ro-ro passenger ship	250 and above but less than 1,000 DWT	0-5
Cruise passenger ship having non-conventional propulsion	85,000 GT and above	30
Cruise passenger ship having non-conventional propulsion	25,000 and above but less than 85,000 GT	0-30

Check the interpolated factor before using the table

For a fictional 15,000 DWT bulk carrier, linear interpolation across the 10,000–20,000 DWT band from 0–20% gives a 10% reduction factor. Required EEXI is therefore 0.90 times the applicable EEDI reference-line value. This demonstrates the table, not verification of an actual ship.

The 2026-01-01 date in regulation 25 paragraph 3 is a review deadline; it does not automatically expire the table or change its values. Check the entry-into-force date and applicability of any adopted amendment separately.

Worth confirming

The passages above come from pages 35 and 40 of the 2021 revised MARPOL Annex VI (MEPC.328(76)). The table above reproduces Table 3; the EEDI reference line value and the interpolated result have to be calculated from that ship’s particulars. Which row of the table the ship falls in, whether it has undergone a major conversion, and whether the technical file shows the calculation process are where the actual judgement starts.

You can consult the cited source documents

These links lead to the official publishers of the documents discussed here. Match the edition and provisions cited in the article, and check subsequent amendments and flag-state implementation before applying them.

• IMO · MEPC.328(76)

Continue with the related operational guidance

• The three dates that decide EEDI application and the major conversion test (MARPOL Annex VI Regulation 19)