EEDI Reference Line

Look up the baseline reference line for any ship type - a × Capacity^(−c) per MEPC.231(65)/328(76). Applies to EEDI and EEXI attained/required calculations.

IMODesignReference line

Ship typeCapacityDWT

Reference line

4.357gCO₂ / t·nm

961.79 × Capacity^(−0.477)

Coefficient a

961.79

Exponent c

0.477

Formula, assumptions, and limits

Reference = a × Capacity^(−c)

Coefficients from MEPC.231(65) as amended by MEPC.328(76). A bulk carrier with a = 961.79, c = 0.477 at 82,000 DWT has a reference of ~4.36 gCO₂/(t·nm). Multiply by (1 − Z) to get Required EEDI for that ship's phase and size band.