Deck Wetness - Freeboard Exceedance
Probability of bow freeboard exceedance (deck wetness) per wave encounter using the Rayleigh distribution and motion σ.
Deck-wetness probability
0.1271 -
Formula, assumptions, and limits
$$P_{wet} = \exp(-F_B^2 / 2\sigma_z^2)$$
Rayleigh-distributed assumption. NORDFORSK criteria keeps $P_{\text{wet}}$ ≤ 0.05 for cargo ships in 7 m $H_s$ for operational limit. Greater values indicate need for flare / bulwark.
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $F_B$ | Bow freeboard | m | GA / load-line mark |
| $\sigma_z$ | σ bow relative motion | m | strip theory |
Spotted an error in this calculation? . We acknowledge editorial corrections within two working days.