PRS revises slamming rules

Following research that showed that bow slamming in moderate sea states can be as damaging as those in bad weather, Polish classification society, Polski Rejestr Statkow (PRS), has revised its rules. The horizontal forces caused by the bow driving into the wave crests are larger in moderate seas than vertical loads caused by wave action.

Against older tonnage, modern ships have large flare angles in the bow area and travel faster ? both factors increasing the severity of bow slamming. Although ships slow down during bad weather they usually maintain speed in moderate conditions which can lead to very high forces acting on the hull.

The new rules ensure that both conditions are taken into account. It is also proposing that bow visor securing systems should be based on the ultimate strength concept, rather than a linear response to impact loads.