There is a section on the computation of freeboards, including special requirements for ships assigned timber freeboards, in particular methods of stowage and securing of deck cargoes.
The zones, areas and seasonal periods are defined, together with any applicable dates or relevant ship size.These are:
—Northern Winter Seasonal Zones and Area. —North Atlantic Winter Seasonal Area. —North Pacific Winter Seasonal Zone. —Southern Winter Seasonal Zone. —Tropical Zone. —Seasonal Tropical Areas. —Summer Zones.