A fully loaded bulk carrier was proceeding at full sea speed on a south westerly course in the Mediterranean Sea in conditions of heavy weather. The bosun and a cadet were instructed to wash down the vessel’s main deck and hatch covers to remove grain cargo dust remaining from the previous loading operations. At this time, the wind was blowing from a south easterly direction at about 30 knots, equivalent to force 7 on the Beaufort wind scale. While the seamen were working on the port side, a large wave was shipped on deck, sweeping them heavily against the adjacent cargo hold hatch coamings. Both seamen sustained multiple injuries requiring the vessel to deviate from the planned route to land them ashore for urgent medical treatment.