Four weeks is probably a severe test for any reaonably small PSK. However, circumstances could vary the experience tremendously. For example, I could easily make it for a month in the Channel Islands, just living on tide pool critters. Since I would be active in aiding searchers - signal mirror and marker panels by day and a pillar of fire by night, unless the searchers are looking in a completely erroneous area, the search ain't gonna last more than a few days. <br><br>There is a record of a lady surviving on Anacapa Island for fourteen days following the sinking of her vessel (her two male companions perished in the sinking) in 1946. She stayed in a fisherman's shack on the island - probably didn't have either a PSK or an Altiods tin.<br><br>Historical records indicate that willpower and simople will to survive are really important. There are many of records of survivors who shouldn't have made it according to accepted guidelines. It is the person who survives or dies, not the PSK.