A safety net assembly for selectively blocking and exposing an opening in a cargo container having a wall assembly bounding a storage space. A flexible net is selectively placed in: i) a first state wherein the net spans a substantial height and width of an access opening; and ii) a second state wherein the opening is further exposed. In the first state, the net has a first length between spaced first and second locations that spans a width portion of the opening along a horizontal line at a first height. The net is extensible to allow the first location on the net to be lowered while maintaining the second location on the net at the first height so that the line between the first and second locations is angled from horizontal and has a second length between the first and second locations that is greater than the first length.