Imagine a box that is 36" deep from the front of the panelboard out, and 30 inches wide, but does not have to be centered on the panel, just that it include all of the panel width, and that the box is 2 meters high (about 6 ft 6 in). That is the area that has to be free and clear of obstructions (though its perfectly OK if a door swings over the front of the panel, if it can be moved out of the way to access the panel.
Distance requirements from sinks are in relation to electric receptacles. If located within a specified distance of the sink, tub, etc, then they have to be GFCI.
Charles