washing operation and a horizontal open position for loading and unloading of articles from the dishwasher latch 123 is used to lock and unlock door 120 for access to chamber 106 upper and lower guide rails 124 126 are mounted on tub side walls 128 and accommodate roller equipped rack assemblies 130 and 132 each of the rack assemblies 130 132 is fabricated into lattice structures including a plurality of elongated members 134 for clarity of illustration not all elongated members making up assemblies 130 and 132 are shown in fig2 each rack 130 132 is adapted for movement between an extended loading position not shown in which the rack is substantially positioned outside the wash chamber 106 and a retracted position shown in fig1 and 2 in which the rack is located inside the wash chamber 106 this is facilitated by rollers 135 and 139 for example mounted onto racks 130 and 132 respectively a silverware basket not shown may be removably attached to rack assembly 132 for placement of silverware utensils and the like that are otherwise too small to be accommodated by the racks 130 132 the dishwasher 100 further includes a lower spray arm assembly 144 that is rotatably mounted within a lower region 146 of the wash chamber 106 and above a tub sump portion 142 so as to rotate in relatively close proximity to rack assembly 132 a mid level spray arm assembly 148 is located in an upper region of the wash chamber 106 and may be located in close proximity to upper rack 130 additionally an upper spray assembly 150 may be located above the upper rack 130.