DOE (Department of Energy) capacity
4.2 cu ft, on the US site, is the DOE capacity, measured like this:
3.1.1 Place the clothes washer in such a position that the uppermost edge of the clothes container opening is leveled horizontally, so that the container will hold the maximum amount of water.
3.1.2 Line the inside of the clothes container with 2 mil (0.051 mm) plastic sheet. All clothes washer components which occupy space within the clothes container and which are recommended for use with the energy test cycle shall be in place and shall be lined with 2 mil (0.051 mm) plastic sheet to prevent water from entering any void space.
3.1.3 Record the total weight of the machine before adding water.
3.1.4 Fill the clothes container manually with either 60 °F±5 °F (15.6 °C±2.8 °C) or 100 °F±10 °F (37.8 °C±5.5 °C) water to its uppermost edge. Measure and record the weight of water, W, in pounds.
3.1.5 The clothes container capacity is calculated as follows:
C = W / d.
where:
C = Capacity in cubic feet (liters).
W = Mass of water in pounds (kilograms).
d = Density of water (62.0 lbs/ft3 for 100 °F (993 kg/m3 for 37.8 °C) or 62.3 lbs/ft3 for 60 °F (998 kg/m3 for 15.6 °C)).