This International Standard specifies a uniform method for calculating the average ground contact pressure of self-propelled and towed crawler (track-laying) earth-moving machines, as defined in ISO 6165, on soft surfaces with empty equipment or attachment. The average ground contact pressure value is used only for comparing different machine models. Actual ground contact pressure values under operating conditions will vary depending on load, position of the centre of gravity, terrain, track shoe type and size, and surface conditions. NOTE 1 Alternative methods for determining ground contact pressure could apply to some specific machine families. NOTE 2 The calculation makes allowance for some penetration into the supporting soil surface and the resulting increase in support area.