When constructing a scaffold, there are specific criteria for the foundation or base on which the scaffold is built. This foundation must be firm, stable, and capable of supporting the scaffold's load without settling or shifting. Commonly, scaffold poles, legs, and frames must bear on base plates and mud sills or other equivalent firm foundations. The foundation should be level, sound, and rigid, preventing the scaffold from settling into the ground. Examples of adequate foundations include flat, level concrete slabs, compacted soil that is stable, and firm footing materials that evenly distribute the scaffold's load to the ground. A competent person should inspect and approve the foundation daily to ensure ongoing stability and safety during use.