The Brush > Surface sub-palette controls the way noise can be applied to the mesh surface.
The Noise button will allow you to assign noise to a sculpting brush using the settings in the NoiseMaker interface. The noise will be applied to your mesh as you sculpt.
To capture the greatest detail from Brush Noise subdivide your mesh.
Once noise has been assigned to the brush, the Edit button will enable you to make changes by re-launching the NoiseMaker interface.
The Del (Delete) button will remove the surface noise from the brush.
Reference Guide > Brush> Surface