Adds a measurement showing the minimum and maximum deviation between a mesh and a surface. This tool creates a locator showing the deviation between the two objects, labeling the minimum and maximum.
Objects in reference layers can be selected from within this tool.
Access this tool from the Locators palette:

Mesh to Surface Deviation Options
Check/uncheck the boxes to turn the labels and comb on or off.
The labels can also be toggled on/off from the Information Window.

When Show Comb is on, you can right-click a comb sample in the viewport to display the deviation value at that point. See Display deviation values in the viewport.