They cannot be installed face up in countertops or similar areas
406.5(E) Receptacles in Countertops and SimilarWork Surfaces.
Receptacles, unless listed as receptacle assemblies
for countertop applications, shall not be installed in a
face-up position in countertops or similar work surfaces
Depends upon your Code cycle. As Dennis noted, Section 406.5(E) has a general prohibition of face up receptacles in countertops and similar work surfaces.
In 2011, however, the prohibition was only for Dwelling Units.