ADA boilerplate:
http://www.access-board.gov/adaag/html/adaag.htm 4.2.5* Forward Reach. If the clear floor space only allows forward approach to an object, the maximum high forward reach allowed shall be 48 in (1220 mm) (see Fig. 5(a)). The minimum low forward reach is 15 in (380 mm). If the high forward reach is over an obstruction, reach and clearances shall be as shown in Fig. 5(b). Appendix Note
This is the phrasing that limits switch box heights and forces receptacles up from the floor.
Hence the California Title 24 specifications that boxes be set at 46” AFF ( switches ) and 18” AFF ( receptacles ).
GFCI receptacles within bathrooms are typically set at 42” or 44” AFF... Back splashes and sinks being slightly higher in commercial.