[flyingtech55]

I have a feeling the 'installation height' is something to do with the Disability Discrimination Act (DDA). Baically the act states that wheelchair users must be able to reach sockets and light switches while using their wheelchairs. When 'my' building at the University was refurbished the requirements of the DDA had to be observed. Unfortunately this meant that the height of a light switch ended up below the height of a stand filing cabinet. This meant the already small tutors offices ended up even smaller because filing cabinets would no longer fit below light switches. They would only fit alongside so reducing the floor area. Happily the sockets were allowed to be fitted above desk height. I visited some sheltered housing recently and observed that the mains sockets were halfway up the walls for this very same reason.

TimR