Separating earths at sockets

[Chunky]

Seem to recall being told but why do we separate earths at double sockets serving computer equipment.I seem to recall its to reduce static but what is the thinking behind it?
Cheers

 

[sparks1234]

Its to try to make sure we always have an earth, so if one side goes down theory says we have the other end of the ring

 

[nickblake]

Heres a post from sintra (sorry could get it to link sintra hope you dont mind me copying it)
Electricity Supply Regulation 26 indicates that the level of earth leakage current should not normally exceed one ten thousandth part of the installation maximum demand (for example, 10 mA earth leakage current for an installation with a maximum demand of 100 A). Data processing equipment is likely to have a higher leakage current than this, so special regulations become necessary. Foremost is the requirement that where earthing is used for functional purposes (to allow the filters to do their job) as well as protective purposes, the protective function must take precedence. When the earth leakage current is high, serious shocks are likely from accessible conductive parts which are connected to a protective conductor which is not itself solidly connected to the main earth terminal.
Any piece of equipment having a leakage current exceeding 3.5 mA must be fitted with a label adjacent to the primary power connection