Clean rooms are essential element of any reputable data recovery company, but why is this?
A hard drive is an extremely delicate electronic component of a computer, and when it is manufactured or put together this has to be done in completely clean conditions. There must be no risk whatsoever of the platters or heads of a hard drive being contaminated by even the smallest speck of dust. Such contamination can cause data to be lost through corruption.
When a hard drive fails mechanically the data recovery company has to open up the hard drive, and this can only be done in perfectly clean conditions. A clean room is pressurized through fine filters so that when someone enters through an air lock, air will only flow out and not in.