Fujitsu fi-4220C Operator's Manual page 19

The following describes important cautions described in this
manual.
Do not touch the AC cable with wet hands.
Do not install the scanner on unstable surfaces.
Firmly insert the power plug.
xviii
Do not insert or disconnect the power plug with wet
hands. Doing so might cause electric shock.
Install the scanner on a desk so that none of its parts
protrude outside of the desktop. Also, make sure that
the scanner is installed on a flat, level surface.
Do not install the scanner on unstable surfaces.
Install the scanner on a level surface that is free of
vibration to prevent it from tilting.
Firmly insert the power plug into the power outlet as
far it can go.