Sony PCG-F540 Primary User Manual page 20

Clean the cabinet with a soft, dry cloth or a soft cloth lightly
moistened with a mild detergent solution. Do not use any type of
abrasive pad, scouring powder, or solvent such as alcohol or benzine,
as these may damage the finish of your computer.
Should any solid object or liquid fall into the computer, shut down
your computer and then unplug it. You may want to have the
computer checked by qualified personnel before operating it any
further.
Do not drop the computer or place heavy objects on top of the
computer.