Apple iMac (21.5-inch and 27-inch, Mid 2011) - Manual (Page 66)

66 Chapter 5 Last, but Not Least
For your safety and that of your equipment, follow these rules for handling and
cleaning your iMac and for working more comfortably. Keep these instructions handy
for reference by you and others.
NOTICE: Incorrect storage or use of your computer may void the manufacturer’s
warranty.
Important Safety Information
WARNING: Failure to follow these safety instructions could result in fire, electric
shock, or other injury or damage.
Proper handling Set up your iMac on a stable work surface. Never push objects into
the ventilation openings.
Water and wet locations Keep your iMac away from sources of liquid, such as drinks,
washbasins, bathtubs, shower stalls, and so on. Protect your iMac from dampness or
wet weather, such as rain, snow, and fog.
Power The only way to disconnect power completely is to unplug the power cord.
Make sure you pull the plug, not the cord. Always unplug the power cord before
opening your iMac to install memory.