Canon pmn Advanced User's Manual page 12

When not using the camera for extended periods of time,
remove the batteries from the camera or battery charger
and store the equipment in a safe place.
If the batteries are left inside the camera, damage caused by
leakage may occur.
Do not connect compact power adapters or battery
chargers to devices such as electrical transformers for
foreign travel because it may lead to malfunctions,
excessive heat generation, fire, electric shock or injury.
Do not operate the flash with dirt, dust or other items stuck
to the surface of the flash.
Be careful not to cover the flash with your fingers or
clothing when shooting.
The flash may be damaged and emit smoke or noise. The resulting
heat build-up could damage the flash.
Do not touch the surface of the flash after taking several
pictures in rapid succession.
Doing so could result in burns.
10
Equipment
Flash