Omron NSA Manual page 11

Symbols
Electrical Shock Caution
Indicates possibility of electric shock under
specific conditions.
General Prohibition
Indicates non-specific general prohibitions.
Disassembly Prohibition
Indicates prohibitions when there is a possibility
of injury, such as from electric shock, as the
result of disassembly.
Mandatory Action
Indicates a mandatory action with the specific
contents indicated in the circle and described in
the text.
General Caution
Indicates non-specific general cautions,
warnings, and dangers.
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