A very great advantage of icon-based interfaces for industrial workers is the potential
to convey messages free from the constraints of language. Signs and icons can also be
used to convey information to people who cannot read printed messages because of
vision problems, low-level verbal skills, or inadequate knowledge of the language used
in the warning. However, in practice, such icon-based graphical signs may not always
be effective and it has been suggested that poorly designed symbols can lead to injury
due to the lack of understanding or misinterpretation (Raskin, 2000).