Design scope. The specifications should include a definition of its
boundaries. Within these boundaries, the specification of
the system behavior should be complete.
Prohibit
errors. The design should not be tolerant to any
human errors. The design should assume the Human Factors variant of
Murphy's law:
If the
system enables the
operators to fail, eventually they will!
Usability. The
interaction will be designed based on
models of the
user's and operator's behavior, to ensure that they understand its
procedures and behavior.
Situation awareness. The design should be based on the premise that
the operator cannot trace the
machine modes reliably. It is the
designer's responsibility to ensure that the
operators are always aware
of the system situation.
Workload reduction. The design should consider
human factors, including the
operators' main
tasks, including those that are not related to the
systemoperation. To
prevent distraction, the design should reduce the mental load required
for the system operation.
Defend against mistakes. The probability of users' and operators' mistakes in exceptional states is high. The design should mitigating the
risks of design
mistakes, such as by reducing the
systemcomplexity (principle of
parsimony).