The definition of
extreme states is
required to enable alerting before the
situation becomes
risky, and defining means to cope with the
potential
hazard. The definition of
extreme states is
required to enable alerting before the
situation becomes
risky, and defining means to cope with the
potential
hazard.
The definition of extreme states enables to check at run time whether the active state approaches the boundaries the design scope, in order to alert the operators about risky situations.
For each safety parameter we should specify two sets of
extreme states:
The operator might fail to recognize the source for the advance warning, or the
threat alert.
For each of the
extreme state, we should specify the best
system response in both types of
extreme states.
The
operator might not be aware of the
grace time,
before the hazard might materialize.
For each of safety parameter we should specify methods
for estimating the grace time, in order to display it to the
operators when in
risky situations.
The temperature of a boiler affects both the production and the safety. Two extreme states are associated with the boiler temperature, and may be defined as follows:
Updated on 12 Jun 2016.