The personnel model in ISA-95 is an abstract model that allows the definition of person and roles that individual persons can be assigned to PersonnelClasses (see Figure 22). The requirements associated with a given role may include specific training or certification. It may be related to Job Titles or skills. A single person may be associated with multiple roles. Persons may be grouped into a type of Person, to allow properties to be associated with all persons that fall into the given type. For example a Person Type of Operator type may allow, multiple operators to have the same defined qualification tests, some of which are defined by the operator role, others may be defined by safety role or a role for a specific type of equipment.
Figure 23 illustrates personnel model which consists of specific person, ISA95Classes of personnel, and qualification of personnel. It includes an example subtype that illustrates creating customized sub type of PersonnelClass. The illustration further illustrates creating actual instance of the individual types and how multiple classes can be combined into a single instance. This figure does not illustrate how a subtype of PersonType can be created and used to classify multiple persons as being of the same type. The concept of a sub type of PersonType is allowed, but since most persons would have unique training and classification in many cases subtypes of PersonType would not exist.