A significant feature of critical systems such as power plants is their control by human operators. For that, they are placed at the field level where they perceive, process and provide the necessary information, which is partially digitalized. Another significant feature of the engineering of these systems is to focus mainly on technical requirements that are further checked by human factors and ergonomics specialists. Improving the co-specification process of these systems as a whole requires providing measurable requirements in order to bring together human and technical aspects of these systems. The resulting issue is to check the balance between the two types of specifications from an early project stage. In that way, we propose a system co-specification framework based on an integrative construct enabling to check the compliance of system requirements with automation and physiological requirements by coexecution of models. This framework is applied on a case-study in order to propose physicalphysiological pre-requirements of a sound perception artefact by a field operator. These exploratory works aim to contribute to Model-Based Human-System Integration.