External acts of interference towards industrial facilities have become a matter of increasing concern in recent years, especially in areas such as North Africa, where severe attacks to process facilities demonstrated the critical interface among integrated safety & security (ISS) aspects. The present work addressed this ISS concern and aimed at developing an interdisciplinary approach to support technical studies dedicated to the process industry. The first step consisted of a qualitative content analysis supporting the identification of critical ISS scenarios associated with process installations, as well as the critical socio-economic factors contributing to the terrorist threat. Next, the results of the qualitative analysis were implemented in a semi-quantitative methodology for the assessment of site attractiveness, with the aim of estimating the attack likelihood. Finally, the quantitative security risk assessment was carried out adopting: i) the attack likelihood estimated in the previous phase, and ii) a rigorous approach for the simulation of the dynamic evolution of ISS scenarios and related impact. For this purpose, the process simulator Honeywell UniSim® Design was used. The so evaluated accident impact and likelihood were combined using a risk matrix. The application to an industrial case study located in the Maghreb context was carried out in order to show the potentialities of the method and possible impact on the ISS enhancement of process industry.