Adequate blast resistant barriers are requisite to protect personnel and critical systems from the consequences of an accidental explosion and subsequent fire. Many of the blast walls currently installed in offshore structures were designed using simplified calculation approaches like Single Degree of Freedom models (SDOF) as recommended in many design guidelines. Over simplified and idealised explosion load used for response calculation and design of blast wall can lead to inadequate or overdesign of offshore blast walls. Due to lack of presence of a well-accepted design guidelines supported by extensive study, the protection provided by the conventional blast walls for offshore structures can be inadequate. In-depth understanding of structural response of blast walls under different blast loading can provide better design practice of blast walls for adequate protection. In this study, structural responses of conventional offshore blast walls were investigated. A computation fluid dynamics (CFD) approach was used to predict effect of different explosions on the barrier walls and non-linear finite elements analyses were performed to study the behaviour of the blast-loaded walls under different explosions. Effect of different parameters related to blast wall and accidental explosions were investigated to gain detail understanding of structural behaviour of typical steel blast wall.