Quantitative/semi-quantitative explosion risk assessment methods are used for evaluation purposes [e.g. 2]. These methods are based on the estimation of explosion risk based on the frequency of occurrence of sources of ignition and possible effects of an explosion. The paper presents a novel approach to the assessment of explosion risk, which emphasizes process conditions (unit operations, construction and working conditions of equipment as well as the physical properties of the substances used). This enables the determination of the level of risks resulting from the process. Potential ignition sources are identified in the next step. These are then related to the estimated level of risk associated with the analysed unit processes. This is the final prerequisite for deciding whether or not to apply protection of the process units against effects of an explosion.
