A review of explosion prevention and protection systems suitable as ultimate layer of protection in chemical process installations

Ideally, explosion risk is identified and prevented at an early stage of process design, forming a key part of the inherently safer design (ISD) approach. However, in practice, explosion risk often cannot be eliminated completely. Reliable preventive and protective systems must therefore be applied, as part of the now widely applied barrier or independent layer of protection approach (LOPA) to process design. Doing this requires a comprehensive knowledge of available systems. However, such a comprehensive overview of the various systems does not yet exist. This paper provides such an overview. The commercially available explosion prevention and mitigative systems applicable to gas, dust, mist and hybrid (gasaerosol) explosions are discussed, including basic principles and proper application for single and combined systems, for confined installations. Limitations of the applicability as well as limitations of the research-base of the various systems are also discussed.