Design Aspects of Blast Resistant Electrical Buildings

The design of three buildings, a control room, a large substation, and a medium substation are situated within a compression area for a natural gas facility. Owing to the close proximity of large gas compressors, these three buildings are designed to withstand blast forces from an accidental vapor cloud explosion. The control room is a single story building housing critical instrumentation controls and will be occupied continuously. The large substation and medium substation are two story buildings with the elevated floor housing critical electrical equipment and the lower floor provided for routing of connecting cables. This paper addresses topics pertaining to the rationale behind providing blast resistance, the determination of free field blast overpressure, structural engineering for blast resistance, and client-specific requirements. As applicable, topics are addressed with respect to the ASCE report Design of Blast Resistant Buildings in Petrochemical Facilities (ASCE 1997) and API Recommended Practice Management of Hazards Associated with Location of Process Plant Permanent Buildings (API RP752).