An innovative approach to hazardous area classification — Three dimensional (3D) modeling of hazardous areas

Abstract

This paper establishes an innovative approach to represent hazardous areas as true volumes in a plant 3D model and demonstrate increased safety. Examples from an Australian project have been used to compare the classical 2D vs innovative 3D approach. The 2D approach relies on plan and elevation drawings to show the hazardous areas from various sources of flammable release. Whereas, the 3D approach utilizes data rich 3D models used for the design of petrochemical plants. Industry standards (IEC, AS/NZS) require identification of all sources of release including piping (vents, flanges, etc.), identification of Electrical Equipment in Hazardous Areas (EEHA), preparation of Hazardous Area Verification Dossier (HAVD) and completion of detailed inspections. Such requirements may get adopted in North America as evidenced with the acceptance of IEC standards in Canada and Gulf of Mexico Offshore facilities [2][3]. The 3D approach automates the generation of EEHA list vs the error-prone manual identification using 2D layouts. The 3D approach allows capturing hazardous areas from piping sources, whereas, the 2D approach generally uses a note referencing a typical detail from a standard. The 2D approach requires man hour intensive physical walk downs and remedy of non-compliances during the construction phase. However, the 3D approach allows performing virtual walk downs of the facility to mitigate non-compliances during the detailed design phase, thus preventing schedule delays, design rework and replacement of equipment. The 3D approach presented sets an effective methodology for hazardous area classification thereby delivering safer petrochemical installations.