SCE group PC004 SCE group title Tanks Tank envelope including the liquid and vapour spaces. To maintain leak tight integrity. Hydrocarbon or hazardous material process tanks in the following services oil production, processing, handling and export condensate processing, handling and export flammable or hazardous chemicals crude oil storage diesel tanks At item level, i.e. per tank SCE group PC005 SCE group title Piping Systems Piping systems. To maintain the integrity of pipework including instrument tubing and flexible hoses which contain flammable, or explosive liquid or gas. Piping systems containing flammable or hazardous fluids under pressure within and between operating units within and between modules At subsystem level