Safety Critical Element Management Manual EP 2009-9009 Restricted 40 SCE group listing (continued) SCE goal Typical equipment types Description Minimum level SCE group PC007 SCE group title Relief System Relief systems designed to protect pressure containing equipment and piping from over or under pressurisation. To prevent a loss of containment of process fluids in upset conditions and the controlled disposal of hydrocarbon fluids Safety relief valve Pressure Vacuum Valve Associated relief pipework At item level, i.e. per relief valve SCE group PC008 SCE group title Operational Well Containment Well containment covers all components that provide an envelope for containment of well pressure. To contain hydrocarbons and other hazardous substances, and to isolate the well in response to an upset/abnormal event. Well containment systems for onshore oil production and gas injection wells offshore oil production and gas injection wells remote subsea production wells. At item level, i.e. per well