Canada–Nova Scotia Offshore Area Petroleum Operations Framework Regulations — 133
Emergency shutdown system 133 (1) An operator must ensure that an installation has an emergency shutdown system that is capable of (a) shutting down all potential ignition sources and potential sources of flammable liquids or gases, including by isolating those sources; (b) depressurizing all potential sources of flammable liquids or gases other than reservoirs; (c) preventing abnormal conditions from escalating and causing major accidental events; and (d) limiting the extent and duration of any major accidental event. Studies and assessments — design (2) The operator must ensure that the design of the emergency shutdown system is based on studies, analyses and assessments that identify potential hazards and must assess the risks associated with those hazards, including the risk assessment conducted under subsection 107 (1) and the risk and reliability analysis referred to in section 108 . Design (3) The operator must ensure that the emergency shutdown system is designed to (a) allow for automated and manual activation to ensure effective shutdown; (b) allow for the shutdown of any system or equipment to bring it to a safe state, unless the system or equipment has been rated to remain operational in the area in which it is located, as that area is classified in accordance with the classification system referred to in subsection 113 (2); (c) allow for the selective shutdown of ventilation systems, other than fans that are necessary for supplying combustion air to engines that are required to operate during emergency situations unless gas has been detected in the intake to those engines; (d) allow for the isolation of petroleum and flammable fluid inventories, including reservoirs, wells, production systems and pipelines, from ignition sources; (e) take into account the size and segregation of petroleum and flammable fluid inventories to limit the quantity of substances released on loss of containment; (f) allow for the depressurization and the disposal of hydrocarbon inventories in a safe manner and to a safe location without cold venting; (g) allow for the closure of the installation’s subsea and subsurface safety valves and of pipeline safety valves; (h) take into account, in relation to all essential systems, the necessary timelines to support the safe escape, refuge and evacuation of persons and to maintain the integrity of the installation; and (i) take into account the activation of the fixed fire suppression systems required under paragraph 134 (4)(a). Shutdown logic (4) The operator must ensure that the logic for the emergency shutdown system includes a hierarchy of shutdown levels, action sequences and timelines that are appropriate for the degree of risk posed by the hazards identified in the studies, analyses and assessments referred to in subsection (2). Additional requirements (5) The operator must ensure, in relation to the emergency shutdown system, that (a) the system is reliable and, as far as is practicable, it is functionally and physically independent of other essential systems or, if that is not practicable, it is arranged so as not to adversely affect or be adversely affected by the operation of those systems; (b) the system includes an alarm system, with audible and visual alarms that are distinct from other types of alarms, that will automatically activate in the main control centre and at other strategic locations so that all affected persons, having regard to the hierarchy of shutdown levels referred to in subsection (4), are alerted to the emergency shutdown; (c) there is continuous monitoring from the main control centre of the system’s status, including, if the system or part of the system is overridden, the extent and duration of the override; (d) the system and its components are protected from mechanical damage and damage caused by fire, explosion and physical and environmental conditions to which they may be exposed so that they remain capable of fulfilling their intended functions under all for