The key element of the Occupational Health and Safety Management System Specification (GB T28001-2011) is ().

Answer: a, c, d, e

The standard structure system adopts PDCA circulation management mode, that is, the standard consists of five elements: "occupational health and safety policy-planning-implementation and operation-inspection and corrective measures-management review", and adopts PDCA dynamic circulation and upward spiral operation mode, which embodies the dynamic management idea of continuous improvement.