This standard specifies the requirements and test methods for the use of intrinsically safe "i" protection for equipment in explosive environments. Intrinsically safe protection refers to technical measures that limit the energy of electrical equipment so that it cannot cause an explosion under normal and abnormal working conditions. The standard covers the basic requirements for the design, manufacture, installation and maintenance of equipment to ensure the safe use of equipment in potentially explosive environments. The standard is applicable to electrical equipment in various working environments and provides a technical basis for ensuring the safety of operation.