This document specifies the terms and definitions, classification and nomenclature, technical requirements, test methods, inspection rules and markings, packaging, transportation and storage of instant electric water heaters. This document is applicable to conventional non-intelligent instant electric water heaters for household and similar purposes where the water source is domestic water required by GB5749, the rated voltage of single-phase appliances does not exceed 250V, and the rated voltage of other appliances does not exceed 480V. This document does not apply to storage water heaters.