This standard specifies the terms and definitions, classification, basic requirements, technical requirements and test methods, inspection rules, and markings of non-dispersion shifted single-mode optical fiber preforms (referred to as B1.3 optical fiber preforms) with B1.3 wavelength band extension for communications. , packaging, transportation, storage and quality commitment. This standard applies to non-dispersion-shifted single-mode optical fiber preforms with extended B1.3 wavelength range for communications in which the core layer and cladding layer are fused into one.