China: draft GB/T standard giving public measurement standards persistent CSTR identifiers to be cited in calibration certificates, among other documents
On 28 September 2026 China’s National Institute of Metrology (NIM) published for consultation the draft national standard GB/T “Specification for identification and coding of social public metrological standards information” (plan No. 20263291-T-469, committee SAC/TC 16). The draft, completed on 16 September 2026, sets out the code structure, its elements and rules of use.
- Under the draft, a social public measurement standard is a standard approved by the government metrology administration after assessment, serving as the basis for unifying quantity values in a region and having an attesting role in metrological supervision. The standard aims at unique, persistent identification of such standards to support dissemination of units, traceability and data exchange.
- The code builds on GB/T 32843-2016 on science and technology resource identifiers and takes the form CSTR:<registration agency code>.18.01.<holding institution>.<level>.<field>.<internal code>, where 18 denotes measurement standards and 01 public measurement standards; the length may not exceed 255 bytes. Example from the draft: CSTR:34923.18.01.NIM.N.M.2020360.
- The level is coded N, P, C and D (national, provincial, city, county — following the assessment system of JJF 1033-2023), and the field by 19 codes based on the first level of JJF 1022-2014, e.g. L – length, T – thermal, M – mechanical, E – electromagnetic, TF – time and frequency, IR – ionising radiation, PC – physical chemistry. The year plus the standard’s certificate number, e.g. 2020360, is recommended as the internal code.
- Institutions holding the standards are to maintain public information pages reached by resolving the identifier. Publications, reports and calibration certificates or verification documents that cite values derived from a given standard should give its identifier in a uniform citation form. NIM took part in drafting; the explanatory note and a comment form are attached to the consultation.