There are two kinds of standard numbers: international standard number and Chinese national standard number.
International standard number and foreign standard number have different forms, but the basic structure is as follows.
Standard code+professional classification number+serial number+year number.
Among them, most standard codes use abbreviations, such as IEC for International Electrotechnical Commission, API for american petroleum institute, ASTM for American Society for Testing and Materials, etc.
Professional category numbers vary with different classification methods, and there are three forms: letters, numbers and mixed letters and numbers; The form of serial number and year number in standard number is basically the same as that in China. The ISO code number and mixed format of international standards are ISO+ standard number+[column+sub-standard number]+colon+release year number (the contents in brackets are optional), such as ISO 8402: 1987 and ISO 9000- 1: 1994 are ISO standard numbers respectively.