Definition of first-level reference materials and country 2
first-class reference materialIt refers to the absolute measurement method or other accurate and reliable methods to determine the material characteristic quantity, the accuracy reaches the highest level in China, and the uniformity is within the accuracy range; the stability is more than one year, or it reaches the advanced level of similar reference materials in the world, and it is issued with a certificate after the technical review of the Standard Materials Professional Committee of the China Metrology and Testing Society and the approval of the State Metrology Bureau.
(A) Valuation by absolute measurement or by two or more accurate and reliable methods of different principles
In the case of multiple laboratories, the same accurate and reliable method is used to determine the value.
(B) The accuracy is at the highest level in the country, and the uniformity is within the accuracy range.
(C) Stability for more than one year, or reaching the international advanced level of similar reference materials;
(D) The packaging form meets the requirements of the technical specification for reference materials.
Secondary reference materials meet the following conditions:
(A) Valuation by the method of comparing the quantity with the first-level reference substance or the method of setting the value of the first-level reference substance.
(B) the accuracy and uniformity do not reach the level of first-class reference materials, but can meet the needs of general measurement.
(C) The stability is more than half a year, or it can meet the needs of actual children.
(D) The packaging form meets the requirements of the technical specification for reference materials.
(3) Reference material number
The number of the first-class standard substance is preceded by the standard substance code "GBW", and the first two digits of the number are the standard.
The major class number of the substance. The third digit is the minor class number of the reference substance, and the last two digits are the sequence number. The production batch number is in English lowercase
The mother denotes. Ranked in the last digit of the reference substance number.
The number of the first-class reference material isGBWMainly, the number of the second-level reference substance is the code of the second-level reference substance "GBW(E)"Crown in the front of the number, the first two digits of the number are the large category number of the reference material, the last four digits are the sequence number, and the production batch number is represented by English lowercase letters, ranking in the last digit of the number.
