What is a Reference Material Definition of a national reference material

A reference material has one or more properties that are sufficiently uniform and well determined to calibrate equipment, evaluate measurement methods, or assign value to materials.

Note: Reference materials can be pure or mixed gases, liquids, or solids, such as pure water for calibrating viscometers. It is used as heat capacity in calorimetry.

The calibrator of the sapphire.

Solutions for chemical analysis calibration.

It can be used to directly prepare standard solutions or to calibrate the concentration of the solution in a titration analysis.

The concentration of the prepared solution, i.e., can be calculated directly.

Reagents that are not reference materials need to be titrated with a solution of the reference material after preparation to determine their concentration.

A substance or material that has been determined to have one or more sufficiently uniform characteristic values as a gage in the analytical measurement industryIt plays an indispensable role in the calibration of measuring instruments and devices, the evaluation of measurement and analysis methods, the measurement of the characteristic values of substances or materials, the assessment of the operational skill level of analysts, and the quality control of products in the production process.

For example, water for calibrating viscometers, sapphire for calorimetry as a calibrator for calorimetry, and solutions for chemical analysis calibration.

Reference material properties.

Accuracy, uniformity, and stability are the characteristics and basic requirements of the mass value of the standard.

1. Accuracy.

Usually, the reference material certificate will give both the standard value of the reference material and the uncertainty of the measurement, including weighing, instrument, uniformity, stability, uncertainty between different laboratories and different methods.

2. Uniformity.

Homogeneity is the state in which certain properties of a substance have the same composition or the same structure. The precision of the measurement method, i.e. the standard deviation, can be used to measure the uniformity of the reference material, the precision is affected by the sampling volume, the uniformity of the reference material is for the given sampling amount, and the minimum sampling amount for the uniformity test is generally given in the reference material certificate.

3. Stability.

Stability refers to the ability of a reference material to maintain its characteristic values within a specified range under specified environmental conditions and for a specified period of time.

We mainly use sodium thiosulfate, potassium hydroxide, etc. I think the so-called use of reference materials for testing is to make the values measured between industries have a unified reference standard, which is convenient for measuring the quality of substances!

There is still a difference between the reference material and the reference material, the purity of the reference material can be used as the benchmark of a certain determination method, used to prepare the calibration standard solution, with the reference material, the method is not necessarily reliable, it must be verified with the reference material, generally two different standard samples, and the nature of the sample to be tested is the same, or similar, according to the comparison between the measured value of the standard sample and the standard value, judge whether there is a problem with your own operation. If there is a systematic deviation, the possible causes need to be carefully analyzed, and if it cannot be overcome, it is necessary to calibrate the inspection system according to the standard sample.

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Reference materials and quasi-substances, also known as reference materials, are a class of materials or substances that are sufficiently homogeneous and have one (or more) characteristic values that determine the characteristics of the fibers, which are used to calibrate instruments and equipment, evaluate measurement methods, or assign values to other substances. Primary Reference Material: Stable, homogeneous, and highly accurate and reliable for the determination of several methods, which can be used to calibrate the decisive method and value the secondary reference material; Secondary Reference Material:

The first-class reference material is used to imitate the alumni, and the reference method is used to determine the value; Calibration: Calibrated with secondary reference material, the value is determined by conventional methods. For calibration of routine methods and instruments; ControlMaterial:

It has properties that are adapted to the assay process, and its composition is the same or similar to the matrix of the test sample.

A reference standard is defined as "a standard of measurement that generally has the highest metrological characteristics in a given area or within a given organization, from which the measurements made are derived".

Reference Material (RM): A substance or material that has been determined to have one or more characteristic values that are sufficiently uniform to act as a "gage" in the analytical measurement industry"It plays an indispensable role in the calibration of measuring instruments and devices, the evaluation of measurement and analysis methods, the measurement of the characteristic values of substances or materials, the assessment of the operational skill level of analysts, and the quality control of products in the production process.

Reference materials are measurement standards with accurate quantities, and they are widely used in chemical, biological, engineering, and physical measurements. Reference materials have the following characteristics:

1) The quantity value of the reference material is only related to the properties of the substance, and has nothing to do with the quantity and shape of the substance;

2) There are many types of reference materials, and there are thousands of chemical composition reference materials alone, and their limits span 12 orders of magnitude;

3) The reference material has strong practicability and can be applied under actual working conditions, which can be used for calibrating and verifying measuring instruments, evaluating the accuracy of measurement methods, and can also be used for quality evaluation of the measurement process and metrological certification and measurement arbitration of the laboratory;

4) Reference materials are reproducible and can be prepared in batches and replicated after use. In accordance with"The basic terminology of metrology is used internationally"with"ISO Guide 30"

Reference materials are defined as follows:

1) A reference material (RM) has one or more sufficiently uniform and well-defined characteristic values. A material or substance used to calibrate equipment, evaluate lateral measurement methods, or assign values to the feedstock.

2) Certified Reference Material (CRM) A certified reference material in which one or more characteristic values are determined using a process that establishes traceability so that it can be traced back to an exact reproduction of the unit of measurement used to express the characteristic value, and each standard value is accompanied by an uncertainty of a given confidence level. 3. Primary Reference Material (PRM) This is a relatively new concept, the International Committee for Weights and Measures (CIPM) established the Advisory Committee on Quality of Matter (CCQM) in 1993, and put forward the following definition at the meeting of the Advisory Committee on Quality of Substances in 1995; Primary Methed of Measurement (PMM) A measurement method of the highest metrological quality, whose operation can be fully described and understood, whose uncertainty can be expressed in Si units, and whose measurement results do not depend on the measurement standard being measured. Reference Standards:

A reference material with the highest metrological quality, whose value is determined by a reference method.

As can be seen from the above definition, reference materials have two distinctive characteristics:

1) Quantitative accuracy;

2) For metrological purposes. This clarifies some of the vague notions of reference materials that are not used to calibrate measuring instruments and measurement methods, and that do not require the accuracy of the measurements"Standard samples of the product range"(standard samples of cotton, grain, wool, linen and other products) are distinguished from reference materials.

Reference Material (RM).

A material or substance with one or more sufficiently uniform and well-determined characteristic values for calibrating equipment, evaluating measurement methods, or assigning value to materials.

Note: Reference materials can be made pure or mixed gases, liquids, or solids, such as pure water for calibration year, sapphire as a hot melt calibrator in calorimetry, and solutions for chemical analysis calibration.

Function: 1. Save and transmit characteristic quantities and establish measurement traceability.

The reference material is a measurement standard with accurate, uniform and stable characteristic values, which has the function of maintaining the characteristic values in time and transmitting the values in space. By using reference materials, the actual measurement results can be traced to the value of the measured value.

2. Ensure the consistency and comparability of measurement results.

By calibrating the measuring instrument and evaluating the measurement process, the reference material traces the measurement results to the International Unit (SI) system to ensure the consistency and comparability of the measurement results, so as to achieve the unity of the measurement value.

3. Research and evaluation of measurement methods.

Reference materials can be used as substances with known characteristic values to study and evaluate methods for measuring these components or properties. In order to judge the accuracy and repeatability of the method, and to evaluate the adaptability of the detection method in specific occasions by verifying and improving the accuracy of the measurement method, the development of calibration methods and testing techniques is promoted.

4. Ensure the smooth progress of product quality supervision and inspection.

In the production process, from the inspection of industrial raw materials, the control of technological processes, the evaluation of product quality, the trial production of new products to the treatment and utilization of three wastes, etc., a variety of corresponding reference materials are needed to ensure the reliability of the results, so that the production process is in a good state of quality control and effectively improve product quality. In addition, reference materials play an important role in the formulation, verification and implementation of product assurance, quality control and evaluation of product inspection and certification bodies, and user room accreditation.

The so-called standard is something that is used as a control, for example, to do acid-base titration, the acid is a standard, for example, to titrate the concentration of an unknown base, you can calculate the concentration of the unknown base by the volume of the two titrations.