GB/T 28020-2011Adornment - Determination of baneful elements - X-ray fluorescence spectrometric method (English PDF)

Foreword

This Standard was drafted in accordance with the rules given in GB/T 1.1-2009.

1 Scope

This standard specifies the X-ray fluorescence spectrometric detection method of baneful elements in adornment.

This standard applies to the detection of baneful elements in the surface layer of the adornment made in various materials (except jewelry and jade).

2 Normative References

The following documents are essential to the application of this document. For the dated documents, only the versions with the dates indicated are applicable to this document; for the undated documents, only the latest version (including all the amendments) are applicable to this standard.

GB 28480 Adornment - Provision for Limit of Baneful Elements

GB/T 28019 Adornment - Determination of Chromium (VI) - 1,5- Diphenylcarbohydrazide spectrophotometric method

3 Principle and Method

Principle of this method is as follows. surface layer of adornment can be excited by X- ray; it can emit characteristic X-ray. Energy of characteristic X-ray corresponds to each specific element.

4 Instruments and Apparatus

X-ray fluorescence spectrum analyzer Manganese is at the peak of 5.89 keV energy position, the resolution shall at least be 170 eV.

5 Test Methods and Requirements

6 Factors Affecting the Testing Results

- For the sample to be tested, there is plating on its surface OR its surface has been chemically treated;

- Detection time;

- Shape of the sample;

- Detection area for the sample;

- Degree of uniformity of the sample to be tested;

- Interference of the spectrum between the matrix and the baneful elements of the sample to be tested;

- Other influencing factors.

7 Determination of Results

7.1 As the decrease of the content (w) of the tested baneful elements, error of measurement result will increase. For the instrument, the higher of its detection limit (3 sigma) for harmful elements, the greater the error of measurement result will be.

7.3 In light of that most of the adornments have the characteristics of metal, for the analytical correction coefficients of baneful elements' maximum limit, it is recommended to choose 30%. Therefore. […]