GB/T 21187-2026Atomic absorption spectrophotometers (English PDF)

4.2 Safety Requirements

4.2.1 Contact Current The contact current should meet the following requirements.

a) Under normal operating conditions, the instrument's contact current should not exceed

0.5 mA (RMS) or

0.7 mA (peak-to-peak).

b) Under single fault conditions, the contact current of the instrument shall not exceed 3.5mA (RMS) or 5mA (peak-to-peak).

4.2.2 Dielectric strength Under normal operating conditions, the instrument should withstand a continuous voltage test of 1500V AC RMS for 1 minute without arcing or breakdown. Phenomenon.

4.2.3 Protective grounding The impedance between the grounding protection terminal and each accessible component with a protected connection should not exceed 0.1Omega, excluding the power cord. impedance.

4.2.4 Safety of Flame Atomization Systems The flame atomization system should have accurate and reliable gas path protection and flame monitoring functions, and should automatically shut off in the event of flame extinguishing. The gas supply will automatically trigger an alarm or notification.

4.2.5 Flame gas path system sealing performance Under normal operating pressure and closed conditions, the pressure drop of the combustion gas system should not exceed [a certain value] within 15 minutes. The pressure drop in the gas system should not exceed

0.005 MPa, with a pressure drop of

0.01 MPa.

4.2.6 Safety signs Instrument atomization systems containing high-temperature components and electrical systems containing high-voltage components should have clearly visible safety signs warning of the corresponding risks. The risk level should comply with the requirements of GB 4793.1-2007.

4.3 Wavelength indication error and wavelength repeatability The instrument's wavelength indication error and wavelength repeatability should meet the requirements of Table 1.

4.4 resolution When using a spectral bandwidth of

4.5 Baseline stability

4.5.1 Fire Magic The baseline stability of the instrument should meet the requirements of Table 2.

4.5.2 Graphite Furnace Process The baseline stability of the instrument should meet the requirements of Table 3.

4.6 Measurement Sensitivity

4.6.1 Fire Magic Depending on the type of instrument, one of the following requirements should be met.

a) Non-Zehnder type instrument. When measuring a copper element calibration solution with a mass concentration of 2.00 µg/mL, the absorbance value should not be less than 0.2;

b) Zeeman type instrument. for measuring copper element calibration solution with a mass concentration of 2.00 µg/mL, the absorbance value is not less than 0.1.

4.6.2 Graphite Furnace Process Depending on the type of instrument, one of the following requirements should be met.

a) Non-Zeeman type instrument. Measure the absorbance of a cadmium calibration solution with a mass concentration of

1.00 ng/mL and an injection volume of 20 µL. The absorbance value should be not less than 0.1, or the absorbance value should be not less than

0.05 when the injection volume is 10 µL;

b) Zeeman type instrument. Measure the absorbance of a cadmium calibration solution with a mass concentration of

1.00 ng/mL and an injection volume of 20 µL. The absorbance value is not less than 0.08, or the absorbance value is not less than

0.04 when the injection volume is 10 µL.

4.7 Limit of Detection

4.7.1 Fire Magic Depending on the type of instrument, one of the following requirements should be met.

a) Non-Zehnder type instruments. The detection limit for measuring copper calibration solution is no greater than 0.004 µg/mL;

b) Zeeman type instrument. The detection limit for measuring copper element calibration solution is not greater than 0.005 µg/mL.

4.7.2 Graphite Furnace Process Depending on the type of instrument, one of the following requirements should be met.

a) Non-Zehnderm type instruments. The detection limit for measuring cadmium in calibration solutions is no greater than 2 pg;

b) Zeeman type instrument. The detection limit for measuring cadmium in calibration solution is no greater than

4.8 Repeatability

4.8.1 Fire Magic The repeatability of measuring the copper element calibration solution should be no greater than 1%.

4.8.2 Graphite Furnace Process The repeatability of the cadmium calibration solution should be no greater than 3%.

4.9 Absorbance indication error The instrument absorbance reading error should meet the requirements of Table 4.

4.10 Edge Wavelength Noise The instantaneous noise absorbance values for arsenic and cesium measurements should meet the requirements of Table 5.

4.11 Background Correction Capability

4.11.1 Deuterium lamp background correction method The background absorbance value should be between

0.9 and 1.1, and the correction capability should be no less than 30 times.

4.11.2 Self-absorption background correction method The self-absorption background correction capability should meet the requirements of Table 6.

4.12 Slit shifting positioning error The wavelength error caused by slit shifting should not exceed

0.3 nm.

4.13 Stability After the instrument has been running for 2 hours, it should meet the requirements of 4.5.

4.14 Instrument Appearance It should comply with the requirements of section

5.2 of GB/T 12519-2021.

4.15 Instrument completeness It should comply with the requirements of

5.10 in GB/T 12519-2021.

4.16 Environmental adaptability

4.16.1 Power supply environment adaptability When the power supply voltage is (220±22)V and the frequency is (50±1)Hz, it should meet the requirements of 4.5.

4.16.2 Climate and Environmental Adaptability

4.16.2.1 Low Temperature Test After the ambient temperature is maintained at 15°C for 4 hours, it should meet the requirements of 4.5.

4.16.2.2 High Temperature Test After the ambient temperature is maintained at 35°C for 4 hours, it should meet the requirements of 4.5.

4.17 Electromagnetic Compatibility Class I instruments should conform to the basic requirements for electrostatic discharge (ESD), radio frequency electromagnetic fields, pulse bursts, and surges in Table 1 of GB/T 18268.1-2025. Require.

5.1 Test conditions, equipment and reagents

5.1.1 Test Conditions The instrument should be preheated for 30 minutes before the test, and the test should be conducted under the conditions in 4.1.

5.1.2 Test Equipment and Auxiliary Materials The following equipment and auxiliary materials are used during instrument testing.

a) Hollow cathode lamps. single-element hollow cathode lamps containing mercury, manganese, copper, cadmium, arsenic, and cesium;

b) Visible filters. 1 set, with certified standard materials or visible light transmittance filters with nominal transmittance values of 10%, 20%, and 30% respectively. The transmittance uncertainty of the optical sheet (with a fixed wavelength including 546.0 nm) is no greater than 0.5%.

c) Ultraviolet filters. 2 filters, with a nominal transmittance of 10% ± 1% in the ultraviolet region (the specified wavelength should include...). (at 228.8nm)

d) Stopwatch. graduation value not greater than 0.1s;

e) Pressure gauge. accuracy class <= 1.6, measuring range (0~0.25) MPa or (0~0.4) MPa;

f) Light-blocking plate, soapy water, switch valve, pipe plug;

g) Leakage current tester, withstand voltage tester, and grounding continuity resistance tester;

h) Automatic sampler or micropipette;

i) Air from an air compressor or gas cylinder;

j) Cooling water circulating machine or cooling water source;

k) Analytical acetylene gas with a purity of not less than 99%;

l) Argon gas with a purity of not less than 99.99%;

5.2 Safety Requirements

5.2.1 Contact Current The test shall be conducted in accordance with the relevant provisions of section

6.2 of GB/T 34065-2017.

5.2.2 Dielectric Strength The test shall be conducted in accordance with the relevant provisions of section

6.3 of GB/T 34065-2017.

5.2.3 Protective grounding The test shall be conducted in accordance with the relevant provisions of section

6.4 of GB/T 34065-2017.

5.2.4 Safety of Flame Atomization Systems After igniting the flame according to the instrument's ignition operating procedures, quickly insert a light-blocking plate between the flame sensor and the flame, and then check whether the instrument can... Automatically cut off the gas supply and observe for any automatic alarms or prompts. With the flame ignited, apply soapy water to the atomization chamber to check for leaks.

5.2.5 Flame gas path system sealing performance Connect the compressed air source, pressure gauge, and switch valve to the inlet of the combustion-supporting gas or gas circuit system, and seal the gas outlet using pipe plugs or similar plugs. After the pressure in the combustion-supporting gas system rises to

0.2 MPa and the pressure in the gas system rises to

0.05 MPa, shut off the gas supply. Use a pressure gauge to check the pressure at each stage. The pressure drop value of the gas-supporting system and the gas system at the pressure gauge within 15 minutes.

5.2.6 Safety signs Visual inspection.

5.3 Wavelength indication error and wavelength repeatability Install and turn on a hollow cathode lamp for mercury, setting the spectral bandwidth to

0.2 nm, at 253.65 nm, 365.02 nm, and 435.83 nm. From the spectral lines at 546.07 nm, 730.03 nm, and 871.66 nm, select 3 to 5 spectral lines that are roughly evenly distributed from short wave to long wave, and perform single-wavelength analysis. Three measurements were taken, and the wavelength values at which the energy of each spectral line reached its peak were read. Calculate the wavelength indication error of each spectral line according to formula (1), and take the one with the largest absolute value as the wavelength indication error of the instrument. The wavelength repeatability of each spectral line is calculated according to formula (2), and the maximum value is taken as the wavelength repeatability of the instrument.

5.4 resolution Install and turn on the copper hollow cathode lamp, select the 324.75nm spectral line for copper, set the spectral bandwidth to 0.2nm, and adjust the corresponding detection system. The parameters are set so that the peak energy of the spectral line is 100% ± 1%. First, the wavelength of the peak spectral line is scanned, then the range of ±

5.5 Baseline stability

5.5.1 Fire Magic Install and turn on the copper hollow cathode lamp, select the 324.75nm spectral line of copper, set the spectral bandwidth to 0.2nm, and set the time constant to be small. Continuous measurement method with a duration of

0.5 seconds. The hollow cathode lamp is preheated for 30 minutes, then the flame is ignited, and all other parameters are adjusted to the optimal operating condition for the flame method. The absorbance was zeroed with water and recorded for 15 consecutive minutes. As shown in Figure 2, the difference between the maximum and minimum values of the center line of the baseline spectrum envelope is the baseline drift, and the maximum instantaneous peak-to-peak value is... Baseline transient noise.

5.5.2 Graphite Furnace Process Install and turn on the copper hollow cathode lamp, select the 324.75nm spectral line of copper, set the spectral bandwidth to 0.2nm, and set the time constant to be small. The measurement was performed continuously for

0.5 seconds. The hollow cathode lamp was preheated for 30 minutes, and the absorbance values were recorded continuously for 15 minutes. As shown in Figure 2, baseline drift and baseline instantaneous noise are read out.

Note. Instruments without graphite furnace atomization capabilities are not eligible for this experiment.

5.6 Measurement Sensitivity

5.6.1 Fire Magic Install and light the copper hollow cathode lamp, select the 324.75nm spectral line for copper, set the spectral bandwidth to 0.2nm, ignite the flame, and then... Adjust all parameters to the optimal operating condition for the flame method. Zero the instrument with water, and take the average of three consecutive absorbance measurements on the blank calibration solution. For copper... The absorbance of the elemental calibration solution was measured seven times consecutively, and the average value was taken. Calculate the measurement sensitivity using formula (4).

5.6.2 Graphite Furnace Process Install and turn on the cadmium hollow cathode lamp, select the cadmium 228.80nm spectral line, set the spectral bandwidth to 0.2nm, and adjust all other parameters to [unspecified values]. Optimal operating conditions for the graphite furnace chromatography method. Use an autosampler or micropipette to set the injection volume to 20 µL or 10 µL, and perform blank calibration. The absorbance of the standard solution was measured three times consecutively and the average value was taken. The absorbance of the cadmium element calibration solution was measured seven times consecutively and the average value was taken. Calculate the measurement sensitivity using formula (4).

Note. Instruments without graphite furnace atomization capabilities are not eligible for this experiment.

5.7 Limit of Detection

5.7.1 Fire Magic The instrument conditions are the same as in 5.6.1.The absorbance values of the blank calibration solution are measured 11 times consecutively. Calculate the standard deviation using formula (5); calculate the standard deviation using formula (6) based on the average absorbance measured with the copper element calibration solution in 5.6.1. Detection limit.

5.11.3 Zeeman Background Correction Method

5.11.3.1 Fire Magic Install and turn on the cadmium hollow cathode lamp, select the cadmium 228.80nm spectral line, set the spectral bandwidth to 0.2mm, and set the instrument to background. Calibrate the operating status and adjust all other parameters to the optimal operating condition for flame spectroscopy. Depending on the instrument's classification performance, select one or two UV-C filters. Insert a filter into the optical path to produce an absorbance value that meets the requirements of 4.11.3, and read the absorbance value A1 without background correction and the absorbance value with background correction. The absorbance value A2 is used to calculate the background correction capability, and the A1/A2 value is calculated.

Note. Instruments without flame atomization or Zeeman background correction functions should not be used for this experiment.

5.11.3.2 Graphite Furnace Process Install and turn on the cadmium hollow cathode lamp, select the cadmium 228.80nm spectral line, set the spectral bandwidth to 0.2mm, and set the instrument to background. Calibrate the operating conditions and adjust all other parameters to the optimal operating state for the graphite furnace method. Inject an appropriate volume using an autosampler or micropipette. The sodium chloride calibration solution was used to generate absorbance values that met the requirements of 4.11.3.The absorbance value A1 without background correction and the background correction value were then read. The absorbance value A2 is used to calculate the background correction capability, and the A1/A2 value is calculated.

Note. Instruments without graphite furnace atomization or Zeeman background correction functions are not eligible for this experiment.

5.12 Slit shifting positioning error Install and turn on a copper hollow cathode lamp, set the spectral bandwidth to

0.2 mm, and perform three unidirectional measurements on the 324.75 nm spectral line of copper. Average value. Change the spectral bandwidth, and measure three times for each other spectral bandwidth setting in the same way, and take the average value. Calculate the wavelength error of the spectral bandwidth of each gear according to formula (11), and take the one with the largest absolute value as the slit shifting positioning error of the instrument.

5.13 Stability Perform the first test according to 5.5, keep the instrument running for the specified time, and then perform the test again according to 5.5.

5.14 Instrument Appearance Visual and tactile inspection.

5.15 Instrument completeness Visual inspection.

5.16 Environmental adaptability

5.16.1 Power supply environment adaptability The test shall be conducted in accordance with the power supply voltage and frequency test specified in Chapter 3 of GB/T 11606-2007, and the test shall be performed according to 5.5.

5.16.2 Climate and Environmental Adaptability

5.16.2.1 Low Temperature Test The test shall be conducted according to the test conditions and procedures specified in

4.4 of GB/T 11606-2007, and the specified temperature conditions shall be selected. The temperature was set at 15°C for 4 hours, and the test was performed according to standard 5.5.

5.16.2.2 High Temperature Test The test shall be conducted according to the test conditions and procedures specified in sections

5.4 of GB/T 11606-2007, and the specified temperature conditions shall be selected. The temperature was set at 35°C for 4 hours, and the test was performed according to standard 5.5.

5.17 Electromagnetic Compatibility

5.17.1 Electrostatic Discharge Immunity The test shall be conducted in accordance with the contact discharge test procedure specified in GB/T 17626.2.

5.17.2 Immunity to Radio Frequency Electromagnetic Field Radiation The test shall be conducted in accordance with the procedure specified in GB/T 17626.3.

5.17.3 Electrical Fast Transient/Bulk Immunity The test shall be conducted in accordance with the procedure specified in GB/T 17626.4.

5.17.4 Surge (Impact) Immunity The test shall be conducted in accordance with the procedure specified in GB/T 17626.5.

5.18 Transportation and Storage During Transportation When the instrument is in its packaged state, the tests shall be conducted in accordance with the relevant provisions in Chapters 8 and 15 to 18 of GB/T 11606-2007.

6.3 Type Testing

6.3.1 Type testing shall be performed in accordance with the requirements of

4.18 in any of the following circumstances.

a) When the instrument design or production is finalized;

b) When the instrument is transferred to another factory or production site;

c) If, after the instrument has been put into formal production, there are significant changes in its structure, materials, or manufacturing process that may affect its performance;

d) During normal production, the instrument should be inspected periodically or after a certain production volume has been accumulated, generally not exceeding 3 years;

e) When the instrument has been out of production for a long time and production resumes;

f) When the test results differ significantly from the previous type test.

6.3.2 Samples for type testing shall be randomly selected from batches that have passed factory inspection.

6.3.3 Type testing shall be conducted in accordance with GB/T 2829, using a single sampling plan. The testing items, non-conformity classifications, and non-conformity details for the instrument shall be specified. The rated quality level (RQL) and discrimination level (DL) shall be as specified in Table

8.Batch quality shall be expressed as the number of defective instruments per 100 units.

6.3.4 If the type test fails, the cause should be analyzed, the problem identified, and corrective measures implemented. The type test should then be repeated. If the type test fails again... If the product passes the inspection, production should be suspended for rectification, and the product should be taken out of service until the problem is resolved and the type test is passed. Only then can the product be allowed to resume factory inspection.

6.3.5 If the type test is passed and the batch passes the factory inspection, it can be shipped or stored as qualified products. If it has been stored for more than 12 months, it may not be shipped. If the factory fails to inspect the product, a new factory inspection should be conducted.

6.3.6 The instrument classification is detailed in Appendix A.

7.1 Marking

7.1.1 Instrument Markings The instrument should have a nameplate affixed to a suitable and conspicuous location, and it should include the following information.

a) Manufacturer's name;

b) Instrument model;

c) Instrument name;

e) Manufacturing date and serial number;

f) Other important indicators, such as rated operating voltage and frequency.

7.1.2 Packaging Markings All markings on the instrument packaging should be clear and intuitive, and should include the following.

a) Instrument model and name;

b) Manufacturer's name and address;

c) Mass. Unit is kilogram (kg);

d) External dimensions. length × width × height, in millimeters (mm);

e) Packaging and storage symbols. "Fragile," "Upwards," "Keep away from rain," etc., should comply with GB/T 191.

f) Other important signs, such as transport signs and warning signs.

7.2 Packaging

7.2.1 Instrument Packaging Instrument packaging should comply with the moisture-proof and shock-proof packaging requirements in GB/T 13384.

7.2.2 Random Files The instrument's accompanying documentation should include.

a) Packing list;

b) Instruction manual (the safety descriptions in the instrument documentation should comply with the relevant provisions of Chapter 5 of GB 4793.1-2007);

c) Certificate of Conformity;

d) Attached spare parts list.

7.3 Transportation and storage

7.3.1 During transportation and storage, the instrument should be protected from severe impacts, rain, tipping, exposure to sunlight, and radiation.

7.3.2 Instruments should be stored in their original packaging. The warehouse environment temperature should be between 0°C and 40°C, and the relative humidity should not exceed 85%. No other items should be stored in the warehouse. Harmful substances that can cause corrosion and reduced electrical insulation of instruments.

7.3.3 The storage period for instruments should not exceed one year. After the storage period, instruments should be randomly inspected according to the factory inspection requirements.