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HJ 751-2015 English PDF

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HJ 751-2015: Solid Waste. Determination of Nickel and Copper. Flame Atomic Absorption Spectrometry
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HJ 751-2015English349 Add to Cart 3 days [Need to translate] Solid Waste. Determination of Nickel and Copper. Flame Atomic Absorption Spectrometry Valid HJ 751-2015

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Standard similar to HJ 751-2015

HJ 759   HJ 662   HJ/T 298   HJ 753   HJ 754   HJ 752   

Basic data

Standard ID HJ 751-2015 (HJ751-2015)
Description (Translated English) Solid Waste. Determination of Nickel and Copper. Flame Atomic Absorption Spectrometry
Sector / Industry Environmental Protection Industry Standard
Classification of Chinese Standard Z13
Word Count Estimation 14,182
Date of Issue 2015-08-21
Date of Implementation 2015-10-01
Quoted Standard HJ/T 20; HJ/T 298; HJ/T 299; HJ/T 300; HJ 557
Regulation (derived from) Ministry of Environment Announcement 2015 No.54
Issuing agency(ies) Ministry of Ecology and Environment
Summary This standard specifies the determination of solid waste and solid waste leachate flame atomic nickel and copper content absorption spectrophotometry. This standard applies to the determination of solid waste and solid waste leaching solution of nickel and copper.

HJ 751-2015: Solid Waste. Determination of Nickel and Copper. Flame Atomic Absorption Spectrometry


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Solid Waste.Determination of Nickel and Copper.Flame Atomic Absorption Spectrometry National Environmental Protection Standard of the People 's Republic of China Determination of nickel and copper in solid wastes Flame Atomic Absorption Spectrophotometry Solid Waste-Determination of Nickel and Copper- Flame Atomic Absorption Spectrometry 2015-08-21 release 2015-10-01 implementation Ministry of Environmental Protection Directory Preface .ii 1 Scope of application 1 2 normative reference document 1 Principle of Method 1

4 interference and elimination

5 reagents and materials

6 instruments and equipment

7 samples

8 Analysis Step 3 Results and Expressions 10 precision and accuracy

Foreword

In order to implement the Environmental Protection Law of the People's Republic of China and the Law of the People's Republic of China on the Prevention and Control of Environmental Pollution by Solid Wastes, Protect the environment, protect human health, regulate the monitoring of nickel and copper in solid waste, and develop this standard. This standard specifies the flame atomic absorption spectrophotometric method for nickel and copper in solid waste and solid waste leachate. This standard is the first release. Appendix A, Appendix B and Appendix C of this standard are informative. This standard is organized by the Ministry of Environmental Protection Science and Technology Standards Division. The main drafting unit of this standard. Nanjing Environmental Monitoring Center Station. The standard verification unit. Taizhou City Environmental Monitoring Center Station, Changzhou City Environmental Monitoring Center, Suzhou City Environmental Monitoring Center Station, Zhenjiang City Environmental Monitoring Center Station, Jiangsu Province, physical and chemical testing center, Nanjing Water Corporation Water Quality Monitoring Center. The Environmental Protection Department of this standard approves on August 21,.2015. This standard is implemented on October 1,.2015. This standard is explained by the Ministry of Environmental Protection. Solid waste - Determination of nickel and copper - Flame atomic absorption spectrophotometric method In the meantime, there is a problem in the world, and in the past. Ž '"-" - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - • ¢ £ ¤ ¥ in |

1 Scope of application

This standard specifies the flame atomic absorption spectrophotometric method for the determination of nickel and copper in solid waste and solid waste leachate. This standard applies to the determination of nickel and copper in solid waste and solid waste leachate. The detection limits of nickel and copper in solid waste leachate were 0.03 mg/L and 0.02 mg/L, respectively, and the lower limit of determination was 0.12 Mg/L and 0.08 mg/L; when the sample mass is 0.5 g and the volume of the volume is 50.0 ml after digestion, the total amount of nickel and copper in the solid waste The detection limits were 3 mg/kg and 3 mg/kg, respectively, with a lower limit of 12 mg/kg and 12 mg/kg, respectively.

2 normative reference documents

The contents of this standard refer to the following documents or their terms. For undated references, the valid version applies to this standard. Technical specification for SJ sample preparation for industrial solid waste Technical Specification for Hazardous Waste Identification HJ/T 299 Solid waste leaching toxicity leaching method sulfuric acid nitric acid method HJ/T 300 solid waste leaching toxicity leaching method acetic acid buffer solution method HJ 557 Solid waste leaching toxicity leaching method Horizontal oscillation method

3 Principle of the method

Solid waste leachate or solid waste after acid digestion, the sample of nickel and copper in the air - acetylene flame in the atomic, the ground state atoms Respectively, the selective diffraction of the characteristic radiation spectrum of nickel and copper, the absorption intensity of a certain range with the concentration of nickel and copper concentration ratio.

4 interference and elimination

Cu, Zn, Pb, Cd, Mn, Ba, Sr, B, V, As, Al, Ti, K, Na, Mg, Ca and Less than 50 mg/L of Li, Sn and other coexisting elements on the determination of nickel without interference; less than 10000 mg/L of Fe, Cr, Co and other coexistence Ni, Zn, Pb, Cd, Fe, Mn, Ba, Sr, B, V, As, Al, Ti, and Ni, which are less than 100 mg/L, Co, K, Na, Mg, Ca and less than 50 mg/L of Li, Sn and other coexisting elements on the determination of copper without interference. 4 ¨2 using 232.0 nm for the determination of nickel absorption line, there are similar wavelength of nickel three-line spectral interference, select the 0.2 nm spectral pass With the belt to avoid. 4 ¨ 3 When the sample matrix interference is serious, can be measured by standard addition method, see Appendix B.

5 reagents and materials

Unless otherwise stated, analytical analytical reagents conforming to national standards are used in the analysis, and the test water is freshly prepared deionized water. 5 ¨ 1 hydrochloric acid. ρ (HCl) = 1.19 g/ml, excellent grade pure. 5 ¨ 2 nitric acid. ρ (HNO3) = 1.42 g/ml, excellent grade pure. 5 ¨ 3 hydrofluoric acid. ρ (HF) = 1.49 g/ml, excellent grade pure. 5 ¨ 4 perchloric acid. ρ (HClO4) = 1.68 g/ml, excellent grade pure. 25 ¨ 5 Hydrogen peroxide solution. φ (H2O2) ≈ 30%. 5¨7 metal nickel (pure spectrum). 5¨8 metal copper (pure spectrum). 5 ¨ 9 Nitric acid solution. 1 1 (v/v) Measure 50ml nitric acid (5.2) and dilute to 100ml with water. 5 ¨ 10 Nitric acid solution. 1 99 (v/v) Measure 10ml nitric acid (5.2) and dilute to 1000ml with water. 5 ¨ 11 nickel standard stock solution. ρ (Ni) = 1000 mg/L Use a commercially available standard solution (nickel single element or nickel-containing multi-element mixed standard solution); or accurately weigh 1.000 g of metallic nickel (5.7) Dissolved in 10 ml nitric acid (5.2), transferred into the 1000 mL volumetric flask, the volume of water to the standard line, shake. Store in a polyethylene bottle In the cold, can be used for two years. 5 ¨ 12 copper standard stock solution. ρ (Cu) = 1000 mg/L Use commercially available standard solutions (copper single element or copper-containing multi-element mixed standard solution); or accurately weigh 1.000 g of metallic copper (5.8) Dissolved in 10 ml nitric acid (5.2), transferred into 1000 mL volumetric flask, water calibration line, shake. Stored in a polyethylene bottle, Refrigerated, can be used for two years. 5 ¨ nickel and copper mixed standard solution. ρ = 100 mg/L, Accurately measure 10.00 ml of nickel standard stock solution (5.11) and 10.00 ml of copper standard stock solution (5.12) at 100 ml capacity Bottle, with nitric acid solution (5.10) constant volume to the mark, shake. 5¨14 Acetylene. purity ≥99.5%.

6 instruments and equipment

6 ¨ Flame Atomic Absorption Spectrophotometer. 6 ¨ 2 air compressor, should be equipped with water, degreasing and dust removal device. 6 ¨ 3 microwave digestion device (power 600W ~ 1500W). 6¨4 hot plate. with temperature control function (temperature stability ± 5 ℃). 615 General laboratory equipment and equipment commonly used.

7 samples

7 ¨ 1 © ª with e « The collection and storage of solid waste samples are carried out in accordance with HJ/T 20 and HJ/T 298. 7 ¨ 2 sample h prepared 7 ¨2 ¨ solid waste ¬ out ž The solid waste leachate was prepared by HJ/T 299, HJ/T 300 or HJ 557. Leaching solution if not timely analysis, Should be added nitric acid (5.2) acidified to pH < 2, can be stored for 14d. 7¨2¨2 solid waste The solid waste sample preparation was carried out in accordance with the relevant provisions of HJ/T 20. For solid waste or dry semi-solid waste samples, said Take 10g (m1, accurate to 0.01g) samples, naturally air-dried or freeze-dried, weighing again (m2, accurate to 0.01g), grinding, all over 100 Mesh sieve spare. 7 ¨ 3 sample of the equipment 37 ¨ ¨ ¨ solid waste ¬ out of the sample 7¨3¨1¨1 electricity Measure 50.0 ml leaching solution in 150 ml beaker, add 3 ml ~ 5 ml nitric acid (5.2), shake. Cover the surface dish and place it in electricity Hot plate (6.4) in the near boiling state of the sample heated to near dry, remove the cooling; then add 3 ml of nitric acid (5.2), continue to heat, Until the digestion is complete (the digestion solution is clear or the appearance of the digestion solution no longer changes), continue to evaporate to near dry. After cooling, add 1 ml Nitric acid solution (5.9), heating and dissolving the residue, washing the inner wall of the beaker with a small amount of water and the surface dish, all transferred to 50 ml volumetric flask, Water dilution, constant volume, mix spare. Take the supernatant. 7¨3¨1¨2 yz method See Appendix C. 7 ¨3¨2 solid waste sample 7¨3¨2¨1 electricity For solid samples or dry semi-solid samples, weigh 0.1 g to 0.5 g (m3, accurate to 0.1 mg) sieved samples (7.2.2); For samples of liquid or non-dry semi-solid samples, 0.5 g (m3, accurate to 0.1 mg) was weighed directly. Place the sample in 50 ml of polyt Fluorine vinyl crucible, water wetting by adding l0 ml hydrochloric acid (5.1), placed in the electric plate (6.4) on the heated (about 50 ℃), the initial digestion, To be evaporated to about 3 ml, add 5 ml of nitric acid (5.2) and 5 ml of hydrofluoric acid (5.3), after capping at 120 ℃ ~ 130 ℃ heating 0.5 h ~ 1 h. Cooling, add 2 ml of perchloric acid (5.4), and then cover, at 150 ℃ ~ 160 ℃ heating about 1 h, open the lid, drive White smoke and steamed into the contents of the liquid is not the state of the liquid beads (hot observation). Depending on the situation, can be added 3 ml nitric acid (5.2), 3 ml Hydrofluoric acid (5.3) and 1 ml perchloric acid (5.4), repeat the above digestion process. Remove the crucible slightly cold, rinse the crucible lid and the inner wall with water, Add 1 ml of nitric acid solution (5.9), dissolve the soluble residue in warm, transferred to 50 ml volumetric flask, after cooling with water volume to the mark, Shake well Note 1. If the content of nickel or copper in solid waste is high, the volume of volume determined after digestion can be determined according to the actual situation. Note 2. If the content of nickel or copper in solid waste is low, it can be determined by graphite furnace atomic absorption spectrophotometry. 7 ¨3¨2¨2 yz method See Appendix C.

8 Analysis steps

8 ¨ instrument measurement ¯ ° ± pieces Refer to the conditions listed in Table 1 to adjust the instrument so that the flame state, burner height and so on to achieve the best. Table 1 instrument ¯ ° measurement ± pieces Element Ni Cu Light source nickel hollow cathode lamp copper hollow cathode lamp Lamp current (mA) 3.0 3.0 Measurement wavelength (nm) 232.0 324.7 Sub - sensitive line (nm) 352.5 327.8 Passband width (nm) 0.2 0.5 Lamp current (mA) 3.0 3.0 Flame properties Flammishing and burning Flame

4 Combustion height allows the hollow cathode light spot to pass through the bright blue part

Button background way deuterium lamp background correction 8 ¨ 2 ² quasi (5.13) 0.00 ml, 0.20 ml, 0.50 ml, 1.00 ml, 2.00 ml, 3.00 ml, 5.00 ml In 100 ml volumetric flask, with nitric acid solution (5.10) constant volume and shake. This standard series contains nickel and copper, respectively 0.00 mg/L, 0.20 Mg/L, 0.50 mg/L, 1.00 mg/L, 2.00 mg/L, 3.00 mg/L and 5.00 mg/L. According to the instrument measurement conditions (8.1), with nitric acid solution (5.10) to adjust the instrument zero, according to the low concentration to high concentration of the order of suction Into the standard series, measure the corresponding absorbance, the corresponding absorbance as the ordinate, the standard series of the standard mass concentration for the abscissa, Draw the calibration curve for each element. 8 ¨3 ³'try The reagent blank sample was prepared according to the procedure of 7.3 and measured at 8.4. 8 ¨4 determination The prepared samples were measured with the same instrumental analysis conditions as the calibration curve.

9 Results calculation and representation

9 ¨ solid waste ¬ out of the test results calculated The mass concentration ρ (mg/L) of nickel or copper in the solid waste leachate is calculated according to the formula (1) 01) (V V   (1) Where.  - mass concentration of solid waste leachate, mg/L; 1  - Check the calibration curve to determine the concentration of the element in the sample, mg/L; 0_1 - Mass concentration in the laboratory blank sample, mg/L; 0V - the volume of the sample after digestion of the leachate, ml; 1V - Sampling volume of solid waste leachate, ml. 9 ¨ solid waste test results calculated 9 ¨ 2 ¨ 1 solid μ and ¶ dry ‡ · solid μ solid waste The content of nickel or copper in solid waste (mg/kg) is calculated according to formula (2) 001) ( V    (2) Where.  - the content of the element in the solid waste, mg/kg; 1 ü - the mass concentration of the element in the assay sample as determined by the calibration curve, mg/L; 0_1 - Mass concentration in the laboratory blank sample, mg/L; 0V - volume of the sample after digestion, ml; M1 - the amount of solid waste sample weighed, g; M2 - the mass of the solid waste sample after drying, g; M3 - the amount of sample to be sieved, g. 59 ¨2 ¨2 žμ and ¸ ¶ dry solid solid waste Solid content of nickel or copper in the waste ω (mg/kg) calculated according to formula (3). 001) ( V   (3) Where.  - Element content in solid waste, mg/kg; 1_1 - mass concentration of the element in the sample from the calibration curve, mg/L; 0_1 - mass concentration of the element in the laboratory blank sample, mg/L 0V - volume of the sample after digestion, ml; M3 - the amount of solid waste sample weighed, g; 9 ¨ 3 results that When the determination result of the solid waste leaching solution is less than 1 mg/L, two digits after the decimal point are retained; when the determination result is greater than or equal to 1 mg/L , Keep 3 significant digits. 9 ¨3¨2 When the total amount of solid waste determination results less than 100 mg/kg, the retention of three significant figures, when the determination is greater than or equal to 100 Mg/kg, retained to the integer position. 10 precision and accuracy 10¨1 precision Six laboratories used electric plate method to digest the actual solid waste leachate samples containing nickel and copper were tested, and the laboratory phase The standard deviation range is. 0.7% ~ 8.6%, 1.6% ~ 4.4%; the relative standard deviation range of laboratory is. 2.3% ~ 8.6% 2.6% ~ 3.4%; repeatability were. 0.01mg/L ~ 0.02mg/L, 0.03mg/L ~ 0.04mg/L; reproducibility limit were. 0.02 mg/L to 0.05 mg/L, 0.04 mg/L to 0.06 mg/L. Six laboratories used the hot plate method to test the actual solid waste samples containing nickel and copper and the standard samples. The laboratory phase The standard deviation range is 2.2% ~ 8.5%, 2.6% ~ 9.8%; the relative standard deviation range of the laboratory is 2.6% ~ 7.9% 2.8% ~ 8.4%; repeatability limit. 7.10mg/kg ~ 79.4mg/kg, 2.91mg/kg ~ 87.9mg/kg; reproducibility limit were. 11.0 mg/kg to 93.1 mg/kg, 4.02 mg/kg to 99.8 mg/kg. Details of precision data are shown in Schedule A.1 and Schedule A.2. 10¨2 accuracy Six laboratories using hot plate method of nickel, copper, the actual solid waste leachate spiked samples were tested, spiked recovery rate The range is 87.1% ~ 112%, 87.3% ~ 109%. Six laboratories used a hot plate method to test the solid waste uniform standard samples, the relative error were. -4.6% ~ 2.4% -14.2% to 7.1%. The accuracy data are detailed in Schedule A.3 and Schedule A.4. 11 quality ef and mass gh 11¨1 each batch of samples to do at least two laboratory reagents blank, the blank target element of the determination of the results should be lower than the detection limit. 11 ¨ 2 Each analysis should be drawn calibration curve, with the least squares method for linear fitting, the correlation coefficient should be ≧ 0.999, otherwise need to re- Draw a calibration curve. Each batch of samples (up to 20 samples) after the analysis, the need to determine the calibration series of zero concentration and intermediate concentration points for calibration verification. 6 zero concentration point determination should be lower than the method detection limit, the intermediate concentration measured value and the point of the relative deviation of ≤ 10%, otherwise it should be re-painted Calibration curve. 11 ¨ 3 samples per batch (up to 20 samples) should be tested at least once in parallel (less than 20 samples at least once), parallel The relative deviation of the two-phase measurement should be ≤15%. 11 # 4 samples per batch (up to 20 samples) should be tested at least one random sample at random (less than 20 samples Once), spike recovery rate should be between 80% to 120%. If required, a certified standard quality control sample can be measured at the same time Guaranteed value range. 12 waste i material of the rationale The waste and waste generated in the experiment shall be collected and sent to the competent units for centralized treatment. 13 klmn 13 ¨ 1 experiments used glassware must first wash with detergent, and then (1 1) nitric acid solution soak 24h, and then followed by tap water, Deionized water washed, controlled dry, spare. 13¨2 used glassware and nitric acid and other reagents before use to be blank check to meet the blank requirements to use. 13 ¨ 3 hot plate temperature should not be too high to prevent the deformation of PTFE crucible; sample digestion, in the steam to near dry need to be particularly careful, To prevent dry, otherwise the element will be measured loss. 13 ¨ 4 solid waste types are complex, the matrix difference is large, in the digestion of the amount of acid, digestion temperature and retention time visual digestion Increase or decrease as appropriate. 7op A (S) op Method of precision and accuracy Table q ¨ solid waste ¬ out of the method of precision element name concentration (Mg/L) Laboratory relative standard deviation(%) Inter-laboratory relative standard deviation(%) Repeatability limit R (mg/L) Reproducibility limit R ((mg/L)) Ni 0.07 4.2 to 8.6 8.6 0.01 0.02 0.65 0.74 to 2.1 2.3 0.03 0.05 01.048 Cu 0.33 2.6 to 4.4 3.4 0.03 0.04 0.62 1.6 to 2.4 2.6 0.04 0.06 O Table q ¨ Solid Waste Method Precision element name

content

(Mg/kg) Laboratory relative standard deviation(%) Inter-laboratory relative standard deviation(%) Repeatability limit R (mg/kg) Reproducibility limit R (mg/kg) Ni 40.3 4.2 ~ 8.5 7.9 7.10 11.0 816 2.2 ~ 4.4 2.6 79.4 93.1 Cu 782 5.5 to 9.8 2.7 87.9 99.8 12.9 2.6 to 5.4 8.4 2.91 4.02 O Table q ¨ solid waste ¬ out of the method of accuracy element name Concentration (mg/L) plus scalar (mg/L) Spiked recovery rate (%) The final value of the recoveries (%) Ni 0.07 0.20 90.3 to 112 99.6 16.0 0.65 0.50 87.1 to 103 94.0 ± 10.8 Cu 0.33 0.20 89.1 to 109 97.4 ± 14.2 0.62 0.50 87.3 to 102 92.9 ± 10.4 O Table q ¨ Solid waste method accuracy Element name Content (mg/kg) Standard assurance (mg/kg) Relative error final value (%) Ni 816 833 ± 40.0 -2.0 ± 5.0 Cu 12.9 13.8 ± 2.2 -6.8 ± 15.6 8op B (S) op Standard vw method U ¨ 1 ² quasi ¹º »h Were measured 4 equal parts to be tested samples (concentration of Cx), the preparation of the same volume of the same 4 copies of the solution. The first without standard solution, The concentrations of the four solutions were as follows. Cx, Cx Co, Cx 2Co, Cx 3Co, add the standard minimum concentration Co ≈ 0.5Cx. The blank solution was zeroed and the suction of the solution was measured in the same order Luminosity value. With the absorbance value as the ordinate, add the standard solution concentration for the abscissa, draw the calibration curve, the curve of the reverse extension and horizontal The intersection of the coordinates is the concentration of the sample to be measured. This method is only applicable to areas where the concentration and absorbance are linear. The concentration of the test sample to be tested The relationship between the absorbance values is shown in Figure A.1. O ¼ u ¨ 1 ½ test ¾ degree and ¿. • Absorbance À  U ¨2 klmn B.2.1 The volume error caused by the addition of the standard solution should not exceed 0.5%. B.2.2 The use of standard addition method can only eliminate the impact of matrix effects, can not eliminate the impact of background absorption. The applicability of the standard vw method Determine the absorbance of the sample to be tested as A, from the calibration curve to find the concentration of x. And then add the standard solution to the test sample standard concentration The degree of s, measured its absorbance B, from the calibration curve to find the concentration of y. Use the following formula to calculate the actual sample content c. Xy Sc ) When there is a matrix effect, Xy  between 0.5 and 1.5, available standard addition method, when xy  When this range is exceeded, the standard is added Law does not apply. 9op C (S) op Yz X ¨ 1 ¬ out of the sample Take 50.0 ml of the leachate sample (the volume of the digested leachate and the added acid should be less than the limit of the microwave digestion Product) in the microwave digestion tank, if the sample of organic matter content is low, add 5 ml of nitric acid (5.2); if the sample of organic matter content is high, Add 5 ml of nitric acid (5.2), 1 ml of hydrochloric acid (5.1) and 1 ml of hydrogen peroxide solution (5.5) for 30 min, Into the microwave digestion device, according to the set temperature program (Table C.1) to digest. Digestion is completed, to be the tank temperature and room temperature balance, The digestion tank was placed on a hot plate and the sample was heated to near dryness and cooled in a near boiling state. Add 1 ml of nitric acid solution (5.12) Heating dissolved residue, with a small amount of water to clean the digestion tank wall and cover, all transferred to 50 ml volumetric flask, diluted with water, constant volume, Mix well. Take the supernatant. O table x ¨ 1 yz x {ÄÅÆÇ¡ È Heating time (min) Digestion temperature (℃) Holding time (min) 10 rose from room temperature to 180 15 X ¨ solid waste sample For solid samples or dry semi-solid samples, weigh 0.1 g to 0.5 g (m3, accurate to 0.1 mg) sieved samples (7.2.2); For liquid or non-dry semi-solid samples directly weighed the sample 0.5g (m3, accurate to 0.1mg) (oil-containing waste should be appropriate to take less). The samples were placed in a microwave digestion tank and wetted with a small amount of water followed by the addition of 6 ml of nitric acid (5.2), 2 ml of hydrochloric acid (5.1), 2 ml to 5 ml Hydrofluoric acid (5.3) was digested according to the programmed temperature programmed (Schedule C.2), after cooling (or transferring the solution to 50 ml of polytetrafluoro Ethylene crucible) by adding 1 ml of perchloric acid (5.4), the heating plate heated silicon, the temperature control in the 150 ℃ -160 ℃, heated to the concentration Thick aluminic acid white smoke and the contents were not flow state, remove the crucible slightly cold, with a small amount of water rinse the crucible lid and the inner wall, add 1 ml of nitrate Acid solution (5.12), dissolve the soluble residue in warm, transferred to 50 ml volumetric flask, cooled and then fixed to the mark with water, shake. O table x ¨2 yz x {ÄÅÆÇ¡ È Heating time (min) Digestion temperature (℃) Holding time (min) 7 rose from room temperature to 120 3 5 120 ~ 160 3 5 160 ~ 190 25 X¨3 klmn X ¨3¨1. solid waste more types, the matrix difference is large, in the digestion of solid waste when the amount of acid, digestion temperature and retention time Visible digestion as appropriate. X ¨3¨2 ~ microwave digestion process due to excessive pressure caused by instrument pressure, sealing system is damaged, this batch of samples will not be used.

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