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HJ 1150-2020
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Basic data | Standard ID | HJ 1150-2020 (HJ1150-2020) | | Description (Translated English) | (Water quality Determination of nitrophenol compounds Gas chromatography-mass spectrometry) | | Sector / Industry | Environmental Protection Industry Standard | | Classification of Chinese Standard | Z16 | | Word Count Estimation | 28,270 | | Date of Issue | 2020-12-09 | | Date of Implementation | 2021-03-01 | | Regulation (derived from) | Ministry of Ecology and Environment Announcement No. 61 (2020) | | Issuing agency(ies) | Ministry of Ecology and Environment |
HJ 1150-2020: (Water quality Determination of nitrophenol compounds Gas chromatography-mass spectrometry) ---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.
(Water quality Determination of nitrophenol compounds Gas chromatography-mass spectrometry)
National Environmental Protection Standards of the People's Republic of China
Water quality determination of nitrophenol compounds
Gas chromatography-mass spectrometry
Water quality-Determination of nitrophenols
-Gas chromatography mass spectrometry
2020-12-09 release
2021-03-01 implementation
Issued by the Ministry of Ecology and Environment
i table of contents
Foreword...ii
1 Scope of application...1
2 Normative references...1
3 Principles of the method...1
4 Reagents and materials...1
5 Instruments and equipment...3
6 Sample...3
7 Analysis steps...5
8 Calculation and presentation of results...8
9 Precision and accuracy...9
10 Quality Assurance and Quality Control...10
11 Disposal...11
Appendix A (Normative Appendix) Method detection limit and lower limit of determination...12
Appendix B (informative appendix) Summary of method precision data...13
Appendix C (informative appendix) Summary of method accuracy data...22
Foreword
To implement the Environmental Protection Law of the People’s Republic of China and the Water Pollution Prevention Law of the People’s Republic of China, and protect the ecology
The environment, to protect human health, regulate the determination method of nitrophenol compounds in water, and formulate this standard.
This standard specifies the determination of 12 nitrophenol compounds in surface water, groundwater, domestic sewage, industrial wastewater and seawater
Gas chromatography-mass spectrometry.
Appendix A of this standard is a normative appendix, and Appendix B and Appendix C are informative appendices.
This standard is issued for the first time.
This standard was formulated by the Department of Ecological Environment Monitoring and the Department of Regulations and Standards of the Ministry of Ecology and Environment.
Drafting organization of this standard. Jiangsu Environmental Monitoring Center.
Verifiers of this standard. Zhenjiang Environmental Monitoring Center of Jiangsu Province, Changzhou Environmental Monitoring Center of Jiangsu Province, Taizhou Environmental Monitoring Center of Jiangsu Province
Environmental Monitoring Center, Nantong Environmental Monitoring Center of Jiangsu Province, and Huaian Environmental Monitoring Center of Jiangsu Province.
This standard was approved by the Ministry of Ecology and Environment on December 9, 2020.
This standard will be implemented on March 1, 2021.
This standard is interpreted by the Ministry of Ecology and Environment.
1 Water quality Determination of nitrophenolic compounds Gas chromatography-mass spectrometry
Warning. The standard substances and organic solvents used in the experiment are toxic and hazardous substances. The reagent preparation and sample pretreatment process
It should be carried out in a fume hood; protective equipment should be worn as required during operation to avoid contact with skin and clothing.
1 Scope of application
This standard specifies the gas chromatography-mass spectrometry method for the determination of nitrophenol compounds in water.
This standard applies to 2-nitrophenol and 3-methyl-2-nitro groups in surface water, groundwater, domestic sewage, industrial wastewater and seawater.
Phenol, 4-methyl-2-nitrophenol, 5-methyl-2-nitrophenol, 2,5-dinitrophenol, 3-nitrophenol, 2,4-dinitrophenol, 4- Nitrophenol,
12 kinds of 2,6-dinitrophenol, 3-methyl-4-nitrophenol, 6-methyl-2,4-dinitrophenol and 2,6-dimethyl-4-nitrophenol Nitrophenol
Determination of compounds.
When the sampling volume is 1000 ml and the sample volume is 1.0 ml, the detection limit of the method for 12 nitrophenol compounds
It is 0.2 μg/L~2 μg/L, and the lower limit of determination is 0.8 μg/L~8 μg/L. See Appendix A for details.
2 Normative references
This standard quotes the following documents or their clauses. For undated reference documents, their valid versions are applicable to this
standard.
GB 17378.3 Marine Monitoring Specification Part 3.Sample Collection, Storage and Transportation
GB/T 14581 Technical Guidelines for Water Quality Sampling in Lakes and Reservoirs
HJ/T 91 Technical specification for surface water and sewage monitoring
HJ 91.1 Technical Specification for Wastewater Monitoring
HJ/T 164 Technical Specification for Groundwater Environmental Monitoring
3 Principles of the method
After the sample is purified by acid-base distribution, under acidic conditions (pH value of 1~2), use liquid-liquid extraction or solid phase extraction
The nitrophenol compound is extracted by extraction method, and the extract is dehydrated, concentrated, and fixed to volume, and then separated by gas chromatography and detected by mass spectrometry. according to
Retention time, fragment ion mass-to-charge ratio and abundance ratio are qualitative, and internal standard method is used for quantification.
4 Reagents and materials
Unless otherwise specified, analytical reagents that meet national standards are used for analysis, and the experimental water does not contain target compounds
Distilled water or water prepared by pure water equipment.
4.1 Dichloromethane (CH2Cl2). pesticide residue level.
4.2 Acetone (CH3COCH3). pesticide residue level.
4.3 Methanol (CH3OH). pesticide residue level.
4.4 Hydrochloric acid. ρ(HCl)=1.18 g/ml.
24.5 Sodium hydroxide (NaOH).
4.6 Anhydrous sodium sulfate (Na2SO4).
Bake in a muffle furnace at 400°C for 4 hours, cool to room temperature in a desiccator, and put it in a reagent bottle for sealed storage.
4.7 Sodium chloride (NaCl).
Bake in a muffle furnace at 400°C for 4 hours, cool to room temperature in a desiccator, and put it in a reagent bottle for sealed storage.
4.8 Hydrochloric acid solution. 1 1.
4.9 Hydrochloric acid solution. c(HCl)=0.02 mol/L.
Measure 1.8 ml of hydrochloric acid (4.4), slowly add it to water, transfer to a 1000 ml volumetric flask, dilute to the mark.
Available for immediate use.
4.10 Sodium hydroxide solution. c(NaOH)=5.0 mol/L.
Weigh 20.0 g of sodium hydroxide (4.5), dissolve it with water, transfer to a 100 ml volumetric flask, dilute to the mark. Near
Use now.
4.11 Standard material. purity ≥99%.
2-nitrophenol, 3-methyl-2-nitrophenol, 4-methyl-2-nitrophenol, 5-methyl-2-nitrophenol, 2,5-dinitrophenol, 3- Nitrate
Phenol, 2,4-dinitrophenol, 4-nitrophenol, 2,6-dinitrophenol, 3-methyl-4-nitrophenol, 6-methyl-2,4-dinitrophenol Phenol and 2,6-
Dimethyl-4-nitrophenol.
4.12 Standard stock solution. ρ=1000 mg/L.
Weigh 50 mg (accurate to 0.1 mg) of nitrophenol compound standard materials (4.11), and use a small amount of methanol (4.3)
Dissolve, transfer to a 50 ml brown volumetric flask, dilute with dichloromethane (4.1) to the mark, and mix. The standard solution
Frozen and protected from light below -10℃, it can be stored for half a year. It is also possible to directly purchase commercially available certified standard solutions and keep them in accordance with the instructions.
4.13 Standard liquid. ρ=200 mg/L.
Dilute the standard stock solution (4.12) with dichloromethane (4.1). It can be stored for 2 months at 4°C in the dark and airtight.
4.14 Internal standard stock solution. ρ=2000 mg/L.
Naphthalene-d8 and acenaphthylene-d10 should be used as internal standards for nitrophenol compounds. Commercially available certified standard solutions should be kept as per the instructions.
4.15 Internal standard liquid. ρ=500 mg/L.
Dilute the internal standard stock solution (4.14) with dichloromethane (4.1).
4.16 Decafluorotriphenylphosphine (DFTPP) solution. ρ=1000 mg/L. Commercially available certified standard solution, guaranteed according to the instruction time
Save.
4.17 Decafluorotriphenylphosphine use solution. ρ=50 mg/L.
Dilute the decafluorotriphenylphosphine (DFTPP) solution (4.16) with dichloromethane (4.1).
4.18 Solid phase extraction column. 500 mg/6 ml, the packing is divinylbenzene-N-vinylpyrrolidone, or equivalent solid phase extraction column.
4.19 Solid phase extraction disc. a commercial disc with a diameter of 47 mm, with a medium layer of divinylbenzene-N-vinylpyrrolidone, or etc.
Effective solid phase extraction disk.
4.20 Filter membrane. 0.45 μm polytetrafluoroethylene membrane.
4.21 Absorbent cotton.
After soaking in dichloromethane (4.1) and acetone (4.2) in turn, dry it for later use.
4.22 Carrier gas. helium, purity ≥99.999%.
4.23 Nitrogen. purity ≥99.99%.
35 Apparatus and equipment
5.1 Gas Chromatograph-Mass Spectrometer. The gas chromatograph has a split/splitless injection port, and the column temperature can be programmed to increase temperature. Mass spectrometry has
70 eV electron impact (EI) source.
5.2 Chromatographic column. length 30 m, inner diameter 0.25 mm, film thickness 0.25 μm, stationary phase is 5%-phenyl-95% methyl polysilicon
Capillary column for oxane. Or other equivalent capillary chromatographic columns.
5.3 Solid phase extraction device. column solid phase extraction device, disc solid phase extraction device.
5.4 Concentration device. nitrogen blowing concentrator, rotary evaporator or other equipment with equivalent performance.
5.5 Sample bottle. 2 L, a brown glass bottle with a ground stopper.
5.6 Triangular funnel. 40 mm in diameter.
5.7 Anhydrous sodium sulfate drying device.
Fill a small amount of absorbent cotton (4.21) in the lower part of the triangular funnel (5.6), and fill the inside with 3 cm~5 cm thick anhydrous sodium sulfate (4.6),
Before use, rinse with 5 ml acetone (4.2) and 5 ml dichloromethane (4.1).
5.8 Micro syringe or pipette. 5 μl, 10 μl, 50 μl, 100 μl, 250 μl, 1.0 ml.
5.9 Separation funnel..2000 ml, with PTFE piston.
5.10 Analytical balance. the actual division value d = 0.1 mg.
5.11 Injection bottle. 2ml brown bottle.
5.12 Instruments and equipment commonly used in general laboratories.
6 samples
6.1 Sample collection and storage
The samples are collected in accordance with the relevant regulations of GB/T 14581, HJ 91.1, HJ/T 91, HJ/T 164 and GB 17378.3
set. When collecting samples, do not pre-wash the vials with samples (5.5). After the sample is collected, add hydrochloric acid solution (4.8) to adjust
pH≤2.The sample should be filled with the sample bottle and sealed with a cap, and kept under refrigerated and protected from light below 4℃. The sample should be divided as soon as possible after collection
If it cannot be analyzed in time, it should be extracted within 7 days. The extract should be stored in a refrigerated and darkened below 4°C. The analysis should be completed within 20 days.
Analysis.
6.2 Preparation of samples
6.2.1 Acid-base distribution and purification
Shake the sample (6.1) well, measure out 1000 ml, adjust the pH ≥ 12 with sodium hydroxide solution (4.10), and place it in the separatory leak
Add 60 ml of dichloromethane (4.1) to the bucket (5.9), shake and extract for 10 minutes, and discard the organic phase after standing to separate the layers.
Adjust the pH to 1-2 with hydrochloric acid solution (4.8) and wait for extraction.
Note 1.The sampling volume can be adjusted appropriately according to the actual sample situation.
Note 2.If the color of the organic phase is darker, the extraction times can be appropriately increased to 2 to 3 times.
46.2.2 Extraction
6.2.2.1 Liquid-liquid extraction
Add 40 g of sodium chloride (4.7) to the sample (6.2.1) after acid-base distribution and purification, and shake to completely dissolve it. Join
60 ml of dichloromethane (4.1), shake and extract for 10 min. After standing for separation, collect the organic phase and dry with anhydrous sodium sulfate
The device (5.7) is dehydrated and collected in the concentration tube. Repeat the above steps two more times to combine the organic phases.
6.2.2.2 Column solid phase extraction
Fix the solid phase extraction column (4.18) on the solid phase extraction device (5.3), use 5 ml dichloromethane (4.1), 5 ml
Methanol (4.3) and 10 ml hydrochloric acid solution (4.9) activate the solid phase extraction column and keep the column head moist. After the acid-base distribution and purification
The sample (6.2.1) is enriched by the solid phase extraction column at a rate of 3 ml/min~5 ml/min, and then vacuum suction is continued until it is small
The column is completely dry. Use 10 ml dichloromethane (4.1) to elute at a rate of 1 ml/min~2 ml/min, and use a concentrated tube to receive the wash
Deliquid.
6.2.2.3 Disk solid phase extraction
Fix the solid phase extraction disk (4.19) on the solid phase extraction device (5.3), and use 5 ml dichloromethane (4.1), 5 ml
Methanol (4.3) and 10 ml hydrochloric acid solution (4.9) activate the solid phase extraction disk and keep the disk moist. After the acid-base distribution and purification
After enriching the sample (6.2.1) through the solid phase extraction disk at a rate of 20 ml/min~30 ml/min, continue vacuum suction until
The disc is completely dry. Elute with 25 ml dichloromethane (4.1) and receive the eluent with a concentrating tube.
When using solid phase extraction, if you use an automatic solid phase extraction instrument to extract samples, follow the instrument operating procedures.
Note 1.When using the solid phase extraction method, if the sample (6.2.1) contains a higher concentration of suspended matter, the sample can be filtered with a filter membrane (4.20) first.
Then perform solid phase extraction.
Note 2.For samples with complex matrix and high organic content (6.2.1), in order to avoid penetration, two identical solid phase extraction columns can be used separately
Or plate, extract the same sample of different volumes. When the measurement result of the latter is lower than 20% of the former, it means the adsorption capacity of the latter
The amount has reached saturation, it is necessary to appropriately reduce the sampling amount or dilute the sample before solid-phase extraction.
6.2.3 Concentration
At room temperature, the extract (6.2.2) is concentrated to 0.5 ml~0.8 ml with a nitrogen blowing concentrator (5.4), and 10
μl internal standard standard use solution (4.15), dilute the volume to 1.0 ml with dichloromethane (4.1), transfer to the sample bottle (5.11),
To be tested.
6.3 Preparation of blank samples
Replace the sample with experimental water, and prepare the laboratory blank sample according to the same steps as the sample preparation (6.2)
Prepared.
92V-constant volume of sample, ml;
1V-sampling volume, ml;
D--Dilution multiple.
8.3 Presentation of results
The retention of the decimal places of the determination result is consistent with the detection limit of the method, and up to three significant digits are retained.
9 Precision and accuracy
9.1 Precision
Six laboratories uniformly blank spiked with nitrophenol compounds at concentrations of 5.0 μg/L, 15.0 μg/L, and 50.0 μg/L
The samples were subjected to 6 repeated determinations. when the liquid-liquid extraction method was used, the relative standard deviations in the laboratory were 3.1%-14%,
0.7%~12%, 0.4%~3.0%; the relative standard deviations between laboratories are 0.8%~6.3%, 0.7%~2.4%, 0.5%~
1.8%; repeatability limits are 1 μg/L~1.4 μg/L, 1 μg/L~2.8 μg/L, 1.6 μg/L~2.7 μg/L; reproducibility limits
They are 1 μg/L~1.6 μg/L, 1.1 μg/L~2.9 μg/L, 1.7 μg/L~3.1 μg/L. When using column solid phase extraction, the actual
The relative standard deviations in the laboratory are 1.7% to 15%, 0.7% to 7.6%, and 0.4% to 3.0%; the relative standard deviations between laboratories
The differences are 1.3%~5.6%, 1.0%~3.8%, 0.5%~1.8%; the repeatability limits are 1 μg/L~1.5 μg/L, 1 μg/L~
2.2 μg/L, 1.6 μg/L~2.7 μg/L; reproducibility limits are 1 μg/L~1.6 μg/L, 1 μg/L~2.3 μg/L, 1.7 μg/L~
3.1 μg/L. When using disc solid phase extraction method, the relative standard deviations in the laboratory are 0.4%-15%, 0.8%-76%,
0.4%~2.6%; the relative standard deviations between laboratories are 1.2%~7.1%, 0.7%~1.9%, 0.5%~1.3%; repeat
The reproducibility limits are 1 μg/L~1.5 μg/L, 1.5 μg/L~2.3 μg/L, 1.6 μg/L~3.0 μg/L; the reproducibility limits are 1
μg/L~1.6 μg/L, 1.5 μg/L~2.4 μg/L, 1.8 μg/L~3.2 μg/L.
Six laboratories added nitrophenol compounds with a spiked concentration of 15.0 μg/L in surface water, groundwater, and domestic sewage
Different types of actual samples were subjected to 6 repeated determinations. when using liquid-liquid extraction, the relative standard deviations in the laboratory were respectively
0.7%~16%, 2.0%~18%, 1.2%~9.1%; the relative standard deviations between laboratories are 1.6%~4.5%, 1.5%~
4.3%, 0.7%~3.0%; repeatability limits are 1.3 μg/L~3.4 μg/L, 1.1 μg/L~4.1 μg/L, 1.2 μg/L~2.3
μg/L; the reproducibility limits are 1.3 μg/L~3.6 μg/L, 1.2 μg/L~4.4 μg/L, 1.3 μg/L~2.5 μg/L, respectively. Use column
For the solid phase extraction method, the relative standard deviations in the laboratory are 2.6%-14%, 1.4%-17%, 0.7%-11%, respectively;
The relative standard deviations between rooms were 1.2%~3.6%, 1.3%~3.6%, 0.7%~2.7%, respectively; the repeatability limits were 2.2%
μg/L~3.1 μg/L, 1.9 μg/L~3.9 μg/L, 1 μg/L~2.8 μg/L; the reproducibility limits are 2.4 μg/L~3.3 μg/L,
1.9 μg/L~4.2 μg/L, 1 μg/L~3.0 μg/L. When using disk solid phase extraction, the relative standard deviations in the laboratory are respectively
1.1%~15%, 2.8%~15%, 1.5%~7.9%; the relative standard deviations between laboratories are 1.1%~4.1%, 1.1%~
3.5%, 0.7%~2.1%; repeatability limits are 1 μg/L~3.5 μg/L, 2.3 μg/L~3.5μg/L, 1.4 μg/L~2.3 μg/L;
The reproducibility limits were 1 μg/L~3.6 μg/L, 2.4 μg/L~3.5 μg/L, 1.4 μg/L~2.5 μg/L, respectively.
In the laboratory, the seawater and industrial wastewater samples with a spiked concentration of 15.0 μg/L were repeatedly tested for 6 times.
In the liquid extraction method, the relative standard deviations in the laboratory were 8.1%~15.4%, 6.4%~14.6%; column solid phase extraction method was used
The relative standard deviations in the laboratory were 7.9%~17.3% and 7.9%~16.5% respectively; when the disc solid phase extraction method was used, the actual
The relative standard deviations in the laboratory were 5.0%-13.6% and 3.7%-15.1%.
See Appendix B for summary data of method precision.
9.2 Accuracy
Six laboratories have uniformly blank spiked concentrations of 5.0 μg/L, 15.0 μg/L, and 50.0 μg/L containing nitrophenol compounds.
The sample was repeated 6 times.
When using liquid-liquid extraction, the relative error ranges are -18.0%~6.0%, -6.0%~2.0%, -5.0%~-4.0%,
The final values of relative error are -11.3%±7.0%~-1.3%±11.8%, -4.6%±2.8%~0.6%±2.8%, -2.9%
±1.0%~-1.1%±1.2%.
When using column solid phase extraction, the relative error ranges are -20.0%~-2.0%, -6.0%~4.0%, -5.0%~0%,
The final values of relative error are -14.7%±7.0%~-7.0%±6.0%, -4.4%±2.0%~1.1%±2.0%, -3.2%
±1.0%~-0.9%±1.0%.
When using disk solid phase extraction, the relative error ranges are -18.0%~8.0%, -6.0%~2.0%, -4.2%~
0.4%, the final relative error values are -14.3%±4.6%~-5.3%±8.2%, -4.6%±3.0%~0.3%±2.4%,
-2.9%±2.0%~-0.4%±1.2%.
Six laboratories tested surface water, groundwater, and domestic sewage containing nitrophenol compounds at a concentration of 15.0 μg/L.
Different types of actual samples were tested for 6 times.
When the liquid-liquid extraction method is used, the recovery rates of standard addition are 67.3%~82.0%, 68.0%~84.0%, 67.1%~
82.8%, the final recovery rate of standard addition was 69.8%±3.8%~79.0%±3.2%, 69.8%±2.9%~81.4%±
3.1%, 68.7%±2.3%~81.2%±2.3%.
When using column solid phase extraction, the recovery rates of standard addition are 72.0%~83.3%, 68.0%~80.7%, 66.0%~
87.4%, the final recovery rate of standard addition is 75.2%±3.5%~81.1%±2.3%, 70.6%±4.3%~76.9%±
5.2%, 70.1%±2.0%~85.6%±2.8%.
When disc solid phase extraction is used, the recovery rates of standard addition are 70.7%~84.0%, 74.0%~83.3%, 74.6%~
86.1%, the final recovery rate of standard addition is 71.4%±1.6%~79.7%±3.7%, 76.1%±2.0%~81.4%±
3.3%, 76.8%±2.7%~84.4%±3.9%.
In the laboratory, the seawater and industrial wastewater samples with a spiked concentration of 15.0 μg/L were repeatedly tested for 6 times.
In the liquid extraction method, the recovery rate of standard addition is 73.3%~83.1%, 73.3%~83.7%; when the column solid phase extraction method is used, the addition
The standard recovery rate ranges from 76.9% to 84.6%, 76.9% to 84.3%; when the disc solid phase extraction method is used, the standard recovery rate range
It is 72.2%~86.3%, 72.6%~86.5%.
Refer to Appendix C for summary data of method accuracy.
10 Quality Assurance and Quality Control
10.1 Blank test
Make at least one laboratory blank for every 20 samples or every batch (≤20/batch), and the measurement result should be lower than the method detection
limit.
10.2 Calibration
The standard series requires at least 5 concentrations. The RSD of the target compound's relative response factor should be ≤20%, or the standard curve
The relationship number should be ≥0.995.
For every 20 samples or every batch (≤20/batch), a standard series of intermediate concentration points should be measured, and the measurement results are consistent with the standard
The relative error of the concentration at this point of the standard series should be within ±20%.
10.3 Parallel sample determination
At least 1 parallel sample should be measured for every 20 samples or every batch (≤20/batch), and the relative deviation of the parallel sample determination results
Should be ≤25%.
10.4 Determination of matrix spike recovery rate
Every 20 samples or every batch (≤20/batch) should measure at least 1 matrix spiked sample, the matrix spiked recovery rate should be in
Between 65% and 110%.
11 Waste treatment
The waste generated in the experiment should be collected separately, kept in a unified manner, and marked accordingly, and entrusted to a qualified unit according to law
Line processing.
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