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HJ 597-2011 English PDF

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HJ 597-2011: Water quality. Determination of total mercury. Cold atomic absorption spectrophotometry
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Standard similar to HJ 597-2011

GB 5085.7   HJ 609   GB 5085.1   HJ 599   HJ 600   HJ 598   

Basic data

Standard ID HJ 597-2011 (HJ597-2011)
Description (Translated English) Water quality. Determination of total mercury. Cold atomic absorption spectrophotometry
Sector / Industry Environmental Protection Industry Standard
Classification of Chinese Standard Z16
Classification of International Standard 13.060
Word Count Estimation 13,174
Date of Issue 2011-02-10
Date of Implementation 2011-06-01
Older Standard (superseded by this standard) GB/T 7468-1987
Regulation (derived from) Department of Environmental Protection Notice No. 9 of 2011
Issuing agency(ies) Ministry of Ecology and Environment
Summary This standard specifies the determination of total mercury cold vapor atomic absorption spectrophotometry. This standard applies to surface water, groundwater, industrial wastewater and domestic sewage in the determination of total mercury. If the organic matter content is high, the standard specifies the maximum amount of digestion reagent sufficient organic matter oxidation of the sample, this standard does not apply.

HJ 597-2011: Water quality. Determination of total mercury. Cold atomic absorption spectrophotometry


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Water quality.Determination of total mercury.Cold atomic absorption spectrophotometry National Environmental Protection Standard of the People's Republic Replace GB 7468-87 Determination of total mercury in water quality Cold atomic absorption spectrophotometry Water quality-Determination of total mercury -Cold atomic absorption spectrophotometry Published on.2011-02-10 2011-06-01 Implementation Ministry of Environmental Protection released Ministry of Environmental Protection announcement No. 9 of.2011 In order to implement the "Environmental Protection Law of the People's Republic of China", protect the environment, protect human health, and standardize environmental monitoring, the water is now approved. The determination of total mercury is determined by the Cold Atomic Absorption Spectrophotometry and other nine standards for national environmental protection standards. The standard name and number are as follows. 2. Determination of water quality ladders by sodium sulfite spectrophotometry (HJ 598-2011); 3. Determination of water quality ladders N-chlorohexadecylpyridine-sodium sulfite spectrophotometry (HJ 599-2011); 4. Gas chromatographic method (HJ 600-2011) for the determination of water quality ladders, black ropes, and dien ladders; 5. Determination of water quality of formaldehyde - Acetylacetone spectrophotometry (HJ 601-2011); 6. Determination of water quality 石墨 Graphite furnace atomic absorption spectrophotometry (HJ 602-2011); VII. Determination of water quality 火焰 Flame atomic absorption spectrophotometry (HJ 603-2011); VIII. Determination of total hydrocarbons in ambient air - Gas chromatography (HJ 604-2011); IX. Determination of Volatile Organic Compounds in Soils and Sediments Purge and Trap/Gas Chromatography-Mass Spectrometry (HJ 605-2011). The above standards have been implemented since June 1,.2011 and published by the China Environmental Science Press. The standard content can be found on the website of the Ministry of Environmental Protection. From the date of implementation of the above standards, the following seven national environmental protection standards approved and issued by the former National Environmental Protection Agency shall be abolished. The name and number are as follows. 1. Determination of total mercury in water quality by cold atomic absorption spectrophotometry (GB 7468-87); 2. Determination of water quality ladders by sodium sulfite spectrophotometry (GB/T 13905-92); 3. Determination of water quality ladders by spectrophotometry (GB/T 13903-92); 4. Determination of water quality TNT, Hessian and Dien, gas chromatography (GB/T 13904-92); V. Determination of water quality formaldehyde acetylacetone spectrophotometry (GB 13197-91); VII. Determination of total hydrocarbons in ambient air Gas chromatography (GB/T 15263-94). Special announcement. February 10,.2011

Content

Foreword..iv 1 Scope..1 2 Terms and definitions.1 3 method principle..1 4 Interference and elimination.1 5 Reagents and materials.1 6 instruments and equipment.3 7 samples.3 8 Analysis steps..5 9 result calculation and representation..5 10 Precision and Accuracy 6 11 Quality Assurance and Quality Control.7 12 Waste treatment 7 13 Notes 7 Appendix A (informative) Closed reaction device 8 Iv

Foreword

To protect the environment and protect the human body 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 Water Pollution Prevention and Control This standard is formulated for the determination of health and normal mercury in water. This standard specifies cold atomic absorption spectrophotometry for the determination of total mercury in surface water, groundwater, industrial wastewater and domestic sewage. This standard is a revision of the "Measurement of total mercury in water by cold atomic absorption spectrophotometry" (GB 7468-87). This standard was first published in 1987. The original standard drafting unit was Hunan Environmental Protection Monitoring Station. This is the first revision. Revision The main contents are as follows. -- Increased method detection limits; - increased interference and elimination clauses; - Added pretreatment method for microwave digestion; -- Added quality assurance and quality control provisions; -- Added provisions for waste disposal and precautions. The national environmental protection standard “Water quality approved and issued by the former National Environmental Protection Agency on March 14, 1987 since the implementation of this standard. Determination of total mercury by cold atomic absorption spectrophotometry (GB 7468-87) abolished. Appendix A of this standard is an informative annex. This standard was formulated by the Science and Technology Standards Department of the Ministry of Environmental Protection. This standard is mainly drafted by. Dalian Environmental Monitoring Center. This standard is verified by. Shenyang Environmental Monitoring Center Station, Anshan Environmental Monitoring Center Station, Fushun Environmental Monitoring Center Station, Dandong Municipal Environmental Monitoring Center Station, Changchun Environmental Monitoring Center Station and Harbin Environmental Monitoring Center Station. This standard was approved by the Ministry of Environmental Protection on February 10,.2011. This standard has been implemented since June 1,.2011. This standard is explained by the Ministry of Environmental Protection. Water quality - Determination of total mercury - Cold atomic absorption spectrophotometric method Warning. Potassium dichromate, mercury and their compounds are very toxic. Ventilation should be strengthened during operation. Operators should wear protective equipment to avoid contact. Touch the skin and clothing.

1 Scope of application

This standard specifies the cold atomic absorption spectrophotometric method for the determination of total mercury in water. This standard applies to the determination of total mercury in surface water, groundwater, industrial wastewater and domestic sewage. If the organic content is high, this standard This standard does not apply when the maximum amount of digesting reagent is insufficient to oxidize the organic matter in the sample. Using potassium permanganate-potassium persulfate digestion method and potassium bromate-potassium bromide digestion method, when the sampling amount is 100 ml, the detection limit is 0.02 μg/L. The lower limit of determination is 0.08 μg/L; when the sample volume is.200 ml, the detection limit is 0.01 μg/L, and the lower limit of determination is 0.04 μg/L. Microwave elimination Solution, when the sample volume is 25 ml, the detection limit is 0.06 μg/L, and the lower limit of determination is 0.24 μg/L.

2 Terms and definitions

The following terms and definitions apply to this standard. Total mercury total mercury Refers to mercury measured after digestion of unfiltered samples, including inorganic and organic mercury.

3 Principle of the method

Digestion of the sample with potassium permanganate and potassium persulfate in a sulfuric acid-nitric acid medium under heating; or with potassium bromate-potassium bromide mixture The sample is digested in a sulfuric acid medium; or the sample is digested with a microwave digestion apparatus in a nitric acid-hydrochloric acid medium. All the mercury contained in the digested sample is converted into divalent mercury, and the excess oxidant is reduced with hydroxylamine hydrochloride, and then the divalent value is determined by stannous chloride. Mercury is reduced to metallic mercury. The metal mercury is vaporized by introducing air or nitrogen at room temperature and loaded into a cold atomic absorption mercury analyzer at 253.7 nm. The strength is measured in response, and the mercury content is proportional to the response.

4 interference and elimination

4.1 Digestion of the sample by potassium permanganate-potassium persulfate digestion method. In the 0.5 mol/L hydrochloric acid medium, the ions in the sample exceed the following masses. At the concentration, ie, Cu2 500 mg/L, Ni2 500 mg/L, Ag 1 mg/L, Bi3 0.5 mg/L, Sb3 0.5 mg/L, Se4 0.05 mg/L, As5 0.5 mg/L, I− 0.1 mg/L, interfered with the assay. The interference of these ions can be eliminated by appropriately diluting the sample with water (5.1). 4.2 Digestion of the sample by potassium bromate-potassium bromide method. When the mass concentration of the detergent is greater than or equal to 0.1 mg/L, the recovery rate of mercury is less than 67.7%.

5 reagents and materials

Unless otherwise stated, analytically pure reagents that meet national standards were used for the analysis, and the experimental water was mercury-free water. 5.1 Mercury-free water. generally use double-distilled water or deionized water, or acidify to pH=3 with hydrochloric acid (5.4), and then pass through the sulfhydryl group. Cotton fiber tube (5.11.1) ordinary distilled water after mercury removal. 5.2 Potassium dichromate (K2Cr2O7). excellent grade pure. 5.3 concentrated sulfuric acid. ρ (H2SO4) = 1.84 g/ml, excellent grade pure. 5.4 Concentrated hydrochloric acid. ρ (HCl) = 1.19 g/ml, excellent grade pure. 5.5 concentrated nitric acid. ρ (HNO3) = 1.42 g/ml, excellent grade pure. 5.6 Nitric acid solution. 1 1. Measure 100 ml of concentrated nitric acid (5.5) and slowly pour into 100 ml of water (5.1). 5.7 Potassium permanganate solution. ρ(KMnO4) = 50 g/L. Weigh 50 g of potassium permanganate (excellent grade, recrystallized if necessary) dissolved in a small amount of water (5.1). Then use water (5.1) to bring up to 1 000 ml. 5.8 Potassium Persulfate Solution. ρ(K2S2O8) = 50 g/L. Weigh 50 g of potassium persulfate dissolved in a small amount of water (5.1). Then make up to 1 000 ml with water (5.1). 5.9 Potassium bromate-potassium bromide solution (abbreviated as brominating agent). c (KBrO3) = 0.1 mol/L, ρ (KBr) = 10 g/L. Weigh 2.744 g of potassium bromate (precious grade) dissolved in a small amount of water (5.1) and add 10 g of potassium bromide. Diluted with water (5.1) after dissolution To 1 000 ml, store in a brown reagent bottle. If bromine is released, it should be reconstituted. 5.10 巯 base cotton fiber. In a brown ground jar, 100 ml of thioglycolic acid (CH2SHCOOH), 60 ml of acetic anhydride [(CH3CO)2O], 40 ml of 36% acetic acid (CH3COOH), 0.3 ml of concentrated sulfuric acid (5.3), mix well, cool to room temperature, add 30 g of long fiber defatting Cotton, flattened, soaked completely, cooled with water, after the heat generated by the reaction is dissipated, capped, placed in an oven at (40 ± 2) °C for 2 to 4 d Remove afterwards. Filter with an acid-proof filter, wash thoroughly with water (5.1) until neutral, spread, and dry at 30-35 °C. Finished product in brown Color-grinding jars are stored in the dark at low temperatures. 5.11 Hydroxylamine hydrochloride solution. ρ(NH2OH·HCl) =.200 g/L. Weigh.200 g of hydroxylamine hydrochloride dissolved in an appropriate amount of water (5.1), and then make up to 1 000 ml with water (5.1). This solution often contains mercury, Should be purified. When the mercury content is low, the mercapto-based cotton fiber tube is used for mercury removal; when the mercury content is high, the mercury is removed by the extraction and mercury removal method. The mercury is removed by mercury removal by sulphur-based cotton fiber tube. 5.11.1 Mercury-based cotton fiber tube mercury removal method. a glass tube with an inner diameter of 6 to 8 mm and a length of about 100 mm, one end of which is thinned, or a liquid leakage of 500 ml Fill the liquid pipe with 0.1 to 0.2 g of sulfhydryl cotton fiber (5.10), and pass the reagent to be purified at a rate of 10 ml/min for one to two times. Do not use mercury. 5.11.2 Extraction and mercury removal method. Measure 250 ml of hydroxylamine hydrochloride solution (5.11) and pour into 500 ml separatory funnel, add 0.1 g/L double each time. 15 ml of a solution of thioindigo (C13H12N4S) in carbon tetrachloride (CCl4), and repeatedly extracting until the solution of dithionide-containing carbon tetrachloride is maintained. Green is unchanged. It is then extracted with carbon tetrachloride to remove excess dithizone. 5.12 Stannous chloride solution. ρ(SnCl2) =.200 g/L. Weigh 20 g of stannous chloride (SnCl 2 · 2H 2 O) in a dry beaker, add 20 ml of concentrated hydrochloric acid (5.4), and heat slightly. Waiting After complete dissolution, cool and dilute to 100 ml with water (5.1). If it contains mercury, it can be removed by nitrogen or air. 5.13 Potassium dichromate solution. ρ (K2Cr2O7) = 0.5 g/L. Weigh 0.5 g of potassium dichromate (5.2) dissolved in 950 ml of water (5.1) and add 50 ml of concentrated nitric acid (5.5). 5.14 Mercury standard stock solution. ρ (Hg) = 100 mg/L. Weigh 0.135 4 g of mercuric chloride (HgCl2) thoroughly dried in a silica gel drier, dissolved in potassium dichromate solution (5.13), and transferred. Into a 1 000 ml volumetric flask, dilute to the mark with potassium dichromate solution (5.13) and mix. A certified standard solution can also be purchased. 5.15 Mercury standard intermediate. ρ(Hg) = 10.0 mg/L. Measure 10.00 ml of mercury standard stock solution (5.14) into a 100 ml volumetric flask. Dilute to the mark with potassium dichromate solution (5.13), mix uniform. 5.16 Mercury standard use solution I. ρ (Hg) = 0.1 mg/L. Measure 10.00 ml of mercury standard intermediate (5.15) into a 1 000 ml volumetric flask. Dilute to the mark with potassium dichromate solution (5.13). Mix well. It can be placed in a cool place at room temperature for about 100 days. 5.17 Mercury standard use liquid II. ρ (Hg) = 10 μg/L. Measure 10.00 ml of mercury standard use solution I (5.16) into a 100 ml volumetric flask. Dilute to the mark with potassium dichromate solution (5.13). Mix well. Available now. 5.18 Diluent. Weigh 0.2 g of potassium dichromate (5.2) dissolved in 900 ml of water (5.1), then add 27.8 ml of concentrated sulfuric acid (5.3), diluted with water (5.1) Released to 1 000 ml. 5.19 Instrument wash. 10 g of potassium dichromate (5.2) was weighed and dissolved in 9 L of water, and 1 000 ml of concentrated nitric acid (5.5) was added.

6 Instruments and equipment

6.1 Cold Atomic Absorption Mercury Analyzer with hollow cathode lamp or electrodeless discharge lamp. 6.2 Reaction device. a total volume of 250 ml, 500 ml, with a ground, glass blister bottle with a shower-shaped porous blowing head, or with an instrument Matching reaction unit. Note. Lower levels of mercury can be measured using a closed reaction unit. See Appendix A for details of the reaction unit. 6.3 Microwave Digestion Apparatus. It has a temperature program. 6.4 Adjustable temperature electric heating plate or high temperature electric furnace. 6.5 Constant temperature water bath. The temperature control range is from room temperature to 100 °C. 6.6 Microwave digestion tank. 6.7 Vials. 500 ml, 1 000 ml, borosilicate glass or high density polyethylene. 6.8 Common instruments and equipment used in general laboratories.

7 samples

7.1 Sample collection and preservation 7.1.1 When collecting water samples, the sample should be filled as much as possible to reduce the wall adsorption. Industrial wastewater and domestic sewage sample collection should not For less than 500 ml, the collection of surface water and groundwater samples should be no less than 1 000 ml. 7.1.2 Immediately after sampling, the water sample should be fixed with 10 ml of concentrated hydrochloric acid (5.4) per liter of water sample. The pH of the water sample after fixation is fixed. The value should be less than 1, otherwise the amount of concentrated hydrochloric acid (5.4) should be increased appropriately, then 0.5 g of potassium dichromate (5.2) should be added. Appropriate addition of potassium dichromate (5.2), so that the water sample is a long-lasting light orange, dense, and shake. Store in a cool place at room temperature for 1 month. 7.2 Preparation of samples According to the characteristics of the sample, the following three methods can be selected to prepare the sample. 7.2.1 Potassium permanganate-potassium persulfate digestion 7.2.1.1 Near-boiling insulation method The digestion method is applicable to surface water, groundwater, industrial wastewater and domestic sewage. 7.2.1.1.1 After shaking the sample, take 100.0 ml of the sample and transfer it into a 250 ml Erlenmeyer flask. If the mercury content of the sample is high, the sampling can be reduced. Measure and dilute to 100 ml. 7.2.1.1.2 Add 2.5 ml of concentrated sulfuric acid (5.3), 2.5 ml of nitric acid solution (5.6) and 4 ml of potassium permanganate solution (5.7), and shake well. If it can't keep purple within 15 min, you need to add appropriate potassium permanganate solution (5.7) to keep the color purple, but potassium permanganate solution. The total amount does not exceed 30 ml. Then, 4 ml of potassium persulfate solution (5.8) was added. 7.2.1.1.3 Insert the funnel, place it in a boiling water bath for 1 h in the near-boiling state, and remove the cooling. 7.2.1.1.4 Before the measurement, add hydroxylamine hydrochloride solution (5.11) while shaking until the excess potassium permanganate and the wall on the wall are just oxidized. Manganese is completely faded until it is tested. Note. When measuring surface water or groundwater, measure.200.0 ml water sample into a 500 ml Erlenmeyer flask, and then add 5 ml concentrated sulfuric acid (5.3), 5 ml nitric acid. Solution (5.6) and 4 ml potassium permanganate solution (5.7), shake well. Other operations follow the above steps. 7.2.1.2 boiling method The digestion method is applicable to industrial wastewater and domestic sewage containing a large amount of organic matter and suspended solids. 7.2.1.2.1 Take the sample according to 7.2.1.1.1 and add the reagent according to 7.2.1.1.2. 7.2.1.2.2 Add a few glass beads or zeolite to the Erlenmeyer flask, insert the funnel, dry the bottom of the bottle, and then use a high temperature electric furnace or a thermostat Heat and boil for 10 min, remove and cool. 7.2.1.2.3 Operate in accordance with 7.2.1.1.4. 7.2.2 Potassium bromate-potassium bromide digestion The digestion method is applicable to surface water and groundwater, and is also applicable to industrial wastewater and domestic sewage containing less organic matter (especially detergent). 7.2.2.1 After shaking the sample, take 100.0 ml of the sample and transfer it to a 250 ml stoppered polyethylene bottle. If the mercury content of the sample is high, it can be reduced Sample and dilute to 100 ml. 7.2.2.2 Add 5 ml concentrated sulfuric acid (5.3), 5 ml brominating agent (5.9), add stopper, shake well, and let stand at room temperature above 20 °C for more than 5 min. Orange-brown bromine should be released from the test solution, otherwise the brominating agent (5.9) may be added as appropriate. However, the maximum amount per 100 ml of sample should not exceed 16 ml. If there is still no bromine release, the digestion method is not applicable and can be digested using 7.2.1.2 or 7.2.3. 7.2.2.3 Before the measurement, reduce the excess bromine by adding hydroxylamine hydrochloride solution (5.11) while shaking until the excess bromine is completely discolored. To be tested. Note. When measuring surface water or groundwater, take.200.0 ml of the sample and place it in a 500 ml Erlenmeyer flask, and then add 10 ml of concentrated sulfuric acid (5.3) and 10 ml. Bromine agent (5.9). Other operations follow the above steps. 7.2.3 Microwave digestion The method is applicable to industrial wastewater and domestic sewage containing more organic materials. 7.2.3.1 After shaking the sample, take 25.0 ml of the sample and transfer it to the microwave digestion tank. If the mercury content in the sample is high, the sample volume can be reduced and diluted. Release to 25 ml. 7.2.3.2 Add 2.5 ml concentrated nitric acid (5.5) and 2.5 ml concentrated hydrochloric acid (5.4) in turn, shake well, add stopper, and let stand at room temperature for 30-60 min. If the reaction is severe, the standing time is appropriately extended. 7.2.3.3 Place the microwave digestion vessel in the microwave digestion apparatus and digest according to the temperature rise procedure recommended in Table 1. After the digestion is completed, cool down to Transfer the digestion solution to a 100 ml volumetric flask at room temperature and dilute to the mark with the diluent (5.18) for testing. Table 1 Microwave digestion temperature program Step maximum power / power/ Heating time/ Min temperature/ Hold time / Min 1 1.200 100 5 120 2.00 2 1.200 100 5 150 2.00 3 1.200 100 5 180 5.00 7.3 Preparation of blank samples Replace the sample with water (5.1), prepare a blank sample according to the procedure of 7.2, and take into account the amount of reagent added during sampling.

8 Analysis steps

8.1 Instrument Commissioning Commission according to the instrument manual. 8.2 Drawing of the calibration curve 8.2.1 Drawing of high quality concentration calibration curve 8.2.1.1 Measure 0.00, 0.50, 1.00, 1.50, 2.00, 2.50, 3.00 and 5.00 ml of mercury standard use solution I (5.16), respectively In a 100 ml volumetric flask, dilute to the mark with a diluent (5.18). The total mercury mass concentrations are 0.00, 0.50, 1.00, 1.50, 2.00, respectively. 2.50, 3.00 and 5.00 μg/L. 8.2.1.2 Move the above standard series to 250 ml reactor, add 2.5 ml of stannous chloride solution (5.12), and insert it quickly. The gas head measures the response from a low mass concentration to a high mass concentration. The zero-mass concentration correction response value is the ordinate, and the corresponding total mercury mass is rich. The degree (μg/L) is plotted on the abscissa and a calibration curve is drawn. Note. The high-quality concentration calibration curve is suitable for the determination of industrial wastewater and domestic sewage. 8.2.2 Drawing of low mass concentration calibration curve 8.2.2.1 Measure the 0.00, 0.50, 1.00, 2.00, 3.00, 4.00 and 5.00 ml mercury standard solution II (5.17) in.200 ml capacity In the measuring flask, the volume is adjusted to the mark with the diluent (5.18), and the total mercury concentration is 0.000, 0.025, 0.050, 0.100, 0.150, 0.200. And 0.250 μg/L. 8.2.2.2 Move the above standard series to a 500 ml reaction unit in turn, add 5 ml of stannous chloride solution (5.12), and insert the insufflation quickly. The head measures the response from a low mass concentration to a high quality concentration. Correct the response value to the ordinate with zero mass concentration, corresponding to the total mercury mass concentration (μg/L) is the abscissa and a calibration curve is drawn. Note. The low mass concentration calibration curve is suitable for the determination of surface water and groundwater. 8.3 Determination When measuring industrial wastewater and domestic sewage samples, transfer the sample to be tested to a 250 ml reaction unit, and measure according to 8.2.1.2; For surface water and groundwater samples, the sample to be tested is transferred to a 500 ml reactor and measured according to 8.2.2.2. 8.4 Blank test The blank sample was measured in the same manner as the sample measurement.

9 Calculation and representation of results

9.1 Calculation of results The mass concentration ρ (μg/L) of total mercury in the sample was calculated according to the formula (1). 1 0 0 1 2V VV V V1 ρ ρρ − × = ×( ) (1) Where. ρ--the mass concentration of total mercury in the sample, μg/L; 1-1--calculate the mass concentration of total mercury in the sample according to the calibration curve, μg/L; Ρ0--calculate the mass concentration of total mercury in the blank sample according to the calibration curve, μg/L; V0--the constant volume of the standard series, ml; V1--sampling volume, ml; V2--When sampling, add concentrated hydrochloric acid volume to the water sample, ml; V--The sample volume is taken when preparing the sample, ml. 9.2 Results representation When the measurement result is less than 10 μg/L, it is retained to two decimal places; when it is greater than or equal to 10 μg/L, three significant figures are retained. 10 Precision and accuracy 10.1 Potassium Permanganate-Kilon Persulfate Digestion Method 47 laboratories measured uniform standard samples with a total mercury concentration of 0.58 μg/L, and the relative standard deviation in the laboratory. The relative standard deviations between th...

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