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how about zinc content

how about zinc content, Total:497 items.

In the international standard classification, how about zinc content involves: Water quality, Non-ferrous metals, Metalliferous minerals, Ferroalloys, Products of the chemical industry, Nuclear energy engineering, Wood, sawlogs and sawn timber, Semiconducting materials, Analytical chemistry, Testing of metals, Meat, meat products and other animal produce, Products of non-ferrous metals, Animal feeding stuffs, Wood-based panels, Iron and steel products, Wastes, Galvanic cells and batteries, Ferrous metals, Rubber, Fruits. Vegetables, Welding, brazing and soldering, Paint ingredients, Fertilizers, Non-metalliferous minerals, Surface treatment and coating, Paints and varnishes, Farming and forestry, Lubricants, industrial oils and related products, Textile fibres, Milk and milk products, Inorganic chemicals, Production of metals.

ZA-SANS, how about zinc content

SANS 5214:2005 Water - Zinc content
SANS 5214:2010 Water - Zinc content
SANS 5242:1971 Zinc content of white metal
SANS 5997:2004 Zinc detection in timber
SANS 383:2007 Standard test methods for zinc in water
SANS 9455-8:1991 Soft soldering fluxes - Test methods Part 8: Determination of zinc content

GM North America, how about zinc content

GM GM9738P-1988 Zinc Content of Zinc-Rich Primer

PL-PKN, how about zinc content

PN H04805-02-1991 Zinc powder Determination of total zinc content
PN H04805-03-1991 Zinc powder Determination of metallic zinc content
PN A04013-1959
PN H04805-04-1991 Zinc powder Determination of lead content
PN H04805-05-1991 Zinc powder Determination of cadmium content
PN H04805-06-1991 Zinc powder Determination of iron content
PN H04805-07-1991 Zinc powder Determination of copper content
PN H04805-08-1991 Zinc powder Determination of arsenic content
PN H04805-09-1991 Zinc powder Determination of antimony content
PN H04805-10-1991 Zinc powder Determination of tin content
PN C04596-02-1990 Water and waste water Tests for zinc Determination of zinc by zincon method
PN H04725-06-1991 Chemical analysis of foundry copper-base alloys Determination of zinc content
PN H04805-12-1991 Zinc powder Determination of chloride content
PN H04805-13-1991 Zinc powder Determination of sulfate content
PN C81700-1991 Paints and varnishes. The determination of zinc content in the anti-corrosive zinc paints
PN H04805-11-1991 Zinc powder Determination of acid insoluble matter content
PN R04016-1992 Agrochemical soil analyse. Determination of assimilated zink contents
PN C84081-48-1988 Salt (Sodium chloride) Determination of zinc Atomie absorption method
PN H04125-1992 Iron ores. Determination of lead and/or zinc content. Flame atomic absorption spectrometric method

RO-ASRO, how about zinc content

STAS 2979/5-1984 GOPPKK-TIX Ai.l.OYS Zinc content determinai iun
STAS 9144/2-1986 Zinc powder DETERMINATION OF METALLIC ZINC CONTENT
STAS 1776/7-1978 LEAD Determination of zinc content
STAS 1818/4-1984 ZINC Iron content dctcrmination
STAS 1818/5-1975 ZINC Determination of arsenic content
STAS 1818/6-1975 ZINC Determinations of antimony content
STAS 1818/8-1975 ZINC Determinations of aluminium content
STAS 7844-1967
STAS 7843-1967
STAS 7846-1967
STAS 7847-1967
STAS 1818/7-1975 ZINC Determination of tin content
STAS 1818/9-1975 ZINC Determination of magnesium content
STAS 9144/3-1986 ZINC POWDER Determination of cadmium content
STAS 2960/12-1967
STAS 3238/8-1976 ANTIMONOUS LEAD Determination of zinc content
STAS 9144/4-1986 ZING POWDER Determination of iron content
STAS 9144/5-1986 Zinc powder DETERMINATION -OF ARSENIC CONTENT
STAS 9144/6-1972 ZING POWDER Determination of lead content
STAS 9144/6-1986 Zinc powder. DETERMINATION OF LEAD CONTENT
STAS 7744-1967
STAS 8314-1987 WATER TREATMENT Determination of zinc content
STAS 7745-1967
STAS 7747-1967
STAS 6327-1969
STAS 6894-1963
STAS 1818/2-1975 ZINC Determination of lead and cadmium content
STAS 2979/9-1984 COFPKR-TIN ALLOYS Alumininrn content determination
STAS 7742/2-1975 ZINC ALLOYS Determination of aluminium content
STAS 7742/4-1975 ZINC ALLOYS Determination of magnesium content
STAS 7742/5-1975 ZINC ALLOYS Determination of iron content
STAS 7742/7-1975 ZINC ALLOYS Determination of tin content
STAS SR 13303-3-1995 Chlorous sludge Zinc content determination
STAS 2771/10-1970 WHITE METAL BEARING Al.LOYS Dt'tciiiihiation of zinc
STAS 2825/12-1967
STAS 7742/3-1975 ZINC ALLOYS Determination of copper content
STAS 7746-1967
STAS 7742/6-1975 ZINC ALLOYS Determination of lead and cadmium content
STAS 2615/9-1969
STAS SR 13209-1994 Chemical fertilizers with trace elements. Determination of zinc content
STAS 1314/27-1977 MANGANESE ORES AND CONCENTRATES Determination of zinc content
STAS 1574/10-1985 IRON ORES AND CONCENTRATES Determination of zinc content
STAS 2958/7-1971 LEAD BASE ANTIFR1CTI0N ALLOY YPb 98 Dctermination of zinc
STAS 7947/10-1988 CALCINED ALUMINUM OXIDE Zinc oxide content determination
STAS 8907/4-1981 SILVER AND SILVER ALLOYS Determination of silver, zinc, copper and cadmium content
STAS 1269/4-1989 COPPER, LEAD, ZING, BISMUTH, MOLYBDENUM, PYRITE AND COMPLEX SULPHURE ORES AND CONCENTRATES Zinc content determination
STAS 7717-1981 ADDlTIVES AND OILS WITH DDITIVES Deternination of zinc content
STAS 96-1987 Metals soldering SOFT SOLDHRS WITH TIN, I.EAD, CADMIUM AND ZINC CONTHNT
STAS SR EN 29455-8-1994 Soft soldering fluxes. Test methods. Part 8: Determination of zinc content
STAS SR 13255-1-1995 Nonferrous ores and concentrates.Cyanided leachs Determination of zinc content
STAS 12516/1-1992 Cooper, lead, zinc ores, pyrite and complex sulphides. Determination of zinc content from some mineralogical elements. Rational analysis
STAS 11427-1980 VULCANIZED RUBBER Determination of zinc content EDTA titrimetric method

RU-GOST R, how about zinc content

GOST 24978-1991 Copper-zinc alloys. Methods for determination of zinc
GOST 16274.7-1977 Bismuth. Method for determination of zinc content
GOST 12645.7-1977 Indium. Method for determination of zinc
GOST 15483.9-1978 Tin. Methods for determination of zinc
GOST 19251.1-1979 Zinc. Method of iron determination
GOST 19251.3-1979 Zinc. Method of copper determination
GOST 19251.4-1979 Zinc. Method of arsenic determination
GOST 19251.5-1979 Zinc. Methods of tin determination
GOST 19251.6-1979 Zinc. Methods of antimony determination
GOST 20580.3-1980 Lead. Method for the determination of zinc
GOST 13047.11-2002 Nickel. Cobalt. Method for determination of zinc
GOST 15933.17-1970 Ferroniobium. Method for the determination of zinc content
GOST 13047.11-1981 Nickel. Methods for the determination of bismuth
GOST 13583.9-1993 Alumina. Methods for the determination of zinc oxide
GOST 25284.2-1995 Zinc alloys. Methods for determination of copper
GOST 25284.3-1995 Zinc alloys. Methods for determination of magnesium
GOST 25284.4-1995 Zinc alloys. Methods for determination of lead
GOST 25284.5-1995 Zinc alloys. Methods for determination of cadmium
GOST 25284.6-1995 Zinc alloys. Methods for determination of iron
GOST 25284.7-1995 Zinc alloys. Methods for determination of tin
GOST 14048.17-1977 Zinc concentrates. Method for the determination of indium
GOST 19251.2-1979 Zinc. Method of cadmium and lead determination
GOST 22519.5-1977 Thallium. Method for the determination of copper, cadmium and zink
GOST 25284.2-1982 Zinc alloys. Methods for the determination of copper
GOST 25284.3-1982 Zinc alloys. Methods for the determination of magnesium
GOST 25284.4-1982 Zinc alloys. Methods for the determination of lead
GOST 25284.5-1982 Zinc alloys. Methods for the determination of cadmium
GOST 25284.6-1982 Zinc alloys. Methods for the determination of iron
GOST 25284.7-1982 Zinc alloys. Method for the determination of tin
GOST 1652.1-1977 Copper-zinc alloys. Methods for the determination of copper
GOST 1652.2-1977 Copper-zinc alloys. Methods for the determination of lead
GOST 1652.3-1977 Copper-zinc alloys. Methods for the determination of iron
GOST 1652.4-1977 Copper-zinc alloys. Methods for the determination of manganese
GOST 1652.5-1977 Copper-zinc alloys. Methods for the determination of tin
GOST 1652.6-1977 Copper-zinc alloys. Methods for the determination of antimony
GOST 1652.7-1977 Copper-zinc alloys. Methods for the determination of bismuth
GOST 1652.8-1977 Copper-zinc alloys. Methods for the determination of arsenic
GOST 1652.9-1977 Copper-zinc alloys. Methods for the determination of sulphur
GOST 1652.10-1977 Copper-zinc alloys. Methods for the determination of aluminium
GOST 1652.11-1977 Copper-zinc alloys. Methods for the determination of nickel
GOST 1652.12-1977 Copper-zinc alloys. Methods for the determination of silicon
GOST 1652.13-1977 Copper-zinc alloys. Methods for the determination of phosphorus
GOST 21877.8-1976 Tin and lead babbits. Methods for the determination of zinc
GOST 18293-1972 Drinking water. Methods for determination of lead, zinc and silver content
GOST 13637.2-1993 Gallium. Atomic-emission method for the determination of cadmium, lead, zinc
GOST 23957.2-2003 Zinc. Atomic-absorption method for determination of tin
GOST 1762.7-1971 Aluminium-silicon alloy ingots. Methods for determination of zinc
GOST 2082.12-1981 Molibdenum concentrates. Method for determination of zinc contents
GOST 13151.8-1977 Ferromolybdenum. Methods for the determination of zinc, lead and bismuth content
GOST 15934.2-1980 Copper concentrates. Methods for determination of lead, zinc and cadmium
GOST 20997.3-1981 Thallium. Method of spectral determination of cadmium and zinc
GOST 22221.5-1976 Tin concentrates. Methods for the determination of copper and zink mass part
GOST 24938-1985 Zinc concentrates. Spectrographic method for determination of gallium, germanium, indium, arsenic, tin, stibium, thallium
GOST 27996-1988 Vegetable feeds. Methods for determination of zink
GOST 23957.2-1980 Zinc. Atomic-absorbic method for the determination of tin
GOST 13637.2-1977 Gallium. Spectral method for the determination of cadmium, lead and zinc
GOST 14048.4-1978 Zinc concentrates. Methods for determination of silicon dioxide
GOST 14048.11-1980 Zinc concentrates. Method for the determination of calcium oxide, magnesium oxide and aluminium oxide
GOST R 57532-2017 Dusts of non-ferrous metallurgy enterprises. Methods of zinc mass content measuring
GOST 14047.2-1978 Lead concentrates. Determination of copper and zinc by polarographic, complexometric and atomic absorption methods
GOST 25363-1982 Zinc concentrates. Atomic-absorption methods for the determination of gold and silver contents
GOST 26100-1984 Copper concentrates. Determination of lead, zinc, cadmium. Flame atomic absorption method
GOST 11739.24-1998 Aluminium casting and wrought alloys. Methods for determination of zinc
GOST 11739.24-1982 Aluminium casting and deformable alloys. Methods for determination of zinc
GOST 23581.7-1979 Iron ores, concentrates, agglomerates and pellets. Methods of the determination of zinc and lead content
GOST 12362-1979 Alloy and high-alloy steels. Methods for determination of stibium, lead, tin, zinc and cadmium
GOST 13538-1968 Additives and lubricating oils with additives. Method for determination of barium, calcium and zinc contents by complexonometric titration
GOST 21979-1976 Reagents. Zinc compounds. Polarographic method for the determination of copper, lead and cadmium as impurities
GOST 33904-2016 Lubricating oils. Determination of barium, calcium, magnesium and zinc content by method of atomic absorption spectrometry
GOST 21639.11-1976 Flux for electroslag remelting. Method for the determination of lead, zinc, titanium, antimony

CZ-CSN, how about zinc content

CSN 44 1780-1977 Zinc concentrates. Complexometric determination of zinc
CSN 65 4845-1983 Fertilizers wlth microelements. Testlng of zinc content
CSN 44 1672-1989 Zinc concentrates. Determination of arsenic content
CSN 44 1624-1989 Lead - zinc ores. Polarographic and atomic absorption methods of determination of zinc
CSN 44 1622-1989 Lead - zinc ores. Gravimetric method of determination of silicon dioxide
CSN 44 1664-1989 Zinc concentrates. Determination of sulphur content
CSN 44 1674-1989 Zinc concentrates. Determination of indium content
CSN 44 1665-1989 Zinc concentrates. Determination of iron content
CSN 44 1340-2004 Lead-zinc ores. Photometric method of determination of germanium
CSN 44 1673-1989 Zinc concentrates. Determination of gallium content
CSN 44 1632-1989 Lead - zinc ores. Photometric method of determination of germanium
CSN 44 1627-1989 Lead - zinc ores. Potentiometric method of determination of arsenic
CSN 44 1675-1989 Zinc concentrates. Determination of germanium content
CSN 42 0630 Cast.8-1984 Chemical analysis of non-ferrous metals and alloys. Zinc alloys. Determination of tin by the photometric method
CSN 44 1629-1989 Lead - zinc ores. Titrimetric method of determination of iron content
CSN 44 1669-1989 Zinc concentrates. Determination of cadmium content
CSN 44 1626-1989 Lead - zinc ores. Atomic absorption method of determination of cadmium
CSN 44 1631-1989 Lead - zinc ores. Atomic absorption method of determination of silver
CSN 44 1667-1989 Zinc concentrates. Determination of aluminium oxide content
CSN 44 1666-1989 Zinc concentrates. Determination of silicon dioxide content
CSN 05 1021 Cast.14-1988 Welding.Analysis of aerosols generated in wel- ding. Determination of zinc content
CSN 44 1630-1989 Lead - zinc ores. Determination of sulphur
CSN 44 1662-1989 Zinc concentrates. Determination of copper content
CSN 44 1732-1989 Molybdenum concentrates. Determination of zinc
CSN 44 1661-1989 Zinc concentrates. Determination of lead content
CSN 44 1628-1989 Lead - zinc ores. Polarographic and atomic absorption methods of determination of antimony
CSN 44 1623-1989 Lead - zinc ores. Polarographic and atomic absorption methods of determination of lead
CSN 44 1670-1989 Zinc concentrates. Determination of cobalt content
CSN 44 1663-1989 Zinc concentrates. Determination of antimony content
CSN 44 1625-1989 Lead - zinc ores. Polarographic and atomic absorption methods of determination of copper
CSN 44 1671-1989 Zinc concentrates. Determination of manganese content
CSN 46 7092-16-1998 Testing methods for feeding stuffs - Part 16: Determination of copper, iron, manganese and zinc content
CSN ISO 4740:1992 Copper and copper alloys — Determination of zinc content — Fláme atomic absorption spectrometric method
CSN ISO 5194:1992 Aluminium and aluminium alloys - Determination of zinc content - Flame atomic absorption apectrometric method

AENOR, how about zinc content

UNE 48292:2005 Metallic zinc content in zinc rich paints.
UNE 37254:1986 LEAD. DETERMINATION OF ZINC CONTENT. SPECTROMETRIC METHOD ABSORPTION TECHNIQUE.
UNE 38173:1996 MAGNESIUM ALLOYS. DETERMINATION OF ZINC CONTENT. FLAME ATOMIC ABSORPTION SPECTROMETRIC METHOD.
UNE 7364:1978 DETERMINATION OF ZINC CONTENT IN IRON ORES, SLAGS AND LIMESTONES BY OMIC ABSORPTION METHOD.
UNE 7360:1978 DETERMINATION OF ZINC CONTENT IN IRON ORES, SLAGS AND LIMESTONES BY ATOMIC ABSORPTION METHOD.

HU-MSZT, how about zinc content

United States Navy, how about zinc content

NAVY MIL-P-21035 B REINST NOTICE 2-2003 PAINT HIGH ZINC DUST CONTENT, GALVANIZING REPAIR (METRIC)
NAVY MIL-P-21035 B-1991 PAINT HIGH ZINC DUST CONTENT, GALVANIZING REPAIR (METRIC)

International Organization for Standardization (ISO), how about zinc content

ISO 620:1975 Manganese ores — Determination of zinc content — Polarographic method (zinc content between 0,005 and 0,1 %)
ISO 551:1975 Manganese ores — Determination of zinc content — Zinc mercurithyocyanate gravimetric method
ISO 1169:1975 Zinc alloys; Determination of aluminium content; Volumetric method
ISO 1055:1975 Zinc and zinc alloys; Determination of iron content; Spectrophotometric method
ISO 1570:1975 Zinc and zinc alloys; Determination of tin content; Spectrophotometric method
ISO 1054:1975 Zinc; Determination of cadmium content; Polarographic method
ISO 715:1975 Zinc; Determination of lead content; Polarographic method
ISO 714:1975 Zinc; Determination of iron content; Photometric method
ISO 12739:2006 Zinc sulfide concentrates - Determination of zinc - Ion-exchange/EDTA titrimetric method
ISO 1976:1975 Zinc alloys — Determination of copper content — Electrolytic method
ISO 1169:2006 Zinc alloys - Determination of aluminium content - Titrimetric method
ISO 1053:1975 Zinc; Determination of copper content; Spectrophotometric method
ISO 713:1975 Zinc; Determination of lead and cadmium contents; Polarographic method
ISO 1784:1976 Aluminium alloys; Determination of zinc; EDTA titrimetric method
ISO 2454:1976 Title missing - Legacy paper document
ISO 3750:1976 Zinc alloys; Determination of magnesium content; Atomic absorption method
ISO 2454:1995 Rubber products - Determination of zinc content - EDTA titrimetric method
ISO 13658:2000 Zinc sulfide concentrates - Determination of zinc content - Hydroxide precipitation and EDTA titrimetric method
ISO 13543:1996 Copper, lead and zinc sulfide concentrates - Determination of mass of contained metal in a lot
ISO 6101-1:1991 Rubber; determination of metal content by atomic absorption spectrometry; part 1: determination of zinc content
ISO 6101-1:2019 Rubber — Determination of metal content by atomic absorption spectrometry — Part 1: Determination of zinc content
ISO/R 807:1968 Chemical analysis of magnesium and magnesium alloys — Polarographic determination of zinc (zinc content between 0.1 and 4 %)
ISO/R 798:1968 Chemical analysis of aluminium and its alloys — Gravimetric determination of zinc in aluminium alloys (zinc content between 0.50 and 6.5 %)
ISO 13543:2016 Copper, lead, zinc and nickel sulfide concentrates - Determination of mass of contained metal in a lot
ISO 9455-8:1991 Soft soldering fluxes; test methods; part 8: determination of zinc content
ISO 3750:2006 Zinc alloys - Determination of magnesium content - Flame atomic absorption spectrometric method
ISO 4194:1981 Magnesium alloys; Determination of zinc content; Flame atomic absorption spectrometric method
ISO 13310:1997 Iron ores - Determination of zinc content - Flame atomic absorption spectrometric method
ISO 6101-1:1981 Rubber; Determination of metal content; Flame atomic absorption spectrometric method; Part 1 : Determination of zinc content
ISO 11813:1998 Milk and milk products - Determination of zinc content - Flame atomic absorption spectrometric method
ISO 2454:1982 Rubber products; Determination of zinc content; EDTA titrimetric method
ISO 5194:1981 Aluminium and aluminium alloys; Determination of zinc content; Flame atomic absorption spectrometric method
ISO 4740:1985 Copper and copper alloys; Determination of zinc content; Flame atomic absorption spectrometric method
ISO 11813:2010 Milk and milk products - Determination of zinc content - Flame atomic absorption spectrometric method
ISO 11813:2010 | IDF 156:2010 Milk and milk products — Determination of zinc content — Flame atomic absorption spectrometric method
ISO 11813:2010|IDF 156:2010 Determination of zinc content in milk and dairy products by flame atomic absorption spectrometry
ISO 2072:1981 Aluminium oxide primarily used for the production of aluminium; Determination of zinc content; PAN photometric method
ISO 6636-1:1986 Fruits, vegetables and derived products; Determination of zinc content; Part 1 : Polarographic method

Japanese Industrial Standards Committee (JISC), how about zinc content

JIS H 1674:1992 Methods for determination of tungsten in zirconium and zirconium alloys
JIS M 8228:1997 Iron ores -- Methods for determination of zinc content
JIS M 8124:2003 Ores -- Methods for determination of zinc
JIS M 8124:1979 Methods for determination of zinc in ores
JIS H 1062:1989 Methods for determination of zinc in copper alloys
JIS H 1108:1989 Methods for determination of lead in zinc metal
JIS H 1109:1989 Methods for determination of iron in zinc metal
JIS H 1110:1989 Methods for determination of cadmium in zinc metal
JIS H 1111:1989 Methods for determination of tin in zinc metal
JIS H 1333:1991 Methods for determination of zinc in magnesium alloys
JIS H 1062 AMD 1:2013 Methods for determination of zinc in copper and copper alloys (Amendment 1)
JIS K 6232:1998 Rubber products -- Determination of zinc contents -- EDTA titrimetric method
JIS M 8083:2001 Copper, lead and zinc sulfide concentrates -- Sampling procedures and methods for determination of moisture content

Professional Standard - Nuclear Industry, how about zinc content

EJ/T 842-1994 Zinc Isotope Ratio and Zinc Content Measurement Double Dilution Mass Spectrometry
EJ/T 549-1991 Determination of Trace Zinc in Uranium-bearing Rocks by Oscillopolarography

VN-TCVN, how about zinc content

TCVN 2178-1987 Tin.Method for the determination of zinc content
TCVN 4292-1986 Iron ores.Determination of zinc and lead contents
TCVN 3647-1981 Tin ores.Method for the determination of copper and zinc contents
TCVN 7793-2007 Iron ores.Determination of zinc content.Flame atomic absorption spectrometric method

Indonesia Standards, how about zinc content

SNI 06-1137-1989 Water, Test methods for zinc content
SNI 07-1166-1989 Aluminium and aluminium alloys, Chemical test method for determination of zinc contents
SNI 07-1173-1989 Aluminium and aluminium alloys, Chemical test method for determination of zirconium contents

Korean Agency for Technology and Standards (KATS), how about zinc content

KS D 1938-2003 Determination of element content in zinc and zinc alloy
KS D 1938-2003(2013) Determination of element content in zinc and zinc alloy
KS D ISO 1055:2012 Zinc and zinc alloys－Determination of iron contentSpectrophotometric method
KS D ISO 1570:2012 Zinc and zinc alloys－Determination of tin content－Spectrophotometric method
KS D ISO 1054:2012 Zinc－Determination of cadmium content－Polarographic method
KS D ISO 714:2002 Zinc－Determination of iron content－Photometric method
KS D ISO 714-2002(2022) Zinc－Determination of iron content－Photometric method
KS D 1756-2009 Methods for determination of lead in zinc metal
KS D 1757-2009 Methods for determination of cadmium in zinc metal
KS D 1758-2005 Method for determination of tin in zinc metal
KS D ISO 715:2012 Zinc－Determination of lead content－Polarographic method
KS E ISO 12739:2007 Zinc sulfide concentrates－Determination of zinc content－Ion-exchange and EDTA titrimetric method
KS D ISO 1976:2002 Zinc alloys-Determination of copper content-Electrolytic method
KS D ISO 1169:2012 Zinc alloys－Determination of aluminum content－Titrimetric method
KS D ISO 1053-2002(2007) Zinc－Determination of copper content?Spectrophotometric method
KS D ISO 1169-2012(2022) Zinc alloys－Determination of aluminum content－Titrimetric method
KS E ISO 12739-2007(2022) Zinc sulfide concentrates－Determination of zinc content－Ion-exchange and EDTA titrimetric method
KS D ISO 713:2012 Zinc－Determination of lead and cadmium contents－Polarographic method
KS D 1884-2009 Determination of zinc in copper and copper alloys
KS E ISO 13291:2007 Zinc sulfide concentrates－Determination of zinc content－Solvent extraction and EDTA titrimetric method
KS M ISO 2454:2010 Rubber products－Determination of zinc content－EDTA titrimetric method
KS D 1869-2001 Determination of zinc in aluminium and aluminium alloys
KS D ISO 3750:2012 Zinc alloys－Determination of magnesium content－Flame atomic absorption spectrometric method
KS M ISO 2454-2010(2021) Rubber products－Determination of zinc content－EDTA titrimetric method
KS E ISO 13658-2012(2022) Zinc sulfide concentrates－Determination of zinc content－Hydroxide precipitation and EDTA titrimetric method
KS E ISO 13543:2003 Copper, lead and zinc sulfide concentrates－Determination of mass of contained metal in a lot
KS E ISO 13543:2020 Copper, lead, zinc and nickel sulfide concentrates —Determination of mass of contained metal in a lot
KS B ISO 9455-8:2004 Soft soldering fluxes－Test methods－Part 8：Determination of zinc content
KS B ISO 9455-8:2019 Soft soldering fluxes — Test methods — Part 8: Determination of zinc content
KS D ISO 1784:2001 Aluminium alloys-Determination of zinc-EDTA titrimetric method
KS E ISO 13310-2003(2018) Iron ores－Determination of zinc content－Flame atomic absorption spectrometric method
KS E ISO 13310:2003 Iron ores－Determination of zinc content－Flame atomic absorption spectrometric method
KS D ISO 4194:2002 Magnesium alloys－Determination of zinc content－Flame atomic absorption spectrometric method
KS H ISO 11813:2006 Milk and milk products－Determination of zinc content－Flame atomic absorption spectrometric method
KS H ISO 11813-2006(2016) Milk and milk products－Determination of zinc content－Flame atomic absorption spectrometric method
KS E ISO 9599:2018 Copper, lead, zinc and nickel sulfide concentrates — Determination of hygroscopic moisture content of the analysis sample — Gravimetric method
KS E ISO 12743-2008(2018) Copper, lead, zinc and nickel concentrates－Sampling procedures for determination of metal and moisture content

YU-JUS, how about zinc content

JUS C.A1.380-1988 Methods of chemical analysis of zine powder. Determination of metalic zine content. Volumetric me-thod
JUS H.G8.341-1988 Reagents. Zine cbloride. Deterainaticm of -zine oxide chloride ctmteut. Volumctric method
JUS H.P8.064-1988 Testing ofpesticides. Ziram, technical. Determination of zine content
JUS C.A1.353-1988 Zine. Determination of lead and cadmium contents. Polarographic method
JUS B.G8.355-1977 Zine concentrates. Methods of chemical analysis. Determination of lead
JUS H.G8.344-1988 Keagents. Zine cbloride. Determination of Iron cemtent. Colorimetric method
JUS H.G8.339-1988 Reagents. Zine cbloride. Deten~ination of zine chloride content. E?TA (disodium salt) complexometric method
JUS H.C8.222-1989 Pigments. Basic zine potassium chromat and zine tetrahvdroxvchromate. Determination of zine content (as ZnO). Volumetric method
JUS H.G8.343-1988 Reagents. Zine chloride. Determination of total nitrogen content. Colorinetcic metbod
JUS H.C8.216-1989 Pigment. Basic zine potassium chromate and zine tetrahvdroxvchromate. Determination of water-soluble chlorides content (as Cl). Volumetric method
JUS H.G8.447-1990 Reagents. Zine sulphate heptahydrate. Determination of total nitrogen content. Colorimetric method
JUS H.G8.022-1980 Reagents. Hydrochloric acid. Determination ofzinc content. Flame atomic absorption method
JUS H.G8.448-1990 Reagents. Zine sulphate heptahydrate. Determination of iron content. Colorimetric method
JUS H.G8.342-1988 Reagents. Zine chloride. ?etermination of sulphates content. Turbldimetric mc?hod
JUS B.G8.361-1977 Zine concentrates. Methods of chemical analysis. Determination of total sulphur
JUS H.G8.036-1981 Reagents. Sulphuric acid. Determination ofzinc content. Flame atomic absorption method
JUS H.G8.132-1984 Reagents. Ammonia solution. Determination of zine content. Flame atomic absorption method
JUS B.G8.363-1977 Zine concentrates. Methods of chemkalanalysis. Determination of calcium oxide
JUS B.G8.364-1977 Zine concentrates. Methods of chemkalanalysis. Determination of magnesium oxide
JUS H.G8.340-1988 Reagents. Zine cblori?e. Determination of substances insoluble in bjdzochloric acid. Gravimetric method
JUS H.G8.446-1990 Reagents. Zine sulphate heptahydrate? Determination of chlorides content. Turbidimetric method
JUS B.G8.362-1977 Zine concentrates. Methods of chemical anatysis. Determination of silica
JUS H.C8.218-1989 Pigments. Zine tetrahvdroxychromate. Determination of total matter soluble in water. Gravimetric method
JUS H.G8.444-1990 Reagents. Zine sulphate heptahydrate. Determination of substances insoluble in water. Gravimetric metho?
JUS H.C8.215-1989 Pigments. Basic zine potassium chromate and zine tetrahvdroxychromate. Determination of water-soluble sulphates content (as SO,). Gravimetric method
JUS H.G8.361-1988 Reagents. Zine chlori?e. Determinatioft of sodium and potassium contents. Flame atomic absorption method
JUS B.G8.372-1983 Ores and concentrates. Zine concentrate. Methods for chemical analysis. Determination of fluor
JUS H.C8.220-1989 Pigments. Basic zine Dotassium chromate and zine tetrahvdroxychromate. Determination of chromate content (as CrO,). Volumetric method
JUS H.G8.025-1980 Reagents. Hydrochhric acid. Determination of lead, copper, zine and cadmium contents. Anodic strip- ping voltammetry method
JUS H.G8.040-1981 Reagents. Sulphuric acid. Determination of lead, copper, zine and cadmium contents. Anodicstripping voltammetry method
JUS H.G8.130-1984 Reagents. Ammonia solution. Determination of iron content. 1,10—Phenanthrolinespectrophotometric method

TR-TSE, how about zinc content

TS 691-1969 METHODS OF CHEMICAL ANALYSIS OF MANGANESE ORES DETERMINATION OF ZINC CONTENT (Polarographic method, for zinc content from 0,005 to 0,1 °/o inclusive)
TS 3177-1978 ZINC ALLOYS — DETERMINATION OF MAGNESIUM CONTENT — ATOMIC ABSORPTION METHOD
TS 600-1968 METHODiS OF CHEMICAL ANALYSIS OF MANGANESE OBES DETERMINAT?ON OF ZING CONTENT
TS 3652-1981 METHODS FOR THE ANALYSIS OF WATER — DETERMINATION OF ZINC CONTENT — Zincon Spectrophotometry and Atomic Absorption Methods
TS 725-1969 CHEMICAL ANALYSIS OF ALUMINIUM AND ITSALLOYS GRAVIMETRTC DETERMINATION OF ZINC ?N ALUMINIUM ALLOYS (Zinc conlent bctween 0,50' - 6,5 %)

BE-NBN, how about zinc content

NBN P 32-002-1977 Zinc - Determination of iron content -photometric method
NBN P 32-005-1977 Zinc - Determination of cadmium content - Polarographic method
NBN P 32-003-1977 Zinc - Determination of lead content Polarographic method
NBN I-911-1968
NBN P 32-008-1977 Zinc and zinc alloys - Determination of tin content -Spectrophotometric method
NBN P 32-006-1977 (Zinc and zinc alloys - Determination of iron content Spectrophotometric method
NBN P 32-004-1977 Zinc - Determination of copper content -Spectrophotometric method
NBN P 32-007-1977 Zinc alloys - Determination of aluminium content Volumetric method
NBN P 32-009-1977 Zinc alloys - Determination of copper content -Electrolytic method
NBN P 32-001-1977 Zinc - Determination of lead and cadmium contents -Polarographic method
NBN P 32-010-1977 determination of lead and cadmium in zinc alloys containing copper
NBN T 95-401-1979 Determination of the lead, zinc, cadmium, copper, nickel ? and iron content of a gas flow
NBN P 32-012-1977 Zinc alloys - Determination of magnesium content -Atomic absorption method
NBN P 32-011-1977 Zinc alloys - Complexometric determination of magnesium
NBN-EN 29455-8-1993 Soft soldering fluxes. Test methods. Part 8: Determination of zinc content (ISO 9455-8: 1991)

General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China, how about zinc content

GB/T 9695.20-1990 Meat and meat products--Method for determination of zinc
GB 24428-2009 Limitation of mercury content for zinc silver oxide,zinc oxygen and zinc manganese dioxide button batteries
GB/T 11203-2001 Rubber--Determination of zinc content--EDTA titrimetric method
GB/T 12285-1990 Fruits,vegetables and derived products--Determination of zinc content
GB/T 12496.20-1999 Test methods of wooden activated carbon-Determination of zine content
GB/T 14540-2003 Determination of copper,iron,manganese,zinc,boron and molybdenum content for compound fertilizers
GB/T 4500-2003 Rubber--Determination of zinc content by atomic absorption spectrometry
GB/T 13748.15-2005 Chemical analysis methods of magnesium and magnesium alloys.Determination of zinc content
GB/T 38265.8-2022 Test methods for soft soldering fluxes—Part 8: Determination of zinc content
GB/T 16634-1996 Industrial circulating cooling water--Determination of zinc for phosphorus-zinc prefilming fluid--Atomic absorption spectrometric method
GB/T 6730.53-2004 Iron ores-Determination of zinc content-Flame atomic absorption spectrometric method
GB/T 13748.15-2013 Chemical analysis methods of magnesium and magnesium alloys.Part15:Determination of zinc content
GB/T 14637.1-1993 Industrial circulating cooling water--Determination of zinc--Atomic absorption spectrometry
GB/T 20975.8-2008 Methods for chemical analysis of aluminium and aluminium alloys.Part 8: Determination of zinc content
GB/T 5121.11-2008 Methods for chemical analysis of copper and copper alloys.Part 11:Determination of zinc content

Professional Standard - Agriculture, how about zinc content

GB 9695.20-1990 Determination of Zinc Content in Meat and Meat Products
GB 12285-1990 Determination of zinc content in fruits, vegetables and products
NY/T 1974-2010 Water-soluble fertilizers-Determination of copper, iron, manganese, zinc, boron, molybdenum content
NY 1500.56.4-2009 Maximum residue limits for pesticides.mancozeb.miscellaneous kinds of leguminous vegetable(include legume)

Association Francaise de Normalisation, how about zinc content

NF F19-217:1994 Railway rolling stock. High content of zinc coating.
NF A06-553:1966 Chemical analysis of aluminium and aluminium alloys. Determination of zinc.
NF A06-554:1966 Chemical analysis of aluminium and aluminium alloys. Polarogrpahic determination of zinc.
NF ISO 11813:2010 Lait et produits laitiers - Détermination de la teneur en zinc - Méthode par spectrométrie d'absorption atomique avec flamme
NF A06-841-8*NF EN 12441-8:2005 Zinc and zinc alloys - Chemical analysis - Part 8 : determination of tin in secondary zinc - Flame atomic absorption spectrometric method
NF A06-841-2/A2*NF EN 12441-2/A2:2005 Zinc and zinc alloys - Chemical analysis - Part 2 : determination of magnesium in zinc alloys - Flame atomic absorption spectrometric method
NF A81-365-8*NF EN 29455-8:1993 Solft soldering fluxes. Test methods. Part 8 : determination of zinc content.
NF A08-811:1970 Chemical analysis of zinc. Determination of lead, cadmium, copper and aluminium. (atomic absorption method).
NF A20-604*NF ISO 8753:1987 Iron ores. Determination of lead and/or zinc content. Flame atomic absorption spectrometric method.

British Standards Institution (BSI), how about zinc content

BS EN 12441-5:2003 Zinc and zinc alloys - Chemical analysis - Determination of iron in primary zinc - Spectrophotometric method
BS EN 12441-4:2003 Zinc and zinc alloys - Chemical analysis - Determination of iron in zinc alloys - Spectrophotometric method
BS 3630-16:1976 Methods for the sampling and analysis of zinc and zinc alloys - Nickel in zinc alloys (photometric method)
BS ISO 6101-1:2019 Rubber. Determination of metal content by atomic absorption spectrometry - Determination of zinc content
BS EN 29455-8:1993 Soft soldering fluxes. Test methods. Determination of zinc content
BS ISO 13291:2006 Zinc sulfide concentrates - Determination of zinc - Solvent extraction and EDTA titrimetric method
BS ISO 12739:2006 Zinc sulfide concentrates - Determination of zinc - Ion-exchange/EDTA titrimetric method
BS ISO 13543:2016 Copper, lead, zinc and nickel sulfide concentrates. Determination of mass of contained metal in a lot
18/30359447 DC BS ISO 6101-1. Rubber. Determination of metal content by atomic absorption spectrometry. Part 1. Determination of zinc content
BS EN 12441-6:2003 Zinc and zinc alloys - Chemical analysis - Determination of aluminium and iron - Flame atomic absorption spectrometric method
BS ISO 13310:1997 Iron ores - Determination of zinc content - Flame atomic absorption spectrometric method
BS ISO 12743:2018 Copper, lead, zinc and nickel concentrates. Sampling procedures for determination of metal and moisture content
BS ISO 12743:2007 Copper, lead, zinc and nickel concentrates - Sampling procedures for determination of metal and moisture content

工业和信息化部, how about zinc content

YB/T 4604-2018 Determination of zinc content in crude zinc powder by rotary hearth furnace method EDTA complex titration method
HG/T 5814-2020 Method for determination of zinc content in waste chemicals
YB/T 4726.1-2018 Determination of zinc content in iron-containing dust mud EDTA standard solution titration method
YS/T 1341.1-2019 Methods for chemical analysis of crude zinc Part 1: Determination of zinc content Na2EDTA titration method

(U.S.) Ford Automotive Standards, how about zinc content

FORD FLTM AI 001-01-2000 DETERMINATION OF PERCENT ZINC IN WELDING PRIMERS

NL-NEN, how about zinc content

NEN 3811-1970 Gelatine. Determination of the content of lead, iron, copper and zinc
NEN-ISO 9455-8:1993 Soft soldering fluxes. Test methods. Part 8: Determination of zinc content (ISO 9455-8:1991)

American Society for Testing and Materials (ASTM), how about zinc content

ASTM D1691-02(2007)e1 Standard Test Methods for Zinc in Water
ASTM D1691-90 Standard Test Methods for Zinc in Water
ASTM D1691-95 Standard Test Methods for Zinc in Water
ASTM D1691-02 Standard Test Methods for Zinc in Water
ASTM D6580-17 Standard Test Method for the Determination of Metallic Zinc Content in Both Zinc Dust Pigment and in Cured Films of Zinc-Rich Coatings
ASTM D6580-17(2023) Standard Test Method for The Determination of Metallic Zinc Content in Both Zinc Dust Pigment and in Cured Films of Zinc-Rich Coatings
ASTM A90/A90M-07 Standard Test Method for Weight [Mass] of Coating on Iron and Steel Articles with Zinc or Zinc-Alloy Coatings
ASTM E945-96 Standard Test Method for Determination of Zinc in Zinc Ores and Concentrates by Complexometric Tritrimetry
ASTM E945-02a Standard Test Method for Determination of Zinc in Zinc Ores and Concentrates by Complexometric Tritrimetry
ASTM E945-02 Standard Test Method for Determination of Zinc in Zinc Ores and Concentrates by Complexometric Tritrimetry
ASTM D6580-00(2005) Standard Test Method for the Determination of Metallic Zinc Content in Both Zinc Dust Pigment and in Cured Films of Zinc-Rich Coatings
ASTM D6580-00 Standard Test Method for the Determination of Metallic Zinc Content in Both Zinc Dust Pigment and in Cured Films of Zinc-Rich Coatings
ASTM D6580-00(2009) Standard Test Method for the Determination of Metallic Zinc Content in Both Zinc Dust Pigment and in Cured Films of Zinc-Rich Coatings

German Institute for Standardization, how about zinc content

DIN ISO 1976:1983 Zinc alloys; determination of copper content; electrolytic method
DIN EN 29455-8:1994 Soft soldering fluxes; test methods; part 8: determination of zinc content (ISO 9455-8:1991); German version EN 29455-8:1993
DIN EN 12441-3:2002 Zinc und zinc alloys - Chemical analysis - Part 3: Determination of lead, cadmium and copper; Flame atomic absorption spectrometric method; German version EN 12441-3:2001
DIN 53770-15:1977 Testing of pigments; determination of matter soluble in hydrochloric acid, zinc content

Group Standards of the People's Republic of China, how about zinc content

T/CSTM 01147-2022 Zinc and zinc alloy—Determination of manganese content— Flame atomic absorption spectrometric method
T/CSTM 01143-2022 Zinc and zinc alloys—Determination of bismuth content— Flame atomic absorption spectrometric method
T/CSTM 01146-2022 Zinc and zinc alloys—Determination of indium content— Flame atomic absorption spectrometric method
T/CSTM 01145-2022 Zinc and zinc alloys—Determination of nickel content— Extraction separation-Flame atomic absorption spectrometric method
T/CSTM 01144-2022 Zinc and zinc alloys—Determination of cobalt content—Extraction separation-Flame atomic absorption spectrometric method
T/CSTM 00773-2021 Silver—Determination of zinc content —Flame atomic absorption spectrometric method
T/CSTM 00768-2021 Beryllium and beryllium alloy—Determination of zinc content —Flame atomic absorption spectrometric method

Professional Standard - Chemical Industry, how about zinc content

HG/T 5813～5814-2020 Determination method of lead content and zinc content determination method of waste chemicals (2020)
HG/T 4326-2012 Reclaimed water.Determination of nickel,copper,zinc,cadmium and lead.Atomic absorption spectromic method

Professional Standard - Petrochemical Industry, how about zinc content

SH/T 0226-1992 Determination of zinc content in additives and lubricating oils containing additives
SH/T 0309-1992 Determination method of calcium, barium and zinc content in lubricating oil containing additives (complexometric titration method)
SH/T 0228-1992 Determination of barium, calcium and zinc content in lubricating oil (atomic absorption spectrometry)

European Committee for Standardization (CEN), how about zinc content

EN 12441-4:2003 Zinc and zinc alloys - Chemical analysis - Part 4: Determination of iron in zinc alloys; Spectrophotometric method

Professional Standard - Commodity Inspection, how about zinc content

SN/T 3604-2013 Determination of copper, silicon, manganese, zinc, aluminum and iron in zinc concentrate ore.X-ray fluorescence spectrometry
SN/T 1732.3-2014 Pyrotechnic composition used for fireworks and firecracker.Part 3:Determination of zincum content
SN/T 1732.3-2006 Pyrotechnic composition used for fireworks and firecracker--Part 3: Determination of zincum content

Standard Association of Australia （SAA）, how about zinc content

AS 1329.1:1994 Methods for the analysis of zinc and zinc alloys - Determination of aluminium content - Titrimetric method
AS 2678.2:2008 Zinc sulfide concentrates - Chemical analysis - Determination of zinc - Ion-exchange/EDTA titrimetric method
AS 2678.1:2008 Zinc sulfide concentrates - Chemical analysis - Determination of zinc - Solvent extraction and EDTA titrimetric method
AS 1580.504.1:2005 Paints and related materials - Methods of test - Metallic zinc content
AS 1329.3:1994 Methods for the analysis of zinc and zinc alloys - Determination of aluminium content - Flame atomic absorption spectrometric method
AS 1329.7:1994 Methods for the analysis of zinc and zinc alloys - Determination of lead content - Flame atomic absorption spectrometric method
AS 1329.8:1994 Methods for the analysis of zinc and zinc alloys - Determination of cadmium content - Flame atomic absorption spectrometric method
AS 1329.6:1994 Methods for the analysis of zinc and zinc alloys - Determination of copper content (0.25% to 1.25%) - Flame atomic absorption spectrometric method
AS 1329.5:1994 Methods for the analysis of zinc and zinc alloys - Determination of copper content (0.0001% to 0.0025%) - Flame atomic absorption spectrometric method
AS 1329.2:1994 Methods for the analysis of zinc and zinc alloys - Determination of magnesium content - Flame atomic absorption spectrometric method

Professional Standard - Ferrous Metallurgy, how about zinc content

YB/T 4217.1-2010 Determination of hexavalent chromium content in coatings of hot-dip galvanized (aluminum-zinc) steel sheets Spectrophotometric method
YB/T 4217.2-2010 Determination of mercury content in coatings of hot-dip galvanized (aluminum-zinc) steel sheets Cold mercury vapor atomic absorption spectrometry
YB/T 4217.3-2010 Determination of lead and cadmium content in coatings of hot-dip galvanized (aluminum-zinc) steel sheets by inductively coupled plasma emission spectrometry

中华人民共和国国家质量监督检验检疫总局、中国国家标准化管理委员会, how about zinc content

GB/T 5195.7-2016 Fluorspar—Determination of zinc content—Flame atomic absorption spectrophotometric method

Yunnan Provincial Standard of the People's Republic of China, how about zinc content

DB53/T 729-2015 Determination of germanium content in zinc materials spectrophotometric method
DB53/T 728-2015 Determination of Indium Content in Zinc Materials - Atomic Absorption Spectrophotometry
DB53/T 918-2019 Determination of sulfuric acid content in ferric zinc sulfate solution by acid-base titration

ES-UNE, how about zinc content

UNE 37254:1987 ERRATUM LEAD. DETERMINATION OF ZINC CONTENT. SPECTROMETRIC METHOD ABSORPTION TECHNIQUE.

国家市场监督管理总局、中国国家标准化管理委员会, how about zinc content

GB 24427-2021 Content limitation of mercury, cadmium and lead for zinc anode primary battery
GB/T 40342-2021 Method for determination of aluminum content in hot dipped zinc-aluminum alloy coating on steel wire
GB/T 38233-2019 Iron-bearing dust and sludge- Determination of lead and zinc content- Inductively coupled plasma atomic emission spectrometry
GB/T 8151.24-2021 Methods for chemical analysis of zinc concentrates—Part 24：Determination of soluble zinc content—Flame atomic absorption spectrometry
GB/T 14949.6-2021 Manganese ores—Determination of copper, lead and zinc content—Flame atomic absorption spectrometric method
GB/T 20975.8-2020 Methods for chemical analysis of aluminium and aluminium alloys—Part 8：Determination of zinc content

Malaysia Standards, how about zinc content

MS 1449 Pt.1-1999

KR-KS, how about zinc content

KS E ISO 13543-2020 Copper, lead, zinc and nickel sulfide concentrates —Determination of mass of contained metal in a lot
KS B ISO 9455-8-2019 Soft soldering fluxes — Test methods — Part 8: Determination of zinc content
KS E ISO 9599-2018 Copper, lead, zinc and nickel sulfide concentrates — Determination of hygroscopic moisture content of the analysis sample — Gravimetric method

IT-UNI, how about zinc content

AR-IRAM, how about zinc content

IRAM 665-1956

ES-AENOR, how about zinc content

Tianjin Provincial Standard of the People's Republic of China, how about zinc content

DB12/T 954-2020 Spectrophotometric method for determination of copper and zinc content in manure from dairy farms

Taiwan Provincial Standard of the People's Republic of China, how about zinc content

CNS 10096-1983 Method of Test for Zinc in Lubricating Oils and Additives (Polarographic Method)

Danish Standards Foundation, how about zinc content

DS/ISO 9455-8:1994 Soft soldering fluxes - Test methods - Part 8: Determination of zinc content
DS/ISO 6101/1:1984 Rubber. Determination of metal content. Flame atomic absorption spectrometric method. Part 1: Determination of zinc content
DS/EN 29455-8:1994 Soft soldering fluxes. Test methods. Part 8: Determination of zinc content

Professional Standard - Aviation, how about zinc content

HB 6731.3-1993 Determination of Zinc Content in Aluminum Alloys by Atomic Absorption Spectrometry
HB 5422.18-1989 Copper alloy chemical analysis method MIBK extraction and separation—EDTA volumetric method for determination of zinc content
HB/Z 5084.1-2000 Analytical method of cyanide electroplating zinc solution complexometric titration for continuous determination of sodium cyanide and zinc oxide
HB 5219.12-1998 Determination of Zinc Content by Trin-Octylamine Extraction-EDTA Volumetric Method for Magnesium Alloy Chemical Analysis

未注明发布机构, how about zinc content

BS ISO 13310:1997(1999) Iron ores — Determination of zinc content — Flame atomic absorption spectrometric method

Sichuan Provincial Standard of the People's Republic of China, how about zinc content

DB51/T 2443-2018 Determination of mulberry silk content in mulberry/tussah products by formic acid/zinc chloride method

SE-SIS, how about zinc content

SIS SS 02 81 01-1992 Nitrogen content of water — Determination with Kjeldahl method after reduction with Devarda's alloy