liquid level

liquid level, Total:239 items.

The international standard classification for "liquid level" includes: Measurement of volume, mass, density, viscosity , Thermodynamics and temperature measurements , Filters, seals and contamination of fluids , Protection against dangerous goods , Products of the chemical industry in general , Petroleum products in general , Geology. Meteorology. Hydrology , Inks. Printing inks , Temperature-measuring instruments , Volumetric equipment and measurements , Fuels , Aerospace engines and propulsion systems , Fertilizers .

The Chinese standard classification for "liquid level" includes: Mechanics Measurement , Thermal Measurement , Hydraulic and pneumatic device , Marking, packaging, transport and storage in general , Basic standards and general methods for dye , Petroleum products in general , Meteorological instrument , Other daily-use chemicals , Printing Technology , Basic standards and general methods , Fire-fighting in general , Spacecraft power system , Soil and fertilizer in general .

National Metrological Verification Regulations of the People's Republic of China

JJG 130-2011 Verification Regulation of Liquid-in-Glass Thermometers for working
JJG 1061-2010 Liquid-borne Particle Counters
JJG 130-2004 Liquid-in-Glass Thermometers for Working
JJG 130-1984 Verification Regulation of Liquid-in-Glass Thermometers for Working
JJG 1058-2010 Laboratory Oscillation-type Liquid Density meters
JJG 50-1996 Liquid -in -Glass Thermometers for Petroleum Products
JJG 207-1992 Verification Regulation of Meteorological Hair Hygrometer
JJG 171-2016 Ralative Density Balance for Liquid
JJG 370-2019 On-line Oscillation Tube Liquid Density Meters
JJG 999-2018 Digital Weighted-Method Liquid Density Meters
JJG(石油) 15-1994 Verification Regulation of Density Meters of Drilling Fluids
JJG 370-1984 Working Vibration Tube Liquid Density Meter
JJG 171-1985 Verification Regulation of Hydrometric Balance
JJG 171-2004 Verification Regulation of Ralative Density Balance for Liquid
JJG 370-2007 Verification Regulation for Vibration Tube Liquid Density Meter on Line
JJG 999-2005 Verification Regulation of Digital Liquid Density Meter-Weighed Method

General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China

GB/T 22235-2008 Determination for viscosity of liquids
GB/T 27613-2011 Hydraulic fluid power—Fluid contamination—Determination of particulate contamination by the gravimetric method
GB/T 21882-2008 Liquid dyes - Determination of the viscosity
GB/T 5332-2007 Method of test for ignition temperature of flammable liquids and gases
GB/T 5332-1985 Method of test for ignition temperature of flammable liquids and gases
GB/T 13217.4-2008 Test method for viscosity of liquid ink
GB 5332-1985 Method of test for ignition temperature of flammable liquids and gases
GB/T 13217.3-2008 Test method for fineness of grind of liquid ink
GB/T 8747-1988 Meteorological liquid-in-glass thermometer
GB 8023-1987 Liquid petroleum products; Viscosity; Temperature charts
GB/T 8023-1987 Liquid petroleum products--Viscosity--Temperature charts
GB/T 8747-2010 Meteorological liquid-in-glass thermometer
GB/T 8927-2008 Petroleum and liquid petroleum products—Temperature measurment—Manual methods

Jilin Provincial Standard of the People's Republic of China

DB22/T 2876-2018 Technical regulations for the production of black fungus liquid strains

Professional Standard - Aerospace

QJ 1003-1986 Liquid rocket engine design program
QJ 1003A-2004 Design procedure for liquid propellant rocket engine
QJ 2485-1993 Cryogenic liquid (liquid hydrogen, liquid oxygen) density measurement specification
QJ 1043-1986 Ground Test Run Procedure of Liquid Rocket

Guangxi Provincial Standard of the People's Republic of China

DB45/T 958-2013 Technical regulations for biogas liquid fertilizer application for vegetable planting
DB45/T 957-2013 Technical regulations for the application of rice planting biogas slurry and biogas liquid fertilizer
DB45/T 956-2013 Biogas slurry biological liquid fertilizer production technical regulations

Professional Standard - Agriculture

NY/T 887-2004 Density testing of liquid fertilizer
NY/T 887-2010 Liquid fertilizers--Determination of density

Professional Standard - Energy

NB/SH/T 0874-2013 Density Determination of Crude Oil and Liquefied Petrolatum Products in Laboratory - Weighing Digital Display Liquid Densimeter Method

Group Standards of the People's Republic of China

T/YFSEA 0008-2023 Inspection regulations for land-based liquid loading and unloading arms
T/ZZB 1518-2020 Liquid expansion pressure thermometer

国家能源局

NB/T 10095-2018 Liquid expansion pressure thermometer

国家市场监督管理总局、中国国家标准化管理委员会

GB/T 37162.1-2018 Hydraulic fluid power—Monitoring the level of particulate contamination of the fluid—Part 1:General principles

Professional Standard - Coal

MT/T 549-1996 Maintenance Instructions of Single Hydraulic Prop

Taiwan Provincial Standard of the People's Republic of China

CNS 11027-1984 Definitions of Terms Relating to Density and Specific Gravity of Solids Liquids and Gases
CNS 3163-1971 Liquid detergent (for printing and dyeing processes)

Professional Standard - Aviation

HB 5930-1986 Classification of Solid Pollution Degree of Working Fluid in Aircraft Hydraulic System

Military Standard of the People's Republic of China-General Armament Department

GJB 420A-1996 Classification of solid contamination of oil used in aircraft hydraulic systems
GJB 420-1987 Classification of solid contamination of oil used in aircraft hydraulic systems

Professional Standard - Chemical Industry

HG/T 21608-2012 Engineering Technical Requirements for Liquid Loading Arm

承德市市场监督管理局

DB1308/T 316-2022 Technical regulations for the production of solid-to-liquid strains of shiitake mushrooms

Military Standard of the People's Republic of China-Commission of Science,Technology and Industry for National Defence

GJB 420B-2006 Solid particle contamination classes for fluid of aviation

American Society for Testing and Materials (ASTM)

ASTM D6080-12 Standard Practice for Defining the Viscosity Characteristics of Hydraulic Fluids
ASTM D6080-10 Standard Practice for Defining the Viscosity Characteristics of Hydraulic Fluids
ASTM D6080-18a Standard Practice for Defining the Viscosity Characteristics of Hydraulic Fluids
ASTM D6080-18 Standard Practice for Defining the Viscosity Characteristics of Hydraulic Fluids
ASTM D6080-97 Standard Practice for Defining the Viscosity Characteristics of Hydraulic Fluids
ASTM D4904-99(2004) Standard Practice for Preparation of Solution of Liquid Vegetable Tannin Extracts
ASTM D4904-99 Standard Practice for Cooling of Analytical Solutions
ASTM E2251-14 Standard Specification for Liquid-in-Glass ASTM Thermometers with Low-Hazard Precision Liquids
ASTM E2251-07 Standard Specification for Liquid-in-Glass ASTM Thermometers with Low-Hazard Precision Liquids
ASTM D6759-24 Standard Practice for Sampling Liquids Using Grab and Discrete Depth Samplers
ASTM D8210-19a Standard Test Method for Automatic Determination of Low-Temperature Viscosity of Automatic Transmission Fluids, Hydraulic Fluids, and Lubricants Using a Rotational Viscometer
ASTM D8210-22 Standard Test Method for Automatic Determination of Low-Temperature Viscosity of Automatic Transmission Fluids, Hydraulic Fluids, and Lubricants Using a Rotational Viscometer
ASTM D8210-20 Standard Test Method for Automatic Determination of Low-Temperature Viscosity of Automatic Transmission Fluids, Hydraulic Fluids, and Lubricants Using a Rotational Viscometer
ASTM D8210-19 Standard Test Method for Automatic Determination of Low-Temperature Viscosity of Automatic Transmission Fluids, Hydraulic Fluids, and Lubricants Using a Rotational Viscometer
ASTM D8210-19b Standard Test Method for Automatic Determination of Low-Temperature Viscosity of Automatic Transmission Fluids, Hydraulic Fluids, and Lubricants Using a Rotational Viscometer
ASTM D8210-18 Standard Test Method for Automatic Determination of Low-Temperature Viscosity of Automatic Transmission Fluids, Hydraulic Fluids, and Lubricants Using a Rotational Viscometer
ASTM E2251-10 Standard Specification for Liquid-in-Glass ASTM Thermometers with Low-Hazard Precision Liquids
ASTM G73-04 Standard Practice for Liquid Impingement Erosion Testing
ASTM E2251-14(2021) Standard Specification for Liquid-in-Glass ASTM Thermometers with Low-Hazard Precision Liquids
ASTM F862-11 Standard Practice for pH and Chloride-ion Concentration of Aerospace Hydraulic Fluids
ASTM E1-14(2020) Standard Specification for ASTM Liquid-in-Glass Thermometers

GSO

GSO ISO 4406:2023 Hydraulic fluid power — Fluids — Method for coding the level of contamination by solid particles
BH GSO ISO 4406:2023 Hydraulic Fluid Power — Fluids — Method for Coding the Level of Contamination by Solid Particles
OS GSO OIML R133:2008 Liquid-in-Glass Thermometers
OS GSO ISO 15212-2:2010 Oscillation-type density meters -- Part 2: Process instruments for homogeneous liquids
GSO ISO 15212-2:2010 Oscillation-type density meters -- Part 2: Process instruments for homogeneous liquids
GSO ISO 16431:2015 Hydraulic fluid power -- System clean-up procedures and verification of cleanliness of assembled systems
OS GSO 1208:2002 Determination of density and relative density of liquids by digtal density meter .

SCC

DANSK DS/ISO 4406:2021 Hydraulic fluid power – Fluids – Method for coding the level of contamination by solid particles
NS 5911:1988 Hydraulic fluid power — Fluids — Method for coding level of contamination by solid particles (ISO 4406:1987 modified)
DANSK DS/EN ISO 15212-2/AC:2009 Oscillation-type density meters - Part 2: Process instruments for homogenous liquids
DANSK DS/EN ISO 15212-2:2002 Oscillation-type density meters - Part 2: Process instruments for homogenous liquids
DANSK DS/EN 16603-35-03:2014 Space engineering - Liquid propulsion for launchers
BS 188:1937 Determination of the viscosity of liquids in c.g.s. units
BS 188:1970 Determination of the viscosity of liquids in c.g.s. units

Danish Standards Foundation

DS/ISO 4406:2021 Hydraulic fluid power – Fluids – Method for coding the level of contamination by solid particles
DS/EN ISO 15212-2/AC:2009 Oscillation-type density meters - Part 2: Process instruments for homogenous liquids
DS/EN ISO 15212-2:2002 Oscillation-type density meters - Part 2: Process instruments for homogenous liquids

NO-SN

NS 5911-1988 Hydraulic fluid power - Fluids - Method for coding level of contamination by solid particles

Korean Agency for Technology and Standards (KATS)

KS B 5213-2003 Specific gravity hydrometers
KS B 5302-1983 Etched-stem liquid-in glass thermometer
KS A 0531-2011 Viscosity of liquid-Methods of measurement
KS B ISO 15212-2-2021 Oscillation-type density meters－Part 2：Process instruments for homogeneous liquids
KS A 0531-2016(2021) Viscosity of liquid－Methods of measurement
KS A 0531-2021 Viscosity of liquid－Methods of measurement
KS M 1071-10-2018 Guide for determination of the viscosity of liquids of chemical substances
KS A 0531-2016 Viscosity of liquid－Methods of measurement
KS B 5218-1983 Etched-Stem liquid-in-glass wet & dry thermometer
KS B ISO 15212-2:2006 Oscillation-type density meters－Part 2：Process instruments for homogeneous liquids
KS B 5217-1990 Bimetallic thermometers for atmospheric temperature
KS A 0512-2019 Method of temperature measurement by liquid-in-glass thermometers
KS A 0512-2009(2019) Method of temperature measurement by liquid-in-glass thermometers
KS B 5302-2021 Etched-stem liquid-in glass thermometer
KS A 0512-1994 Method of temperature measurement by liquid-in-glass thermometers
KS M 2002-1986 Crude petroleum and liquid petroleum products-Laboratory determination of density-Hydrometer method
KS M 2002-2011 Crude petroleum and liquid petroleum products-Laboratory determination of density-Hydrometer method
KS A 5103-2023 Standard liquids for calibrating viscometers
KS M 1071-10-2007 Guide for determination of the viscosity of liquids of chemical substances

HU-MSZT

MSZ 9790-1985 Fire hazard classification of flammable liquids and solvents
MSZ 11237-1967 Glass Thermometer Liquid Fill Thermometer
MSZ 9904-1976 Storage and transportation of highly flammable liquids 300 liters
MSZ KGST 1504-1979 Density determination of liquid mixtures

ESDU - Engineering Sciences Data Unit

ESDU 65008-1965 Viscosity of liquid benzene.
ESDU 95020-1995 Viscosity of liquids: Carboxylic acids.
ESDU 97027 A-2006 Viscosity of liquids: Aliphatic amines.
ESDU 97027-1997 Viscosity of liquids Aliphatic amines
ESDU 02001-2002 Viscosity of liquids: Aliphatic nitriles
ESDU 02001 A-2006 Viscosity of liquids: Aliphatic nitriles.
ESDU 99022-2000 Viscosity of liquids: Halogenated aromatic hydrocarbons.
ESDU 95019 A-2006 Viscosity of liquids: Aliphatic ethers.
ESDU 95019-1995 Viscosity of liquids Aliphatic ethers
ESDU 93012-1993 Viscosity of liquids: Halogenated ethanes.
ESDU 06007-2006 Viscosity of liquids: Glycol ethers.
ESDU 92028-1992 Viscosity of liquids: Halogenated methanes.
ESDU 06008-2006 Viscosity of liquids: Branched chain aliphatic esters.
ESDU 71003-1971 A guide to the viscosity of liquid petroleum products.
ESDU 96020-1996 Viscosity of liquids Straight chain aliphatic esters
ESDU 96020 A-2006 Viscosity of liquids: Straight chain aliphatic esters.
ESDU 76021-1976 Dynamic viscosity of carbon dioxide gas and liquid.
ESDU 89037-1989 Orthobaric densities and molar volumes of liquids. Alcohols.
ESDU 89019 A-1990 Orthobaric densities and molar volumes of liquids. Aromatic hydrocarbons.
ESDU 94025-1994 Viscosity of liquids Aliphatic and cyclic ketones
ESDU 98015-1998 Orthobaric densities and molar volumes of liquids. Halogenated benzenes.
ESDU 91034-1991 Orthobaric densities and molar volumes of liquids. Halogenated methanes.
ESDU 92018-1992 Orthobaric densities and molar volumes of liquids. Halogenated ethylenes.
ESDU 92009 A-2003 Orthobaric densities and molar volumes of liquids: Halogenated ethanes.
ESDU 94025 A-2006 Viscosity of liquids: Aliphatic and cyclic ketones.
ESDU 03007-2003 Viscosity of liquids: Aromatic compounds containing oxygen

United States Navy

NAVY MIL-F-24259 A-1987 FLUID FLOWMETER, VOLUME VELOCITY TYPE

CZ-CSN

CSN ON 13 4975-1967 Remote liquid water mark
CSN 56 0161-6-1996 Methods for testing of liquid sugars. Determination of turbidity.
CSN 65 0342-1980 Liquid chemical products. Method for the determination of density
CSN 25 7616-1986 Glass areometers of constant mass. Milk density hydrometers. Dimensions

International Organization for Standardization (ISO)

ISO/CD TR 6037 Automated liquid handling systems – Uncertainty of the measurement procedures
ISO 15212-2:2002 Oscillation-type density meters - Part 2: Process instruments for homogeneous liquids
ISO 748:2021 Hydrometry — Measurement of liquid flow in open channels — Velocity area methods using point velocity measurements
ISO/TR 10686:2013 Hydraulic fluid power - Method to relate the cleanliness of a hydraulic system to the cleanliness of the components and hydraulic fluid that make up the system
ISO 4630:2015 Clear liquids - Estimation of colour by the Gardner colour scale

RU-GOST R

GOST 17216-2001 Industrial cleanliness. Grades of liquids purity
GOST 31247-2004 Industrial cleanliness. Determination of fluid sample contamination using automatic particle counter
GOST R 8.701-2010 State system for ensuring the uniformity of measuremenets. Liquid purity measuring instruments. Verification procedure
GOST ISO/TR 10949-2007 Industrial cleanliness. Guidelines for provision and controlling cleanliness of hydraulic fluid power components from manufacture to installation
GOST ISO/TS 16431-2007 Industrial cleanliness. Verification of hydraulic fluid power systems cleanliness

German Institute for Standardization

DIN EN ISO 15212-2:2002-07 Oscillation-type density meters - Part 2: Process instruments for homogeneous liquids (ISO 15212-2:2002); German version EN ISO 15212-2:2002
DIN EN ISO 15212-2 Berichtigung 1:2009-07 Oscillation-type density meters - Part 2: Process instruments for homogeneous liquids (ISO 15212-2:2002); German version EN ISO 15212-2:2002, Corrigendum to DIN EN ISO 15212-2:2002-07; German version EN ISO 15212-2:2002/AC:2009
DIN 53017:1993 Viscometry; determination of the temperature coefficient of viscosity of liquids
DIN 51398:1983 Testing of lubricants; procedure for measurement of low temperature apparent viscosity by means of the Brookfield viscometer (liquid bath method)
DIN 12769:1980 Liquid-in-glass thermometers; survey
DIN 53017:1993-11 Viscometry; determination of the temperature coefficient of viscosity of liquids
DIN EN 12162:2001 Liquid pumps - Safety requirements - Procedure for hydrostatic testing
DIN 1342-2:1986 Viscosity - Part 2: Newtonian liquids
DIN 1342-2 E:1999-12 Viscosity - Part 2: Newtonian liquids
DIN 1342-2:2003-11 Viscosity - Part 2: Newtonian liquids
DIN 1342-3:2003-11 Viscosity - Part 3: Non-newtonian liquids
DIN 1342-3 E:1999-12 Viscosity - Part 3: Non-newtonian liquids
DIN 1342-3:2003 Viscosity - Part 3: Non-newtonian liquids
DIN EN ISO 3675:1999-11 Crude petroleum and liquid petroleum products - Laboratory determination of density - Hydrometer method (ISO 3675:1998); German version EN ISO 3675:1998
DIN EN ISO 20361 E:2015-08 Noise test procedures for liquid pumps and pump units. Level 2 and 3 accuracy (draft)
DIN EN ISO 20361 E:2018-09 Noise test procedures for liquid pumps and pump units. Level 2 and 3 accuracy (draft)
DIN EN 16603-35-03:2014-12 Space engineering - Liquid propulsion for launchers; English version EN 16603-35-03:2014

Spanish Association for Standardization (UNE)

UNE-EN ISO 15212-2:2002/AC:2010 Oscillation-type density meters - Part 2: Process instruments for homogeneous liquids (ISO 15212-2:2002/Cor 1:2008)
UNE-EN ISO 15212-2:2003 Osscilation-type density meters. Part 2: Process instruments for homogenous liquids. (ISO 15212-2:2002)
UNE-EN 16603-35-03:2014 Space engineering - Liquid propulsion for launchers (Endorsed by AENOR in November of 2014.)
UNE 51601:1981 INDUSTRIAL LIQUID LUBRICANTS. UNE VISCOSITY CLASSIFICATION

British Standards Institution (BSI)

BS EN ISO 15212-2:2002(2009) Oscillation - typedensity meters — Part 2 : Process instruments for homogenous liquids
BS ISO 14952-5:2004 Space systems - Surface cleanliness of fluid systems - Drying processes
BS 188:1976 Methods for determination of the viscosity of liquids
BS 188:1977 Methods for determination of the viscosity of liquids
BS ISO 21018-4:2019 Hydraulic fluid power. Monitoring the level of particulate contamination in the fluid. Use of the light extinction technique
BS ISO 14952-6:2004 Space systems - Surface cleanliness of fluid systems - Precision-cleaning processes
BS ISO 14952-4:2004 Space systems - Surface cleanliness of fluid systems - Rough-cleaning processes
BS 188:1977(2012) Methods for Determination of the viscosity of liquids
BS EN ISO 20783-2:2004 Petroleum and related products - Determination of emulsion stability of fire-resistant fluids - Fluids in category HFB
BS EN ISO 15212-2:2002 Oscillation-type density meters — Part 2: Process instruments for homogenous liquids
BS ISO 16431:2012 Hydraulic fluid power. System Cleanup-procedures and verification of cleanliness of assembled systems
BS EN 12162:2001 Liquid pumps - Safety requirements - Procedure for hydrostatic testing
BS EN ISO 4630:2015 Clear liquids. Estimation of colour by the Gardner colour scale

GOST

GOST 17216-1971 Industries purity. Grades of liquids purity

FI-SFS

SFS 3772-1976 Determination of liquid density at 20 degrees Celsius
SFS 3846-1979 plastic. Liquid, emulsion polymer or dispersion polymer. Determining viscosity with a rotational viscometer

ES-AENOR

INTA 15 03 04 Alkalinity of volatile liquids

Japanese Industrial Standards Committee (JISC)

JIS Z 8803:2011 Methods for viscosity measurement of liquid
JIS Z 8803:1991 Viscosity of liquid -- Methods of measurement
JIS B 7525-3:2013 Hydrometer-type relative density meters
JIS Z 8705:1992 Method of temperature measurement by liquid-in-glass thermometers

National Aeronautics and Space Administration (NASA)

NASA-TN-D-6453-1971 FORTRAN programs for the design of liquid-to-liquid jet pumps

IN-BIS

IS 4730-1968 How to measure the density of liquids
IS 4825-1982 Specification for liquid glass solid stem reference thermometers
IS 3658-1981 Liquid Penetrant Inspection Operating Procedures
IS 9466-1980 Viscosity classification of industrial liquid lubricants
IS 6274-1971 How to Calibrate a Liquid in Glass Thermometer

Military Standards (MIL-STD)

DOD A-A-51344 B-1992 GRADUATE, LIQUID, LABORATORY
DOD A-A-53608-1988 HYDROMETERS, GRADUATED SCALE (WITH THERMOMETER, API GRAVITY)
DOD A-A-54076-1990 HYDROMETER, GRADUATED SCALE API GRAVITY
DOD A-A-51059-1985 GRADUATE, LIQUID, LABORATORY, (CORROSION RESISTING)

SE-SIS

SIS 02 14 11-1966 Determination of density by hydrometer

American National Standards Institute （ANSI)

ANSI/NFPA 30-2003 Flammable and Combustible Liquids Code
ANSI/NFPA 55-2012 Compressed Gases and Cryogenic Fluids Code

GOSTR

GOST 34560-2019 Hydraulic fluid power. Evaluation and verification procedures of cleanliness of assembled systems

European Committee for Standardization (CEN)

EN ISO 15212-2:2002 Oscillation-type density meters - Part 2: Process instruments for homogenous liquids (ISO 15212-2:2002)

KR-KS

KS B ISO 20361-2008 Liquid pumps and pump units－Noise test code－Grades 2 and 3 of accuracy
KS A 5103-1993(2023) Standard liquids for calibrating viscometers
KS A 0512-2009(2024) Method of temperature measurement by liquid-in-glass thermometers

ASHRAE - American Society of Heating@ Refrigerating and Air-Conditioning Engineers@ Inc.

ASHRAE 3694-1993 Demonstration of a High- Temperature Heat Pump for Minimizing Liquid Indutrial Waste
ASHRAE DA-07-011-2007 Liquid Cooling for Extreme Heat Densities

RO-ASRO

STAS R 9661-1974 HydrauFc drives SPEEDS OF WORKING LIQUID IN PIPES
STAS 1081-1980 LIQUID SOLUTIONS CONCENTRATION Glossary of terms and units of measure

Natural Gas Processor's Association (NGPA)

GPA RR-147-1995 Density Measurements on Natural Gas Liquids
GPA TP-2-1972 Liquid Densities of High-Ethane Raw Make Streams
GPA RR-62-1982 Water-Hydrocarbon Liquid-Liquid-Vapor Equilibrium Measurements to 530 Degrees F
GPA TP-12-1985 Liquid Densities of Ethane - Propane Mixtures

Association Francaise de Normalisation

NF EN ISO 2555:2018 Plastics - Resins in liquid state or in emulsions or dispersions - Determination of apparent viscosity by the single-cylinder rotary viscometer method
FD X07-029-3:2015 Metrology - Thermometer calibration and verification procedure - Part 3 : calibration and verification procedure for liquid in glass thermometers
NF E44-420:2009 Liquid pumps and pump units - Noise test code - Grades 2 and 3 of accuracy.
NF EN 16603-35-03:2016 Ingénierie spatiale - Propulsion liquide pour lanceurs
NF EN ISO 3675:1998 Crude oil and liquid petroleum products - Laboratory determination of density - Hydrometer method