ASTM D4057 standard practice for manual sampling of petroleum and petroleum products
1. Scope
1.1 This practice covers procedures and equipment for manually obtaining samples of liquid petroleum and petroleum products, crude oils, and intermediate products from the sample point into the primary container are described. Procedures are also included for the sampling of free water and other heavy components associated with petroleum and petroleum products.

1.2 This practice also addresses the sampling of semi-liquid or solid-state petroleum products.

1.3 This practice provides additional specific information about sample container selection, preparation, and sample handling.

1.4 This practice does not cover sampling of electrical insulating oils and hydraulic fluids. If sampling is for the precise determination of volatility, use Practice D5842 (API MPMS Chapter 8.4) in conjunction with this practice. For sample mixing and handling, refer to Practice D5854 (API MPMS Chapter 8.3).

1.5 The procedures described in this practice may also be applicable in sampling most non-corrosive liquid industrial chemicals provided that all safety precautions specific to these chemicals are followed. Also, refer to Practice E300. The procedures described in this practice are also applicable to sampling liquefied petroleum gases and chemicals. Also refer to Practices D1265 and D3700. The procedure for sampling bituminous materials is described in Practice D140. Practice D4306 provides guidance on sample containers and preparation for sampling aviation fuel.

1.6 Units - The values stated in SI units are to be regarded as the standard. USC units are reflected in parentheses.

1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

2. Referenced Documents
2.1 ASTM Standards:
D86 Test Method for Distillation of Petroleum Products at Atmospheric Pressure
D97 Test Method for Pour Point of Petroleum Products
D140 Practice for Sampling Bituminous Materials
D217 Test Methods for Cone Penetration of Lubricating Grease
D244 Test Methods and Practices for Emulsified Asphalts
D268 Guide for Sampling and Testing Volatile Solvents and Chemical Intermediates for Use in Paint and Related Coatings and Material
D287 Test Method for API Gravity of Crude Petroleum and Petroleum Products (Hydrometer Method)
D323 Test Method for Vapor Pressure of Petroleum Products (Reid Method)
D346 Practice for Collection and Preparation of Coke Samples for Laboratory Analysis
D445 Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)
D473 Test Method for Sediment in Crude Oils and Fuel Oils by the Extraction Method (API MPMS Chapter 10.1)
D664 Test Method for Acid Number of Petroleum Products by Potentiometric Titration
D977 Specification for Emulsified Asphalt
D1265 Practice for Sampling Liquefied Petroleum (LP) Gases, Manual Method
D1267 Test Method for Gage Vapor Pressure of Liquefied Petroleum (LP) Gases (LP-Gas Method)
D1298 Test Method for Density, Relative Density, or API Gravity of Crude Petroleum and Liquid Petroleum Products by Hydrometer Method (API MPMS Chapter 9.1)
D1657 Test Method for Density or Relative Density of Light Hydrocarbons by Pressure Hydrometer (API MPMS Chapter 9.2)
D1838 Test Method for Copper Strip Corrosion by Liquefied Petroleum (LP) Gases
D1856 Test Method for Recovery of Asphalt From Solution by Abson Method
D2172 Test Methods for Quantitative Extraction of Bitumen From Bituminous Paving Mixtures
D2622 Test Method for Sulfur in Petroleum Products by Wavelength Dispersive X-ray Fluorescence Spectrometry
D3230 Test Method for Salts in Crude Oil (Electrometric Method)
D3700 Practice for Obtaining LPG Samples Using a Floating Piston Cylinder
D4006 Test Method for Water in Crude Oil by Distillation (API MPMS Chapter 10.2)
D4007 Test Method for Water and Sediment in Crude Oil by the Centrifuge Method (Laboratory Procedure) (API MPMS Chapter 10.3)
D4177 Practice for Automatic Sampling of Petroleum and Petroleum Products (API MPMS Chapter 8.2)
D4294 Test Method for Sulfur in Petroleum and Petroleum Products by Energy Dispersive X-ray Fluorescence Spectrometry
D4306 Practice for Aviation Fuel Sample Containers for Tests Affected by Trace Contamination
D4377 Test Method for Water in Crude Oils by Potentiometric Karl Fischer Titration (API MPMS Chapter 10.7)
D4530 Test Method for Determination of Carbon Residue (Micro Method)
D4629 Test Method for Trace Nitrogen in Liquid Petroleum Hydrocarbons by Syringe/Inlet Oxidative Combustion and Chemiluminescence Detection
D4807 Test Method for Sediment in Crude Oil by Membrane Filtration (API MPMS Chapter 10.8)
D4840 Guide for Sample Chain-of-Custody Procedures
D4928 Test Method for Water in Crude Oils by Coulometric Karl Fischer Titration (API MPMS Chapter 10.9)
D4929 Test Methods for Determination of Organic Chloride Content in Crude Oil
D5002 Test Method for Density and Relative Density of Crude Oils by Digital Density Analyzer
D5191 Test Method for Vapor Pressure of Petroleum Products (Mini Method)
D5762 Test Method for Nitrogen in Petroleum and Petroleum Products by Boat-Inlet Chemiluminescence
D5842 Practice for Sampling and Handling of Fuels for Volatility Measurement (API MPMS Chapter 8.4)
D5853 Test Method for Pour Point of Crude Oils
D5854 Practice for Mixing and Handling of Liquid Samples of Petroleum and Petroleum Products (API MPMS Chapter 8.3)
D5863 Test Methods for Determination of Nickel, Vanadium, Iron, and Sodium in Crude Oils and Residual Fuels by Flame Atomic Absorption Spectrometry
D6299 Practice for Applying Statistical Quality Assurance and Control Charting Techniques to Evaluate Analytical Measurement System Performance
D6377 Test Method for Determination of Vapor Pressure of Crude Oil: VPCRx (Expansion Method)
D6470 Test Method for Salt in Crude Oils (Potentiometric Method)
D6560 Test Method for Determination of Asphaltenes (Heptane Insolubles) in Crude Petroleum and Petroleum Products
D6822 Test Method for Density, Relative Density, and API Gravity of Crude Petroleum and Liquid Petroleum Products by Thermohydrometer Method (API MPMS Chapter 9.3)
D6849 Practice for Storage and Use of Liquefied Petroleum Gases (LPG) in Sample Cylinders for LPG Test Methods
D7169 Test Method for Boiling Point Distribution of Samples with Residues Such as Crude Oils and Atmospheric and Vacuum Residues by High Temperature Gas Chromatography
E300 Practice for Sampling Industrial Chemicals
E882 Guide for Accountability and Quality Control in the Chemical Analysis Laboratory

2.2 API Manual of Petroleum Measurement Standards:
MPMS Chapter 8.2 Automatic Sampling of Petroleum and Petroleum Products (ASTM Practice D4177)
MPMS Chapter 8.3 Standard Practice for Mixing and Handling of Liquid Samples of Petroleum and Petroleum Products (ASTM Practice D5854)
MPMS Chapter 8.4 Standard Practice for the Sampling and Handling of Fuels for Volatility Measurements (ASTM Practice D5842)
MPMS Chapter 9.1 Standard Test Method for Density, Relative Density (Specific Gravity), or API Gravity of Crude Petroleum and Liquid Petroleum (ASTM Test Method D1298)
MPMS Chapter 9.2 Standard Test Method for Density or Relative Density of Light Hydrocarbons by Pressure Hydrometer (ASTM Test Method D1657)
MPMS Chapter 9.3 Standard Test Method for Density, Relative Density, and API Gravity of Crude Petroleum and Liquid Petroleum Products by Thermohydrometer Method (ASTM Test Method D6822)
MPMS Chapter 10.1 Standard Test Method for Sediment in Crude Oils and Fuel Oils by the Extraction Method (ASTM Test Method D473)
MPMS Chapter 10.2 Standard Test Method for Water in Crude Oil by Distillation (ASTM Test Method D4006)
MPMS Chapter 10.3 Standard Test Method for Water and Sediment in Crude Oil by the Centrifuge Method (Laboratory Procedure) (ASTM Test Method D4007)
MPMS Chapter 10.4 Standard Test Method for Water and Sediment in Crude Oil by the Centrifuge Method (Laboratory Procedure)
MPMS Chapter 10.7 Standard Test Method for Water in Crude Oils by Potentiometric Karl Fischer Titration (ASTM Test Method D4377)
MPMS Chapter 10.8 Standard Test Method for Water in Crude Oils by Potentiometric Karl Fischer Titration (ASTM Test Method D4807)
MPMS Chapter 10.9 Standard Test Method for Water in Crude Oils by Coulometric Karl Fischer Titration (ASTM Test Method D4928)
MPMS Chapter 14.6 Pressure Pycnometer
MPMS Chapter 17.1 Guidelines for Marine Cargo Inspection
MPMS Chapter 17.2 Measurement of Cargoes Aboard Marine Tank Vessels
MPMS Chapter 18.1 Measurement Procedures for Crude Oil Gathered from Small Tanks By Truck

2.3 Gas Processors Association (GPA) Standards:
GPA S 2174 Obtaining Liquid Hydrocarbon Samples for Analysis by Gas Chromatograph

2.4 Other Publications:
UOP163 Hydrogen Sulfide and Mercaptan Sulfur in Liquid Hydrocarbons by Potentiometric Titration
49 CFR 173 Shippers - General Requirements for Shipments and Packagings

3. Terminology
3.1 Definitions:
3.1.1 assay, n - the procedure to determine the presence, absence, or quantity of one or more components.

3.1.2 automatic sampler, n - a device used to extract a representative sample from the liquid flowing in a pipe; the automatic sampler generally consists of a probe, a sample extractor, an associated controller, a flow measuring device, and a sample receiver.

3.1.3 bubble point, n - the pressure at which the first bubble of vapor forms is the bubble point when the pressure is lowered on a liquid held at a constant temperature.

3.1.3.1 Discussion - Bubble point pressures are higher at high temperatures.

3.1.4 density, n - for a quantity of a homogeneous substance, the ratio of its mass to its volume. The density varies as the temperature changes and is, therefore, generally expressed as the mass per unit of volume at a specified temperature.

3.1.5 dissolved water, n - water in solution in petroleum and petroleum products.

3.1.6 emulsion, n - a suspension of fine particles or globules, or both, of one or more liquids in another liquid.

3.1.7 entrained water, n - water suspended in the petroleum and petroleum products. Entrained water includes emulsions but does not include dissolved water.

3.1.8 free water, n - water that exists as a separate phase.

3.1.9 flash point, n - in petroleum products, the lowest temperature corrected to a barometric pressure of 101.3 kPa (760 mm Hg), at which application of an ignition source causes the vapors of a specimen of the sample to ignite under specified conditions of test.

3.1.10 floating piston (variable volume) cylinder (FPC), n - a high pressure sample container, with a free floating internal piston that effectively divides the container into two separate compartments.

3.1.11 high pressure cylinder, n - a receptacle used for storage and transportation of a sample obtained at pressures above atmospheric pressure.

3.1.12 inert gas, n - a gas that does not react with its surroundings.

3.1.13 inerting, v - a procedure used to reduce the oxygen content of the vapor spaces by introducing an inert gas such as nitrogen or carbon dioxide or a mixture of gases such as processed flue gas.

3.1.14 intermediate sample container, n - a container into which all or part of the sample from a primary container (receiver) is transferred for transport, storage, or ease of handling.

3.1.15 LPG (liquefied petroleum gas), n - narrow boiling range hydrocarbon mixtures consisting mainly of propane or propylene, or both, and butanes or butylenes, or both, plus limited amounts of other hydrocarbons and naturally-occurring non-hydrocarbons.

3.1.16 maximum fill density (reduced fill density), n - the volume of a container occupied by the sample, usually expressed as a percentage of the total capacity. Transportation legislation such as U.S. CFR 49, Canadian Transportation of Dangerous Goods Regulations, and IATA regulations limit the percent fill of containers used for shipping LPG and may quote this requirement as a reduced fill density or maximum fill density (normally 80 % maximum liquid fill at 15°C). Lower percent fill (lower fill density) may be required if sampling at lower temperatures.

3.1.17 on-board quantity (OBQ), n - the material present in a vessel's cargo tanks, void spaces, and pipelines before the vessel is loaded. On-board quantity may include any combination of water, oil, slops, oil residue, oil/water emulsion, and sediment.

3.1.18 outage tube (internal), n - a "cut to length" tube placed inside of the cylinder used as a way to remove excess sample from the cylinder via manual evacuation after the sample cylinder assembly is removed from the sample point. Refer to Fig. 1 and Fig. 2.

3.1.19 portable manual sampling unit, PSU, n - an intrinsically safe device used in conjunction with a vapor control valve to obtain required cargo samples under closed or restricted system conditions. Refer to Fig. 3 and Fig. 4.

3.1.20 primary sample container, n - a container in which a sample is initially collected.

3.1.20.1 Discussion - Examples of primary sample containers include glass and plastic bottles, cans, core-type thief, and fixed and portable sample containers (receivers).

3.1.21 remaining on board, ROB, n - the material remaining in a vessel's cargo tanks, void spaces, and pipelines after the cargo is discharged. Remaining on board quantity may include any combination of water, oil, slops, oil residue, oil/water emulsions, and sediment.

3.1.22 sample, n - a portion extracted from a total volume that may or may not contain the constituents in the same proportions that are present in that total volume.

3.1.23 sample loop (fast loop or slip stream), n - a low volume bypass diverted from the main pipeline.

3.1.24 sampling, v - all the steps required to obtain a sample that is representative of the contents of any pipe, tank, or other vessel and to place that sample in a container from which a representative test specimen can be taken for analysis.

3.1.25 slip tube, n - a graduated hollow rod fitted into a gas-tight housing, the lower end of which is open to the cargo's contents and the upper end is fitted with a valve.

3.1.26 standpipes, n - the vertical sections of pipe or tubing used for gauging extending from the gauging platform to near the bottom of tanks that are equipped with external or internal floating roofs. Standpipes may also be found on marine vessels. Standpipes are also known as "stilling wells" or "gauge wells". Standpipes without slots do not allow the free flow of product through the standpipe, and are known as solid or unslotted standpipes.

3.1.27 ullage (outage), n - the volume of available space in a container unoccupied by contents.

3.1.28 vapor control valve, VCV, n - a valve fitted on a standpipe, expansion trunk, or the deck that permits use of the portable handheld gauging/sampling instruments while restricting the release of vapors into the atmosphere.

3.1.29 vapor pressure, n - the pressure exerted by the vapor of a liquid when in equilibrium with the liquid.

3.1.29.1 Reid vapor pressure, RVP, n - resultant total pressure reading, corrected for measuring error, of a specific empirical test method (Test Method D323) for measuring the vapor pressure of gasoline and other volatile products.

3.1.29.2 true vapor pressure, TVP, n - the pressure at which the fluid is in equilibrium between its liquid and gas state. Sample Types

3.1.30 all-levels sample, n - a sample obtained by lowering the closed sampling device to the bottom of the outlet suction level, but always above free water, then opening the sampler and raising it at a uniform rate such that it is between 70 and 85 % full when withdrawn from the product. Alternatively, all-levels samples may be taken with samplers designed for filling as they pass downward through the product.

3.1.30.1 Discussion - If required by the test method, the sampler may be greater than 85 % full when withdrawn but in no case shall it be completely full. In these cases, take special handling precautions to consider the hazards associated with product thermal expansion.

3.1.31 boring sample, n - a sample of the material contained in a barrel, case, bag, or cake that is obtained from the chips created by boring holes into the material with a ship auger.

3.1.32 bottom sample, n - a spot sample collected from the material at the bottom of the tank, container, or line at its lowest point. In practice, the term bottom sample has a variety of meanings. As a result, it is recommended that the exact sampling location (for example 15 cm (6 in.) from the bottom) should be specified when using this term. See Fig. 5.

3.1.33 bottom water sample, n - a spot sample of free water taken from beneath the petroleum contained in a ship or barge compartment or a storage tank.

3.1.34 clearance sample, n - a spot sample taken with the inlet opening of the sampling device 10 cm (4 in.) (some regulatory agencies require 15 cm (6 in.)) below the bottom of the tank outlet. This term is normally associated with small (159 m3 (1000 barrels) or less) tanks, commonly referred to as lease tanks.

3.1.35 composite sample, n - a sample prepared by combining a number of samples and treated as a single sample. Also refer to "tank composite sample", "volumetric composite sample", "deck composite sample", and "multiple tank composite sample" definitions.

3.1.36 core sample, n - a sample of uniform cross-sectional area taken at a given height in a tank.

3.1.37 dead bottom sample, n - a sample obtained from the lowest accessible point in a tank. This is typically directly from the floor (or datum plate) of the shore tank or the bottom of the vessel compartment.

3.1.38 deck composite sample, n - a sample typically made by compositing a portion of each sample obtained from all vessel compartments containing a particular product grade.

3.1.39 dipper sample, n - a sample obtained by placing a dipper or other collecting vessel in the path of a free-flowing stream to collect a definite volume from the full cross section of the stream at regular time intervals for a constant time rate of flow or at time intervals varied in proportion to the flow rate.

3.1.40 drain sample, n - a sample obtained from the water draw-off valve on a storage tank vessel or container. Occasionally, a drain sample may be the same as a bottom sample (for example, in the case of a tank car).

3.1.41 floating roof sample, n - a spot sample taken just below the surface to determine the density (API gravity) of the liquid on which the roof is floating.

3.1.42 grab sample, n - (a) solid - a sample obtained by collecting equal quantities from parts or packages of a shipment of loose solids so that the sample is representative of the entire shipment. (b) liquid - a sample collected at a specific location in a tank or from a flowing stream in a pipe at a specific time.

3.1.43 grease sample, n - obtained by scooping or dipping a quantity of soft or semi-liquid material contained from a package in a representative manner.

3.1.44 loading zone sample, n - a sample taken from a tank prior to commencement of a transfer, intended to represent only the product expected to be transferred.

3.1.45 lower sample, n - a spot sample of liquid from the middle of the lower one-third of the tank's content (a distance of five-sixths of the depth liquid below the liquid's surface). See Fig. 5.

3.1.46 middle sample, n - a spot sample taken from the middle of a tank's contents (a distance of one half of the depth of liquid below the liquid's surface). See Fig. 5.

3.1.47 multiple tank composite sample, n - a mixture of individual samples or composites of samples that have been obtained from several tanks or ship/barge compartments containing the same grade of material. The mixture is blended typically in proportion to the volume of material contained in the respective tanks or compartments.

3.1.48 representative sample, n - a portion extracted from the total volume that contains the constituents in the same proportions that are present in that total volume.

3.1.49 running sample, n - a sample obtained by lowering an open sampling device to the bottom of the outlet suction level, but always above free water, and returning it to the top of the product at a uniform rate such that the sampling device is between 70 and 85 % full when withdrawn from the product.

3.1.49.1 Discussion - If required by the test method, the sampler may be greater than 85 % full when withdrawn but in no case shall it be completely full. In these cases, take special handling precautions to consider the hazards associated with product thermal expansion.

3.1.50 spot sample, n - a sample taken at a specific location in a tank or from a flowing stream in a pipe at a specific time.

3.1.51 suction sample (outlet), n - a spot sample taken at the lowest level from which product is expected to be pumped from the tank; see Fig. 5.

3.1.52 sump sample, n - spot sample taken from within the tank or vessel compartment sump; see Fig. 5.

3.1.53 surface sample (skim sample), n - a spot sample skimmed from the surface of a liquid in a tank. See Fig. 5.

3.1.54 tank composite sample, n - a blend created from a single tank, as an example combining the upper, middle, and lower samples. For a tank of uniform cross section, such as an upright cylindrical tank, the blend consists of equal parts of the three samples. A combination of other samples may also be used, such as running, all-levels or additional spot samples. For a horizontal cylindrical tank, the blend consists of samples in the proportions shown in Table 1.

3.1.55 tank tap sample, n - a spot sample taken from a sample tap on the side of a tank. It may also be referred to as a tank-side sample.

3.1.56 test specimen, n - a representative sub-sample taken from the primary or intermediate sample container for analysis.

3.1.57 top sample, n - a spot sample obtained 15 cm (6 in.) below the top surface of the liquid. See Fig. 5.

3.1.58 tube sample (thief sample), n - a sample obtained with a sampling tube or special thief, either as a core sample or spot sample, from a specific point in the tank or container.

3.1.59 upper sample, n - a spot sample taken from the middle of the upper one third of the tank's contents (a distance of one-sixth of the depth of the liquid below the liquid's surface). See Fig. 5.

3.1.60 volumetric composite sample, n - a sample consisting of measured proportional parts from each zone if it is for a single tank. If the volumetric composite is for multiple tanks, or vessel compartments, it consists of measured proportional parts from each tank or compartment sampled.

3.1.61 zone sample, n - a sample taken as that part of the liquid column that is trapped within the whole height of a sampling device when it is sealed at a single spot location within a tank after having been fully flushed as it was lowered to that position.