Manual of PetroleumMeasurement StandardsChapter 9—Density Determination

Section 3—Standard Test Method for Density, Relative Density, and API Gravity of Crude Petroleum and Liquid Petroleum Products by Thermohydrometer Method

SECOND EDITION, NOVEMBER 2002

Manual of PetroleumMeasurement StandardsChapter 9—Density Determination

Section 3—Standard Test Method for Density, Relative Density, and API Gravity of Crude Petroleum and Liquid Petroleum Products by Thermohydrometer Method

Measurement Coordination

SECOND EDITION, NOVEMBER 2002

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iii

CONTENTS

Page

1 SCOPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

2 REFERENCED DOCUMENTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

3 TERMINOLOGY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

4 SUMMARY OF TEST METHOD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

5 SIGNIFICANCE AND USE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

6 APPARATUS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

7 PROCEDURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

8 REPORTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

9 PRECISION AND BIAS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

10 KEYWORDS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Figures1 Typical Thermohydrometer Designs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Hydrometer Reading for Transparent Fluids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Hydrometer Reading for Opaque Fluids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Tables1 Density Thermohydrometers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 API Gravity Thermohydrometers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Limiting Conditions and Test Temperatures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

v

Designation: D 6822 – 02

Designation: Manual of Petroleum Measurement Standards (MPMS), Chapter 9.3

An American National Standard

Standard Test Method forDensity, Relative Density, and API Gravity of CrudePetroleum and Liquid Petroleum Products byThermohydrometer Method1

This standard is issued under the fixed designation D 6822; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.

1. Scope

1.1 This test method covers the determination, using a glassthermohydrometer, of the density, relative density (specificgravity), or API gravity of crude petroleum and liquid petro-leum products with Reid vapor pressures of 101.325 kPa(14.696 psi) or less. Values are determined at existing tempera-tures and corrected to 15°C or 60°F by means of internationalstandard tables.

1.2 The values stated in either SI units or inch pound-unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in nonconformancewith the standard.

1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.

2. Referenced Documents

2.1 ASTM Standards:D 1298 Test Method for Density, Relative Density (Specific

Gravity), or API Gravity of Crude Petroleum and LiquidPetroleum Products by Hydrometer Method (API MPMSChapter 9.1)2

D 6300 Practice for Determination of Precision and BiasData for Use in Test Methods for Petroleum Products andLubricants2

E 100 Specification for ASTM Hydrometers3

2.2 Adjunct:Adjunct to D 1250 Guide for Petroleum Measurement

Tables (API MPMS Chapter 11.1)4

2.3 API Standards:5

MPMS Chapter 9.1 Hydrometer Test Method for Density,Relative Density (Specific Gravity) or API Gravity ofCrude Petroleum and Liquid Petroleum Products (ASTMTest Method D 1298)

MPMS Chapter 11.1 Volume Correction Factors

3. Terminology

3.1 Definitions of Terms Specific to This Standard:3.1.1 API gravity (°API), n—a special function of relative

density 60/60°F, represented by:

°API 5 @141.5 / ~relative density 60/60°F!# 2 131.5 (1)

3.1.1.1 Discussion—No statement of reference temperatureis required, as 60°F is included in the definition.

3.1.2 density, n—the mass of liquid per unit volume at 15°Cand 101.325 kPa with the standard unit of measurement beingkilograms per cubic metre (kg/m3).

3.1.2.1 Discussion—Other reference temperatures, such as20°C may be used for some products or in some locations. Lesspreferred units of measurement; for example, kg/L or g/mL, arestill in use.

3.1.3 observed values, n—hydrometer readings observed ata temperature other than the defined reference temperature.

3.1.3.1 Discussion—These values are only hydrometerreadings and not density, relative density, or API gravity at thetemperature.

3.1.4 relative density, n—the ratio of the mass of a givenvolume of liquid at a specific temperature to the mass of anequal volume of pure water at the same or different tempera-ture. Both reference temperatures shall be explicitly stated.

3.1.4.1 Discussion—Common reference temperatures in-clude 15/15°C, 60/60°F, 20/20°C, and 20/4°C. The historicterm specific gravity may still be found.

3.1.5 thermohydrometer, n—a glass hydrometer with a1 This test method is under the jurisdiction of ASTM Committee D02 on

Petroleum Products and Lubricants and the API Committee on Petroleum Measure-ment, and is the direct responsibility of Subcommittee D02.02/COMQ, the jointASTM-API Committee on Static Petroleum Measurement.

Current edition approved Aug. 10, 2002. Published November 2002.2 Annual Book of ASTM Standards, Vol 05.04.3 Annual Book of ASTM Standards, Vol 14.03.

4 Annual Book of ASTM Standards, Vol 05.01.5 Available from American Petroleum Institute, 1220 L St., NW, Washington, DC

20005.

1

self-contained thermometer.

4. Summary of Test Method

4.1 The density or API gravity, after temperature equilib-rium has been reached, is read by observing the freely floatingthermohydrometer and noting the graduation nearest to theapparent intersection of the horizontal plane surface of theliquid with the vertical scale of the hydrometer after tempera-ture equilibrium has been reached. The observed thermohy-drometer reading is reduced to the reference temperature valueby means of the Petroleum Measurement Tables (the appropri-ate adjunct to Guide D 1250/API MPMS Chapter 11.1) andobserved temperature from the enclosed thermometer.

5. Significance and Use

5.1 Density and API gravity are used in custody transferquantity calculations and to satisfy transportation, storage, andregulatory requirements. Accurate determination of density orAPI gravity of crude petroleum and liquid petroleum productsis necessary for the conversion of measured volumes tovolumes at the standard temperatures of 15°C or 60°F.

5.2 Density and API gravity are also factors that indicate thequality of crude petroleum. Crude petroleum prices are fre-quently posted against values in kg/m3 or in degrees API.However, this property of petroleum is an uncertain indicationof its quality unless correlated with other properties.

5.3 Field of Application—Because the thermohydrometerincorporates both the hydrometer and thermometer in onedevice, it is more applicable in field operations for determiningdensity or API gravity of crude petroleum and other liquidpetroleum products. The procedure is convenient for gatheringmain trunk pipelines and other field applications where limitedlaboratory facilities are available. The thermohydrometermethod may have limitations in some petroleum densitydeterminations. When this is the case, other methods such asTest Method D 1298 (API MPMS Chapter 9.1) may be used.

5.4 This test method is suitable for determining the density,relative density, or API gravity of low viscosity transparent oropaque liquids, or both. This test method, when used foropaque liquids, requires the use of a meniscus correction (see7.2).

6. Apparatus

6.1 Glass Thermohydrometers, as specified in SpecificationE 100 (shown in Fig. 1), and graduated in:

6.1.1 Kilograms/cubic metre (kg/m3) and degrees Celsiusfor density hydrometers, as shown in Table 1.

6.1.2 Degrees API (°API) and degrees Fahrenheit for hy-drometers measuring in API Gravity, as shown in Table 2.

6.2 Hydrometer Cylinders, clear glass, plastic, or metal. Forconvenience of pouring, the cylinder may have a pouring lip.The inside diameter shall be at least 25 mm (1 in.) greater thanthe outside diameter of the thermohydrometer used. The heightof the cylinder shall be such that the bottom of the thermohy-drometer clears the bottom of the cylinder by at least 25 mm(1 in.) when suspended in the sample test portion.

6.2.1 For field testing, a sample thief of suitable dimensionsmay be more convenient than a hydrometer cylinder. Theliquid level shall be level with the top of the thief.

6.3 Temperature Bath, to control temperature close to thebulk hydrocarbon temperature or to control temperature closeto the reference temperature of 15°C or 60°F.

7. Procedure

7.1 Effect of Test Temperature:7.1.1 The density or API gravity determined by the thermo-

hydrometer method is most accurate at or near the referencetemperature of 15°C or 60°F. Other temperatures within therange of the enclosed thermometer may be used, if consistentwith the type of sample and the necessary limiting conditionsshown in Table 3.

7.1.2 If the test temperature is significantly different fromthe reference temperature of 15°C or 60°F, the expansion orcontraction of the glass may affect the calibration of thethermohydrometer. A hydrometer correction factor (HYC) maybe applied to the measured density value to provide a correctedreading. Historically, the following equations have been usedwithin volume correction factor tables.

rcorrected 5 rtest 3 HYC (2)

TABLE 1 Density Thermohydrometers

ASTM Hydrometer No. Density, Range, kg/m3

300H 600 to 650301H 650 to 700302H 700 to 750303H 750 to 800304H 800 to 850305H 850 to 900306H 900 to 950307H 950 to 1000308H 1000 to 1050309H 1050 to 1100

Hydrometer

Total length, mm 374 to 387Body diameter, mm 18 to 25Stem diameter, mm, min 4.0

Hydrometer Scale

Standard temperature, °C 15Subdivisions, kg/m3 0.5Short intermediate lines at, kg/m3 1Long intermediate lines at, kg/m3 5Main (numbered) lines at, kg/m3 10Scale error at any point not to exceed, kg/m3 0.5Length of nominal scale, mm 125 to 145Scale extension beyond nominal range limits, kg/m3 2.5

Thermometer Scale

Range, °CDesignation L −20 to +65Designation M 0 to +85Designation H +20 to +105

Immersion totalSubdivisions, °C 1.0Intermediate lines at, °C 5Main (numbered) lines at, °C 10Scale error at any point not to exceed, °C 1.0Scale length, mm 80 to 100

D 6822 – 02

2

TABLE 2 API Gravity Thermohydrometers

NOTE—For petroleum products and other liquids of similar surface tensions (33 dynes/cm or less).

Thermometer Scale in Body Thermometer Scale in Stem

ASTM HydrometerNo.

Nominal API GravityRange, degrees

ASTM HydrometerNo.

Nominal API GravityRange, degrees

41H-66 15 to 23 71H-62 −1 to +1142H-66 22 to 30 72H-62 9 to 2143H-66 29 to 37 73H-62 19 to 3144H-66 36 to 44 74H-62 29 to 4145H-66 43 to 5151H-62 −1 to +1152H-62 9 to 2153H-62 19 to 3154H-62 29 to 4155H-62 39 to 5156H-62 49 to 6157H-62 59 to 7158H-62 69 to 8159H-62 79 to 9160H-62 89 to 101

Hydrometer

Thermometer Scalein Body

Thermometer Scalein Stem

Total length, mm 374 to 387 374 to 387Body diameter, mm 18 to 25 23 to 27Stem diameter, mm, min 4.0 6.0

Hydrometer Scale

Standard temperature, °F 60Subdivisions, °API 0.1Intermediate lines at, °API 0.5Main (numbered) lines at, °API 1.0Scale error at any point not to exceed, °API 0.1Length of nominal scale, mm 125 to 145

Thermometer Scale

Thermometer Scalein Body

Thermometer Scalein Stem

Range, °FA

Designation L 0 to 150Designation M 30 to 180 30 to 220Designation H 60 to 220

Immersion Total TotalSubdivisions, °F 2 2Intermediate lines at, °F 10 10Main (numbered) lines at, °F 20 20Scale error at any point not to exceed, °F 1 1Scale length, mm 80 to 110 105 to 145

A Indication of the thermometer range is made by the use of the listed designation used as a suffix to the ASTM hydrometer number. For example, 54HL is an instrumentwith an API gravity range of 29 to 41°API and a thermometer range of 0 to 150°F. An instrument with the same gravity range but a thermometer range of 60 to 220°F wouldbe designated 54HH. The number 57HM would identify an instrument with an API gravity range of 59 to 71°API and a thermometer range of 30 to 180°F.

TABLE 3 Limiting Conditions and Test Temperatures

Sample Type Initial Boiling Point Other Limits Test Temperature

Volatile 120°C (250°F) or lower Cool in original closed container to 18°C (65°F) or lower

Volatile and viscous 120°C (250°F) or lower Viscosity too highat 18°C (65°F)

Heat to minimum temperature to obtain sufficient fluidity

Non-volatile Above 120°C (250°F) Use any temperature between −18°C and 90°C (0 and 195°F)as convenient

Mixture with non-petroleum products . . . Test at 15 6 0.2°C or 60 6 0.5°F

D 6822 – 02

3

FIG. 1 Typical Thermohydrometer Designs

D 6822 – 02

4

where:HYC = hydrometer thermal correction factor,rcorrected = test density, corrected for the effects of tem-

perature on the thermohydrometer, andrtest = test density, as observed by reading the ther-

mohydrometer.

HYC 5 1 2 0.00001278~t 2 60! 2 0.0000000062~t 2 60!2 (3)

where:t = observed temperature (°F) or

HYC 5 1 2 0.000023~t 2 15! 2 0.00000002~t 2 15!2 (4)

where:t = observed temperature (°C).

7.1.2.1 All parties affected by the measurement shouldagree upon the need for and the method of correction.

7.1.3 When the thermohydrometer value is used to selectfactors for correcting volumes to standard temperatures, thethermohydrometer reading preferably should be made at atemperature within 63°C (65°F) of the temperature at whichthe bulk volume of the oil was measured (see Note 1).However, when appreciable amounts of light fractions may belost during determination at the bulk oil temperature, the limitsgiven in Table 3 shall be applied.

NOTE 1—Volume and density correction tables are based on averageexpansion for a number of typical materials. Since the same coefficientswere used in computing both sets of tables, corrections made over thesame temperature interval minimize errors arising from possible differ-ences between the coefficients of the material under test and the standardcoefficients. This effect becomes more important as temperatures divergesignificantly from 15°C or 60°F.

7.2 Density Measurement:7.2.1 Adjust the temperature of the sample in accordance

with Table 3. For field testing, test temperatures other thanthose listed in Table 3 may be used, however, accuracy may besacrificed. The hydrometer cylinder shall be at approximatelythe same temperature as the sample to be tested.

7.2.2 Transfer the sample into the clean hydrometer cylinderwithout splashing, so as to avoid the formation of air bubblesand to reduce, to a minimum, the evaporation of the lowerboiling constituents of the more volatile samples (Warning—Extremely flammable. Vapors may cause a flash fire). For themore volatile samples, transfer to the hydrometer cylinder bysiphoning (Warning—Siphoning by mouth could result iningestion of sample). Use a rubber aspirator bulb to siphon themore volatile samples. Remove any air bubbles formed, afterthey have collected on the surface of the sample, by touchingthem with a piece of clean absorbent paper before inserting thethermohydrometer. For field testing, the thermohydrometermay be inserted directly into a sampling thief. Place thecylinder containing the sample in a vertical position in alocation free from air currents. Take precautions to prevent thetemperature of the sample from changing appreciably duringthe time necessary to complete the test.

7.2.2.1 During this period, the temperature of the surround-ing medium should not change more than 3°C (5°F).

7.2.3 Lower and raise the thermohydrometer no more thantwo scale divisions in the sample cylinder to minimize vapor

loss and in such a manner that the stem will not be wettedhigher than the approximate floating position.

7.2.3.1 Keep the rest of the stem dry, as unnecessary liquidon the stem changes the effective weight of the instrument, andso affects the reading obtained.

7.2.3.2 Gently lower the thermohydrometer into the centerof the hydrometer cylinder. When the thermohydrometer hassettled, ensure it is not resting on the bottom of the cylinder bydepressing it about two scale divisions into the liquid. Give thethermohydrometer a slight spin, allowing it to float freely awayfrom the walls of the hydrometer cylinder.

7.2.3.3 Allow enough time for the thermohydrometer tocome to rest, all air bubbles to come to the surface, and thethermohydrometer temperature to stabilize, usually 3 to 5 min.This is particularly necessary in the case of more viscoussamples. Use a temperature bath if control of the sampletemperature is required.

7.2.4 Read the thermohydrometer to the nearest scale divi-sion (see 7.2.7 for details). The correct reading is that point onthe thermohydrometer scale at which the surface of the liquidcuts the scale. To make a reading for transparent liquids in atransparent hydrometer cylinder, determine this point by plac-ing the eye slightly below the level of the liquid and slowlyraising it until the surface, first seen as a distorted ellipse,appears to become a straight line cutting the thermohydrometerscale. See Fig. 2 for details on reading the meniscus.

7.2.5 To make a reading with opaque liquids, observe thepoint on the thermohydrometer scale to which the sample risesabove its main surface, placing the eye slightly above the planesurface of the liquid. This reading requires meniscus correction(see Note 2). Determine this correction for the particularthermohydrometer in use by observing the height above themain surface of the liquid to which the sample rises on thethermohydrometer scale when the thermohydrometer in ques-tion is immersed in a transparent liquid having a surfacetension similar to that of a sample under test. Refer to Fig. 3 fordetails of reading the meniscus.

NOTE 2—When determination of the actual meniscus correction is notpractical, industry practice has been to add 0.5 kg/m3 to the densityreading or to subtract 0.1°API from the API reading.

7.2.6 Read and record the thermohydrometer scale readingwith meniscus correction to the nearest 0.5 kg/m3 or 0.1°APIand the thermometer reading to the nearest 0.5°C (1.0°F).

7.2.7 It may be difficult to ensure that the temperature of thethermohydrometer and liquid has stabilized. To provide thisassurance, two successive determinations of density or gravitymay be made with the same liquid and each determinationcorrected to 15°C (60°F). The two successive corrected valuesshould be within 0.5 kg/m3 or 0.1°API to be acceptable. If thisrepeatability cannot be obtained, the temperature may not havestabilized or loss of light hydrocarbons may be occurring.

7.2.8 Gradually withdraw and wipe the thermohydrometerto expose the thermometer scale until a reading can be made.Always make sure the thermometer bulb remains in the liquidwhen reading the temperature. Read the temperature to thenearest 0.5°C (1.0°F).

D 6822 – 02

5

8. Reports

8.1 Reporting of Observed Readings:8.1.1 Apply any relevant corrections to the observed ther-

mohydrometer reading.8.1.1.1 For opaque samples, make the appropriate correc-

tion to the observed thermohydrometer scale reading given in7.2.5.

8.1.2 Record this corrected hydrometer scale reading to thenearest 0.5 kg/m3 density or 0.1°API and record the thermom-eter reading to the nearest 0.5°C or 1.0°F.

8.2 Correction to Standard Temperatures:

8.2.1 To correct density or API gravity to standard tempera-tures at 15°C or 60°F respectively, use the following PetroleumMeasurement Tables.

8.2.1.1 When a density scale thermohydrometer was em-ployed, use Tables 53A, 53B, or 53D from the appropriateadjuncts to Guide D 1250 (API MPMS Chapter 11.1) to obtaindensity at 15°C.

8.2.1.2 When an API scale thermohydrometer was em-ployed, use Tables 5A, 5B, or 5D from the appropriate adjunctsto Guide D 1250 (API MPMS Chapter 11.1) to obtain thegravity in °API.

FIG. 2 Hydrometer Reading for Transparent Fluids

FIG. 3 Hydrometer Reading for Opaque Fluids

D 6822 – 02

6

8.2.1.3 When a relative density scale thermohydrometerwas employed, use Tables 23A and 23B from the appropriateadjuncts to Guide D 1250 (API MPMS Chapter 11.1) to obtainthe relative density at 60/60°F.

8.3 Unit Conversions:8.3.1 When a value is obtained with a thermohydrometer

scaled in one set of units and a result is required in another setof units, convert by use of the appropriate Petroleum Measure-ment Tables.

8.3.1.1 For conversion from density at 15°C to other units,use Table 5 in the appropriate adjunct to Guide D 1250 (APIMPMS Chapter 11.1).

8.3.1.2 For conversion from API gravity to other units, useTable 3 in the appropriate adjunct to Guide D 1250 (APIMPMS Chapter 11.1).

8.4 Reporting of Final Value—Report the final value asdensity at 15°C to the nearest 0.5 kg/m3, relative density60/60°F to the nearest 0.0005, or as °API to the nearest0.1°API, whichever is applicable.

9. Precision and Bias

9.1 Precision—The precision of this test method as deter-mined by statistical examination of interlaboratory results is asfollows:

9.1.1 Repeatability—The difference between two results,

obtained by the same operator with the same apparatus underconstant operating conditions on identical test material, wouldin the long run, in the normal and correct operation of the testmethod, exceed 0.6 kg/m3 or 0.2°API only in one case intwenty.

9.1.2 Reproducibility—The difference between two singleand independent results obtained by different operators work-ing in different laboratories and on identical test materialwould, in the long run, in the normal and correct operation ofthe test method, exceed 1.5 kg/m3 or 0.5°API only in one casein twenty.

NOTE 3—The precision of this test method was not obtained inaccordance with Practice D 6300. The precision statement applies only tomeasurements made at temperatures of 15 6 10°C or 60 6 15°F.

9.2 Bias—Bias for this test method has not been deter-mined. However, to determine that the bias is within acceptablelimits, ensure the hydrometer and the thermometer have beenverified using standards traceable to International Standardsbefore the thermohydrometer or hydrometer and thermometerare placed into service. Periodic re-verification may be re-quired.

10. Keywords

10.1 API gravity; density; hydrometer; hydrometer cylin-der; relative density; thermohydrometer; thermometer

D 6822 – 02

7

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Mail Orders – Payment by check or money order in U.S. dollars is required except for established accounts. State and local taxes, $10 processing fee*, and 5% shipping must be added. Sendmail orders to: API Publications, Global Engineering Documents, 15 Inverness Way East, M/S C303B, Englewood, CO 80112-5776, USA.Purchase Orders – Purchase orders are accepted from established accounts. Invoice will include actual freight cost, a $10 processing fee*, plus state and local taxes.Telephone Orders – If ordering by telephone, a $10 processing fee* and actual freight costs will be added to the order.Sales Tax – All U.S. purchases must include applicable state and local sales tax. Customers claiming tax-exempt status must provide Global with a copy of their exemption certificate.Shipping (U.S. Orders) – Orders shipped within the U.S. are sent via traceable means. Most orders are shipped the same day. Subscription updates are sent by First-Class Mail. Other options,including next-day service, air service, and fax transmission are available at additional cost. Call 1-800-854-7179 for more information.Shipping (International Orders) – Standard international shipping is by air express courier service. Subscription updates are sent by World Mail. Normal delivery is 3-4 days from shipping date.Rush Shipping Fee – Next Day Delivery orders charge is $20 in addition to the carrier charges. Next Day Delivery orders must be placed by 2:00 p.m. MST to ensure overnight delivery.Returns – All returns must be pre-approved by calling Global’s Customer Service Department at 1-800-624-3974 for information and assistance. There may be a 15% restocking fee. Special orderitems, electronic documents, and age-dated materials are non-returnable.*Minimum Order – There is a $50 minimum for all orders containing hardcopy documents. The $50 minimum applies to the order subtotal including the $10 processing fee, excluding anyapplicable taxes and freight charges. If the total cost of the documents on the order plus the $10 processing fee is less than $50, the processing fee will be increased to bring the order amountup to the $50 minimum. This processing fee will be applied before any applicable deposit account, quantity or member discounts have been applied. There is no minimum for orders containing onlyelectronically delivered documents.

APIAmerican Petroleum Institute

2002 Publications Order Form

H30181

Ch. 14.6, Continuous Density Measurement

$ 46.00

Ch. 9.2, Pressure Hydrometer Test Method for Density or Relative Density $ 46.00H30182

Ch. 9.1, Hydrometer Test Method for Density, Relative Density(Specific Gravity), or API Gravity of Crude Petroleum

and Liquid Petroleum Products

H30346 $ 97.00

There’s more where thiscame from.

The American Petroleum Institute provides additional resources and programs to the oil and natural gas industry which are based on APIStandards. For more information, contact:

• Monogram Licensing Program Phone: 202-962-4791Fax: 202-682-8070

• American Petroleum Institute Quality Registrar Phone: 202-962-4791(APIQR) Fax: 202-682-8070

• API Spec Q1 Registration Phone: 202-962-4791Fax: 202-682-8070

• Perforator System Registration Phone: 202-962-4791Fax: 202-682-8070

• Inspector Certification Programs Phone: 202-682-8161Fax: 202-962-4739

• Engine Oil Licensing and Certification System Phone: 202-682-8233(EOLCS) Fax: 202-962-4739

• Training/Workshops Phone: 202-682-8490Fax: 202-962-4797

Check out the API Publications, Programs, and Services Catalog online atwww.api.org.

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11/02

Additional copies are available through Global EngineeringDocuments at (800) 854-7179 or (303) 397-7956

Information about API Publications, Programs and Services isavailable on the World Wide Web at: http://www.api.org

Product No. H09032