oSIST prEN ISO 3104:2022

Petroleum products - Transparent and opaque liquids - Determination of kinematic viscosity and calculation of dynamic viscosity (ISO/DIS 3104:2022)

This document specifies Procedure A, using manual glass viscometers, and Procedure B, using glass capillary viscometers in an automated assembly, for the determination of the kinematic viscosity, ν, of liquid petroleum products, both transparent and opaque, by measuring the time for a volume of liquid to flow under gravity through a calibrated glass capillary viscometer. The dynamic viscosity, η, is obtained by multiplying the measured kinematic viscosity by the density, ρ, of the liquid. The range of kinematic viscosities covered in this test method is from 0,2 mm2/s to 300 000 mm2/s over the temperature range –20 °C to +150 °C. The products it is applicable to contain kerosene, diesel fuels, biodiesel fuels, and biodiesel fuel blends.

Mineralölerzeugnisse - Durchsichtige und undurchsichtige Flüssigkeiten - Bestimmung der kinematischen Viskosität und Berechnung der dynamischen Viskosität (ISO/DIS 3104:2022)

Produits pétroliers - Liquides opaques et transparents - Détermination de la viscosité cinématique et calcul de la viscosité dynamique (ISO/DIS 3104:2022)

Naftni proizvodi - Prozorne in neprozorne tekočine - Določanje kinematične viskoznosti in izračun dinamične viskoznosti (ISO/DIS 3104:2022)

General Information

• Status: Not Published
• Public Enquiry End Date: 02-Jan-2023
• ICS: 75.080 - Petroleum products in general
• Technical Committee: NAD - Petroleum products, lubricants and related products
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 02-Nov-2022
• Due Date: 22-Mar-2023
• Completion Date: 03-Jan-2023
• Ref Project: prEN ISO 3104 - Petroleum products - Transparent and opaque liquids - Determination of kinematic viscosity and calculation of dynamic viscosity (ISO/DIS 3104:2022)

Relations

• Revised: SIST EN ISO 3104:2020 - Petroleum products - Transparent and opaque liquids - Determination of kinematic viscosity and calculation of dynamic viscosity (ISO 3104:2020)
• Effective Date: 01-Dec-2022
• Revised: SIST EN ISO 3104:2020 - Petroleum products - Transparent and opaque liquids - Determination of kinematic viscosity and calculation of dynamic viscosity (ISO 3104:2020)
• Effective Date: 18-Jan-2023

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN ISO 3104:2022
01-december-2022
Naftni proizvodi - Prozorne in neprozorne tekočine - Določanje kinematične
viskoznosti in izračun dinamične viskoznosti (ISO/DIS 3104:2022)
Petroleum products - Transparent and opaque liquids - Determination of kinematic
viscosity and calculation of dynamic viscosity (ISO/DIS 3104:2022)

Mineralölerzeugnisse - Durchsichtige und undurchsichtige Flüssigkeiten - Bestimmung

der kinematischen Viskosität und Berechnung der dynamischen Viskosität (ISO/DIS
3104:2022)

Produits pétroliers - Liquides opaques et transparents - Détermination de la viscosité

cinématique et calcul de la viscosité dynamique (ISO/DIS 3104:2022)
Ta slovenski standard je istoveten z: prEN ISO 3104
ICS:
75.080 Naftni proizvodi na splošno Petroleum products in
general
oSIST prEN ISO 3104:2022 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 3104:2022
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oSIST prEN ISO 3104:2022
DRAFT INTERNATIONAL STANDARD
ISO/DIS 3104
ISO/TC 28 Secretariat: NEN
Voting begins on: Voting terminates on:
2022-10-21 2023-01-13
Petroleum products — Transparent and opaque liquids
— Determination of kinematic viscosity and calculation of
dynamic viscosity

Produits pétroliers — Liquides opaques et transparents — Détermination de la viscosité cinématique et

calcul de la viscosité dynamique
ICS: 75.080
This document is circulated as received from the committee secretariat.
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENT AND APPROVAL. IT IS
ISO/CEN PARALLEL PROCESSING
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
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STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 3104:2022(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION. © ISO 2022
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oSIST prEN ISO 3104:2022
ISO/DIS 3104:2022(E)
DRAFT INTERNATIONAL STANDARD
ISO/DIS 3104
ISO/TC 28 Secretariat: NEN
Voting begins on: Voting terminates on:
Petroleum products — Transparent and opaque liquids
— Determination of kinematic viscosity and calculation of
dynamic viscosity

Produits pétroliers — Liquides opaques et transparents — Détermination de la viscosité cinématique et

calcul de la viscosité dynamique
ICS: 75.080
This document is circulated as received from the committee secretariat.
COPYRIGHT PROTECTED DOCUMENT
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENT AND APPROVAL. IT IS
© ISO 2022
ISO/CEN PARALLEL PROCESSING
THEREFORE SUBJECT TO CHANGE AND MAY

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

NOT BE REFERRED TO AS AN INTERNATIONAL

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POTENTIAL TO BECOME STANDARDS TO
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Email: [e-mail]
NATIONAL REGULATIONS.
Website: www.iso.org ISO/DIS 3104:2022(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
Published in Switzerland
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
© ISO 2022 – All rights reserved
PROVIDE SUPPORTING DOCUMENTATION. © ISO 2022
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oSIST prEN ISO 3104:2022
ISO/DIS 3104:2022(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction .................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ..................................................................................................................................................................................... 1

3 Terms and definitions .................................................................................................................................................................................... 1

4 Principle ........................................................................................................................................................................................................................ 2

5 Reagents and materials ................................................................................................................................................................................ 2

6 Apparatus design and requirements .............................................................................................................................................3

7 Verification ................................................................................................................................................................................................................6

7.1 Viscometer .................................................................................................................................................................................................. 6

7.2 Liquid-in-glass thermometer ..................................................................................................................................................... 7

7.3 Digital contact thermometer ..................................................................................................................................................... 7

7.4 Timer ............................................................................................................................................................................................................... 7

8 Re-calibration ......................................................................................................................................................................................................... 7

9 Quality control ....................................................................................................................................................................................................... 7

10 Sample preparation ..........................................................................................................................................................................................8

10.1 Pre-analysis sample conditioning ......................................................................................................................................... 8

10.2 Visual inspection and filtering ................................................................................................................................................. 8

11 Procedure A — Manual equipment (Referee test method) .................................................................................... 8

12 Procedure B — Automated equipment .....................................................................................................................................10

13 Cleaning of the viscometer tube .......................................................................................................................................................11

14 Calculation ...............................................................................................................................................................................................................12

14.1 Procedure A — Manual viscometers ...............................................................................................................................12

14.2 Procedure B — Automated viscometers ...................................................................................................................... 13

15 Expression of results ....................................................................................................................................................................................13

16 Precision of procedure A ..........................................................................................................................................................................13

16.1 Determinability, d ............................................................................................................................................................................. 13

16.2 Repeatability, r..................................................................................................................................................................................... 14

16.3 Reproducibility, R .............................................................................................................................................................................. 14

17 Precision of Procedure B ..........................................................................................................................................................................15

17.1 Determinability, d ............................................................................................................................................................................. 15

17.2 Repeatability, r.....................................................................................................................................................................................15

17.3 Reproducibility, R ..............................................................................................................................................................................15

18 Test report ...............................................................................................................................................................................................................16

Annex A (normative) Viscometer types, calibration and verification ..........................................................................17

Annex B (normative) Thermometers for kinematic viscosity test ...................................................................................18

Annex C (normative) Conditioning of samples prior to manual or automated analysis ...........................22

Annex D (normative) Calculation of acceptable tolerance zone (band) to determine

conformance with a certified reference material (CRM) ......................................................................................24

Bibliography .............................................................................................................................................................................................................................25

iii
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oSIST prEN ISO 3104:2022
ISO/DIS 3104:2022(E)
Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards

bodies (ISO member bodies). The work of preparing International Standards is normally carried out

through ISO technical committees. Each member body interested in a subject for which a technical

committee has been established has the right to be represented on that committee. International

organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.

ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of

electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www.iso.org/patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to

the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see

www.iso.org/iso/foreword.html.

This document was prepared by Technical Committee ISO/TC 28, Petroleum and related products, fuels

and lubricants from natural or synthetic sources.

This third edition cancels and replaces the second edition (ISO 3104:1994), which has been technically

revised.
The main changes compared to the previous edition are as follows:
— precision data have been updated to all actual fuels on the market;
— biodiesel (FAME) blends and paraffinic diesel have been included in the scope;

— the procedure description and allowance of automated techniques have been included.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www.iso.org/members.html.
© ISO 2022 – All rights reserved
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Introduction

Many petroleum products, and some non-petroleum materials, are used as lubricants, and the correct

operation of equipment depends upon the appropriate viscosity of the liquid being used. In addition,

the viscosity of many petroleum fuels is important for the estimation of optimum storage, handling

and operational conditions. Thus, the accurate measurement of viscosity is essential to many product

specifications.

This document describes two test methods: Procedure A Manual and Procedure B Automated.

Procedure A is the referee test method (or reference test method) to resolve doubts or dispute.

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oSIST prEN ISO 3104:2022
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oSIST prEN ISO 3104:2022
DRAFT INTERNATIONAL STANDARD ISO/DIS 3104:2022(E)
Petroleum products — Transparent and opaque liquids
— Determination of kinematic viscosity and calculation of
dynamic viscosity

WARNING — This document does not purport to address all of the safety problems, if any,

associated with its use. It is the responsibility of users of this document to take appropriate

measures to ensure the safety and health of personnel prior to the application of this document,

and to determine the applicability of any other restrictions.
1 Scope

This document specifies Procedure A, using manual glass viscometers, and Procedure B, using glass

capillary viscometers in an automated assembly, for the determination of the kinematic viscosity, ν,

of liquid petroleum products, both transparent and opaque, by measuring the time for a volume of

liquid to flow under gravity through a calibrated glass capillary viscometer. The dynamic viscosity, η,

is obtained by multiplying the measured kinematic viscosity by the density, ρ, of the liquid. The range

2 2

of kinematic viscosities covered in this test method is from 0,2 mm /s to 300 000 mm /s over the

temperature range –20 °C to +150 °C.

NOTE The result obtained from this document is dependent upon the behaviour of the sample and is intended

for application to liquids for which primarily the shear stress and shear rates are proportional (Newtonian flow

behaviour). If, however, the viscosity varies significantly with the rate of shear, different results can be obtained

from viscometers of different capillary diameters. The procedure and precision values for residual fuel oils,

which under some conditions exhibit non-Newtonian behaviour, have been included.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments) applies.

ISO 3105, Glass capillary kinematic viscometers — Specifications and operating instructions

ISO 3696:1987, Water for analytical laboratory use — Specification and test methods

ASTM E1137, Standard Specification for Industrial Platinum Resistance Thermometers

ASTM E2877, Standard Guide for Digital Contact Thermometers

ISO 4259-4, Petroleum and related products —Precision of measurement methods and results —Part 4:

Use of statistical control charts to validate ‘in-statistical-control’ status for the execution of a standard test

method in a single laboratory
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org
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oSIST prEN ISO 3104:2022
ISO/DIS 3104:2022(E)
3.1
kinematic viscosity
resistance to flow of a fluid under gravity

Note 1 to entry: For gravity flow under a given hydrostatic head, the pressure head of a liquid is proportional to

its density, ρ. For any particular viscometer, the time of flow of a fixed volume of fluid is directly proportional to

its kinematic viscosity, ν:
ν = η/ρ
where η is the dynamic viscosity coefficient.
3.2
dynamic viscosity
coefficient of dynamic viscosity
viscosity
ratio between the applied shear stress and rate of shear of a liquid

Note 1 to entry: It is a measure of the resistance to flow or deformation of a liquid.

Note 2 to entry: The term dynamic viscosity is also used in a different context to denote a frequency-dependent

quantity in which shear stress and shear rate have a sinusoidal time dependence.
3.3
density
mass per unit volume of a substance at a given temperature
4 Principle

The time is measured for a fixed volume of liquid to flow under gravity through the glass capillary

of a calibrated viscometer under a reproducible driving head and at a known and closely controlled

temperature. The kinematic viscosity is the product of the measured flow time and the calibration

constant of the viscometer.
5 Reagents and materials

5.1 Cleaning solution, strongly-oxidizing cleaning solution or alkaline cleaning solutions can be

used.

Alkaline cleaning solutions with a pH of greater than 10 are not recommended as they have been shown

to change the viscometer calibration. If these are used, then the viscometer calibration should be

verified to ensure there is no change.

5.2 Sample solvent, completely miscible a prewash with an aromatic solvent such as toluene or

heptane might be necessary to remove asphaltenic material. When cleaning capillaries inside the bath,

the boiling point of the cleaning solution shall be higher than the bath temperature.

5.3 Drying solvent, suitable and volatile at the used temperature. Filter before use. If moisture

remains, use a drying solvent miscible with water (5.4).

NOTE When cleaning capillaries inside the bath and if the bath temperature is higher than 50 °C, acetone is

not suitable.

5.4 Water, deionized or distilled, conforming to Grade 3 of ISO 3696:1987. Filter before use.

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oSIST prEN ISO 3104:2022
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5.5 Certified viscosity reference standards (CRM), with data provided by an accredited calibration

laboratory — traceable to the international agreed value of distilled water (1,003 4 mm /s at 20 °C

as specified in ISO/TR 3666) and calibrated in accordance with a standard practice for the basic

[8]

calibration of master viscometers and viscosity oils, such as in ASTM D2162. ISO 17034 specifies the

requirements for CRM producers.
6 Apparatus design and requirements

6.1 Drying tubes, consisting of a desiccant drying system, consisting of either externally mounted

drying tubes or an integrated desiccant drying system designed to remove ambient moisture from the

capillary tube. Ensure that they are packed loosely and that the desiccant is not saturated with water.

6.2 Sample filter, micron screen or fretted (sintered) glass filter, no more than 75 µm.

6.3 Reagent filter, micron screen or fretted (sintered) glass filter, no more than 11 µm.

6.4 Ultrasonic bath, unheated — with an operating frequency between 25 kHz to 60 kHz and a

typical power output of ≤100 W, of suitable dimensions to hold container(s) placed inside of bath, for

use in effectively dissipating and removing air or gas bubbles that can be entrained in viscous sample

types prior to analysis. It is permissible to use ultra-sonic baths with operating frequencies and

power outputs outside this range; however, it is the responsibility of the laboratory to conduct a data

comparison study to confirm that results determined with and without the use of such ultrasonic baths

does not materially impact results.
6.5 Manual apparatus
6.5.1 Glass capillary viscometer, calibrated in accordance with ISO 3105.

The viscometer shall have a certificate of calibration provided by an accredited laboratory that meets

ISO/IEC 17025. The calibration constant should be checked before first use of the capillary and only

changed if necessary.

The calibration constant, C, is dependent upon the gravitational acceleration at the place of calibration.

The variation in the value of g across the earth’s surface is about 0,5 % due to latitude plus approximately

0,003 % per 100 m altitude. Apply a gravity correction to the viscometer calibration constant as in

Formula (1), if the acceleration of gravity of the testing laboratory differs by more than 0,1 % of the

calibration laboratory.
CC= (1)
2 ()

where the subscripts 1 and 2 indicate, respectively, the calibration laboratory and the testing laboratory.

NOTE Calculation of acceleration of gravity values can be found at www .NPL .co .uk.

IMPORTANT — Viscometers used for silicone fluids, fluorocarbons and other liquids, which are

difficult to remove using a cleaning agent, shall be reserved for the exclusive use of those fluids,

except during their calibration. Subject such viscometers to calibration checks at frequent

intervals. The solvent washings from these viscometers shall not be used for the cleaning of

other viscometers. If the viscometer is cleaned using the material in 5.1 then the user shall

verify the calibration before further use.
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oSIST prEN ISO 3104:2022
ISO/DIS 3104:2022(E)

6.5.2 Viscometer holder or mounting device within the temperature-controlled bath, enabling

the glass viscometer to be suspended so that the upper meniscus is directly above the lower meniscus

vertically within 1° in all directions.

Those viscometers whose upper meniscus is offset from directly above the lower meniscus shall be

suspended vertically within 0,3° in all directions (see ISO 3105).

The proper alignment of vertical parts may be confirmed by using a plumb line, but for rectangular

baths with opaque ends, this might not be possible.

6.5.3 Temperature-controlled bath, containing a transparent liquid of sufficient depth such that at

no time during the measurement is any portion of the sample in the viscometer less than 20 mm below

the surface of the bath liquid or less than 20 mm above the bottom of the bath.

Temperature control of the bath liquid shall be such that, for each series of flow-time measurements,

within the range of 15 °C to 100 °C the temperature of the bath medium does not vary by more

than ±0,02 °C from the selected temperature over the length of the viscometer, and/or between

the position of each viscometer, and/or at the location of the temperature measuring device i.e. the

temperature needs to be constant at the capillary and at the position of the temperature measuring

device within a maximum difference of 0,04 °C. For temperatures outside this range, the deviation from

the desired temperature shall not exceed ±0,05 °C.

Adjust and maintain the viscometer bath at the required test temperature within the limits given

in 6.5.3, taking account of the conditions given in Annex B and of the corrections supplied on the

certificates of calibration for the temperature measuring device. Maintain the bath temperature at the

test temperature using the readings of the temperature measuring device with the corrections supplied

by the certificate of calibration.

The temperature measuring device shall be held in an upright position under the same conditions of

immersion as when calibrated.
6.5.4 Temperature-measuring device, for the range 0 °C to 100 °C, being either:

a) a calibrated liquid-in-glass thermometer, as listed in Annex B with a calibration and measurement

capability (CMC) of ±0,04 °C after correction or better, or

b) a digital contact thermometer (DCT) as described in Table 1 for this temperature with equal or

better CMC.
NOTE a DCT is preferred due to the lower uncertainty of measurment

6.5.4.1 The calibration data should be traceable to a calibration or metrology standards body and

meet the uncertainty of measurement required. The calibration certificate shall include data covering

the series of temperature test points which are appropriate for its intended use. When two temperature

measuring devices are used in the same bath in this range, they shall agree within 0,04 °C.

If calibrated liquid-in-glass thermometers are used, the use of two thermometers is recommended.

Outside the range 0 °C to 100 °C, a calibrated liquid in-glass thermometer with a CMC of ±0,1 °C or

better shall be used, and when two temperature measuring devices are used in the same bath they shall

agree within ±0,1 °C.

When using liquid-in-glass thermometers, use a magnifying device to read the thermometer to

the nearest 1/5 division (e.g. 0,01 °C or 0,02 °C) to ensure that the required test temperature and

temperature control capabilities are met. It is recommended that thermometer readings (and any

corrections supplied on the certificates of calibrations for the thermometers) be recorded on a periodic

basis to demonstrate compliance with the test method requirements.

6.5.4.2 A DCT meeting the requirements in Table 1 is to be used and is dependent upon temperature

range in use
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ISO/DIS 3104:2022(E)

NOTE The resulting uncertainty of calibration can be dependent upon the immersion depth.

6.5.4.3 The DCT probe is to be immersed no less than the immersion depth stated on the calibration

certificate.
[10]

NOTE With respect to DCT probe immersion depth, a procedure is available in ASTM E644-11, Section 7,

[9]

for determining the minimum depth. With respect to an ice bath, ASTM E563 provides guidance on the

preparation of an ice bath however variance from the specific steps is permitted provided preparation is

consistent as it is being used to track change in calibration.

6.5.4.4 The DCT probe calibration drift should be verified periodically whilst in use , and not less

than once a year. If the measurement of DCT calibration drift exceeds the specified limit, it is to be fully

recalibrated consistent with its range-of-use. If the drift exceeds the noted limit for calibration drift,

then it is to be reverified at a shorter time period, and not less than once per month .until this is noted

as stable

NOTE Procedures ASTM E563 and ASTM E644-11, provides guidance on the steps required to check

calibration drift
Table 1 — DCT requirements
Criteria Minimum requirements
DCT ASTM E2877
Display resolution 0,01 °C, recommended 0,001 °C
Display accuracy for Range : -80 °C -0 °C , 0,05 °C
combined probe and
Range : 0 °C -100 °C , 0,02 °C
sensor
Range : >100 °C, 0,05 °C
Sensor type RTD, such as a PRT or thermis
...