SIST EN ISO 2592:2017

Petroleum and related products - Determination of flash and fire points - Cleveland open cup method (ISO 2592:2017)

ISO 2592:2017 specifies a procedure for the determination of flash and fire points of petroleum products using the Cleveland open cup apparatus. It is applicable to petroleum products having open cup flash points between 79 °C and 400 °C, except fuel oils which are most commonly tested by the closed cup procedure described in ISO 2719.

Mineralölerzeugnisse und verwandte Produkte - Bestimmung des Flamm- und Brennpunktes - Verfahren mit offenem Tiegel nach Cleveland (ISO 2592:2017)

Diese Internationale Norm legt ein Verfahren zur Bestimmung des Flammpunktes und des Brenn¬punktes von Mineralölprodukten unter Verwendung einer Prüfeinrichtung mit offenem Tiegel nach Cleveland fest. Sie gilt für Mineralölprodukte, deren Flammpunkte im offenen Tiegel zwischen 79 °C und 400 °C liegen, mit Ausnahme von Heizöl, die üblicherweise nach dem Verfahren im geschlossenen Tiegel nach ISO 2719 [5] geprüft werden.

Pétrole et produits connexes - Détermination de l'éclair et de feu points - Cleveland méthode vase ouvert (ISO 2592:2017)

ISO 2592:2017 spécifié une méthode pour la détermination des points d'éclair et de feu de produits pétroliers à l'aide de l'appareil Cleveland à vase ouvert. Elle s'applique aux produits pétroliers dont les points d'éclair en vase ouvert sont compris entre 79 et 400 °C, à l'exception des huiles combustibles, qui sont généralement soumises à essai à l'aide de la méthode en vase clos décrite dans l'ISO 2719.

Nafta in sorodni proizvodi - Določevanje plamenišča in točke gorenja - Metoda z odprto posodo po Clevelandu (ISO 2592:2017)

ISO 2592:2017 določa postopek za določevanje plamenišča in točke gorenja naftnih derivatov z uporabo odprte posode po Clevelandu. Uporablja se za naftne derivate z odprtimi plamenišči med 79 °C in 400 °C, razen za gorivna olja, ki jih najpogosteje preskušajo z metodo zaprte posode, opisano v standardu ISO 2719.

General Information

• Status: Published
• Public Enquiry End Date: 04-May-2016
• Publication Date: 07-Nov-2017
• ICS: 75.080 - Petroleum products in general
• Technical Committee: NAD - Petroleum products, lubricants and related products
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 25-Oct-2017
• Due Date: 30-Dec-2017
• Completion Date: 08-Nov-2017
• Directive: 2008/68/EC - Directve 2008/68/EC of the European Parliament and of the council of 24 September 2008 on the inland transport of the dangerous goods
• Ref Project: EN ISO 2592:2017 - Petroleum and related products - Determination of flash and fire points - Cleveland open cup method (ISO 2592:2017)

Relations

• Replaces: SIST EN ISO 2592:2001 - Determination of flash and fire points - Cleveland open cup method (ISO 2592:2000)
• Effective Date: 01-Dec-2017

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 2592:2017
01-december-2017
1DGRPHãþD
SIST EN ISO 2592:2001
1DIWDLQVRURGQLSURL]YRGL'RORþHYDQMHSODPHQLãþDLQWRþNHJRUHQMD0HWRGD]
RGSUWRSRVRGRSR&OHYHODQGX,62

Petroleum and related products - Determination of flash and fire points - Cleveland open

cup method (ISO 2592:2017)
Mineralölerzeugnisse und verwandte Produkte - Bestimmung des Flamm- und
Brennpunktes - Verfahren mit offenem Tiegel nach Cleveland (ISO 2592:2017)

Pétrole et produits connexes - Détermination de l'éclair et de feu points - Cleveland

méthode vase ouvert (ISO 2592:2017)
Ta slovenski standard je istoveten z: EN ISO 2592:2017
ICS:
75.080 Naftni proizvodi na splošno Petroleum products in
general
SIST EN ISO 2592:2017 en,fr,de

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

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SIST EN ISO 2592:2017
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SIST EN ISO 2592:2017
EN ISO 2592
EUROPEAN STANDARD
NORME EUROPÉENNE
September 2017
EUROPÄISCHE NORM
ICS 75.080 Supersedes EN ISO 2592:2001
English Version
Petroleum and related products - Determination of flash
and fire points - Cleveland open cup method (ISO
2592:2017)

Pétrole et produits connexes - Détermination des Mineralölerzeugnisse und verwandte Produkte -

points d'éclair et de feu - Méthode Cleveland à vase Bestimmung des Flamm- und Brennpunktes -

ouvert (ISO 2592:2017) Verfahren mit offenem Tiegel nach Cleveland (ISO
2592:2017)
This European Standard was approved by CEN on 14 August 2017.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this

European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references

concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN

member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by

translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management

Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,

Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels

© 2017 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 2592:2017 E

worldwide for CEN national Members.
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SIST EN ISO 2592:2017
EN ISO 2592:2017 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

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SIST EN ISO 2592:2017
EN ISO 2592:2017 (E)
European foreword

This document (EN ISO 2592:2017) has been prepared by Technical Committee ISO/TC 28 "Petroleum

products and lubricants" in collaboration Technical Committee CEN/TC 19 “Gaseous and liquid fuels,

lubricants and related products of petroleum, synthetic and biological origin” the secretariat of which is

held by NEN.

This European Standard shall be given the status of a national standard, either by publication of an

identical text or by endorsement, at the latest by March 2018 and conflicting national standards shall be

withdrawn at the latest by March 2018.

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

patent rights. CEN shall not be held responsible for identifying any or all such patent rights.

This document supersedes EN ISO 2592:2001.

According to the CEN-CENELEC Internal Regulations, the national standards organizations of the

following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia,

Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France,

Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands,

Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and

the United Kingdom.
Endorsement notice

The text of ISO 2592:2017 has been approved by CEN as EN ISO 2592:2017 without any modification.

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SIST EN ISO 2592:2017
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SIST EN ISO 2592:2017
INTERNATIONAL ISO
STANDARD 2592
Third edition
2017-08
Petroleum and related products —
Determination of flash and fire points
— Cleveland open cup method
Pétrole et produits connexes — Détermination des points d’éclair et
de feu — Méthode Cleveland à vase ouvert
Reference number
ISO 2592:2017(E)
ISO 2017
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SIST EN ISO 2592:2017
ISO 2592:2017(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2017, Published in Switzerland

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form

or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior

written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of

the requester.
ISO copyright office
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. [phone]
Fax [phone]
[e-mail]
www.iso.org
ii © ISO 2017 – All rights reserved
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SIST EN ISO 2592:2017
ISO 2592:2017(E)
Contents Page

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

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

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

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

4 Principle ........................................................................................................................................................................................................................ 1

5 Chemicals and materials .............................................................................................................................................................................. 2

6 Apparatus ..................................................................................................................................................................................................................... 2

7 Preparation of apparatus ............................................................................................................................................................................ 2

7.1 Location of apparatus ....................................................................................................................................................................... 2

7.2 Cleaning the test cup .......................................................................................................................................................................... 3

7.3 Preparing the test cup ....................................................................................................................................................................... 3

7.4 Assembly of apparatus ..................................................................................................................................................................... 3

7.5 Verification of apparatus ................................................................................................................................................................ 3

8 Sampling ........................................................................................................................................................................................................................ 3

9 Sample handling ................................................................................................................................................................................................... 4

9.1 Subsampling .............................................................................................................................................................................................. 4

9.2 Samples containing undissolved water ............................................................................................................................. 4

9.3 Samples that are liquid at ambient temperature....................................................................................................... 4

9.4 Samples that are semisolid or solid at ambient temperature ........................................................................ 4

10 Procedure for determining flash point ......................................................................................................................................... 4

11 Procedure for determining fire point ............................................................................................................................................. 6

12 Calculation .................................................................................................................................................................................................................. 6

13 Expression of results ........................................................................................................................................................................................ 6

14 Precision ....................................................................................................................................................................................................................... 7

14.1 General ........................................................................................................................................................................................................... 7

14.2 Repeatability, r ....................................................................................................................................................................................... 7

14.3 Reproducibility, R ................................................................................................................................................................................ 7

15 Test report ................................................................................................................................................................................................................... 7

Annex A (normative) Cleveland open cup apparatus .......................................................................................................................... 8

Annex B (normative) Temperature measuring device specification ...............................................................................11

Annex C (informative) Verification of apparatus ..................................................................................................................................13

Annex D (informative) Prevention of surface skin formation when testing bitumens

and asphalts ...........................................................................................................................................................................................................16

Bibliography .............................................................................................................................................................................................................................18

© ISO 2017 – All rights reserved iii
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SIST EN ISO 2592:2017
ISO 2592:2017(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 on 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 the following

URL: w w w . i s o .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 2592:2000), which has been technically

revised and aligned with ASTM D92.
The main technical changes compared to the previous edition are as follows:

a) Annex D on an alternative procedure for handling skin forming products has been added;

b) the temperature measuring device requirements in Annex B has been revised;

c) the flash point reproducibility has been changed from 17 °C to 18 °C, to align with ASTM D92 on the

basis of recent precision data;

d) a procedure to determine an approximate flash point of a sample with an unknown expected flash

point has been included, to align with ASTM D92.
iv © ISO 2017 – All rights reserved
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SIST EN ISO 2592:2017
INTERNATIONAL STANDARD ISO 2592:2017(E)
Petroleum and related products — Determination of flash
and fire points — Cleveland open cup method

WARNING — The use of this document can involve hazardous materials, operations and

equipment. This document does not purport to address all of the safety problems 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 fulfil

statutory and regulatory requirements for this purpose.
1 Scope

This document specifies a procedure for the determination of flash and fire points of petroleum

products using the Cleveland open cup apparatus. It is applicable to petroleum products having open

cup flash points between 79 °C and 400 °C, except fuel oils which are most commonly tested by the

closed cup procedure described in ISO 2719.
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 3170, Petroleum liquids — Manual sampling
ISO 3171, Petroleum liquids — Automatic pipeline sampling
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:

— IEC Electropedia: available at http:// www .electropedia .org/
— ISO Online browsing platform: available at http:// www .iso .org/ obp
3.1
flash point

lowest temperature of the test portion, corrected to a standard atmospheric pressure of 101,3 kPa, at

which application of a test flame causes the vapour of the test portion to ignite under the specified

conditions of test
Note 1 to entry: See 10.10.
3.2
fire point

lowest temperature of the test portion, corrected to a barometric pressure of 101,3 kPa, at which

application of a test flame causes the vapour of the test portion to ignite and sustain burning for a

minimum of 5 s under the specified conditions of test
4 Principle

The test cup is filled to a specified level with the test portion. The temperature of the test portion may

be increased rapidly (5 °C/min to 17 °C/min) at first and then at a slow constant rate (5 °C/min to

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SIST EN ISO 2592:2017
ISO 2592:2017(E)

6 °C/min) as the flash point is approached. At specified temperature intervals, a small test flame is

passed across the test cup.

The lowest temperature at which application of the test flame causes the vapour above the surface of the

liquid to ignite is taken as the flash point at ambient barometric pressure. To determine the fire point,

the test is continued until the application of the test flame causes the vapour above the test portion to

ignite and burn for at least 5 s. The flash point and fire point obtained at ambient barometric pressure

are corrected to standard atmospheric pressure using a formula.
5 Chemicals and materials

5.1 Cleaning solvent, for removal of traces of sample from the test cup and cover.

The choice of solvent depends upon the previous material tested and the tenacity of the residue. Low

volatility aromatic (benzene-free) solvents may be used to remove traces of oil, and mixed solvents can

be efficacious for the removal of gum type deposits.

5.2 Verification liquids, certified reference material (CRM) or secondary working standards (SWS)

(see, for instance, C.2).

5.3 Steel wool, any grade capable of removing carbon deposits without damage to the test cup.

6 Apparatus
6.1 Cleveland open cup apparatus, as specified in Annex A.

If automated equipment is used, ensure that it has been established that the results obtained are

within the precision of this document, that the test cup and test flame applicator conform to the

key dimensional and mechanical requirements specified in Annex A and the procedures described

in Clauses 7, 10 and 11 are followed. If automated testers are used, the user shall ensure that all the

manufacturer’s instructions for adjusting and operating the instrument are followed.

In cases of dispute, the flash point as determined manually shall be considered the referee test.

6.2 Shield, to cover at least three sides of the test cup.
The apparatus may include a built-in draught shield.

6.3 Temperature measuring device, which shall meet the requirements for accuracy and have the

response as specified in Annex B.

6.4 Barometer, reading absolute pressure accurate to 0,5 kPa with a resolution of 0,1 kPa.

Barometers precorrected to give sea level readings, such as those used at weather stations and airports,

shall not be used.
7 Preparation of apparatus
7.1 Location of apparatus

Place the apparatus (6.1) on a level and steady surface in a draught-free room (see below). Shield the top

of the manual apparatus from strong light by any suitable means to permit detection of the flash point.

When draughts cannot be avoided, it is recommended good practice to surround the apparatus with

a shield.
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SIST EN ISO 2592:2017
ISO 2592:2017(E)

When testing samples which produce toxic vapours, the apparatus may be located in a fume hood with

an individual control of air flow, adjusted so that vapours are withdrawn without causing air currents

over the test cup.
7.2 Cleaning the test cup

Wash the test cup with an appropriate solvent (5.1) to remove any traces of gum or residue remaining

from a previous test. Dry the test cup using a stream of clean air to ensure complete removal of the

solvent used. If any deposits of carbon are present, remove them by rubbing with steel wool (5.3).

7.3 Preparing the test cup

7.3.1 If the alternative procedure referred to in 10.1 is used, follow the instructions in Annex D.

7.3.2 Before use, cool the test cup to at least 56 °C below the expected flash point.

7.4 Assembly of apparatus

Support the liquid in glass thermometer in a vertical position with the bottom of the bulb (6,4 ± 0,5) mm

from the bottom of the test cup, and located at a point halfway between the centre and side of the test

cup on a diameter perpendicular to the arc (or line) of the sweep of the test flame, and on the side

opposite to the test flame applicator. It is not necessary to restrict electronic temperature measuring

devices to be mounted vertically, provided their performance is in accordance with the requirements in

the test method.

The vertical position of the temperature measuring device may be set by lowering until it contacts the

bottom of the test cup, and then raise it by (6,4 ± 0,5) mm.
7.5 Verification of apparatus

7.5.1 Verify the correct functioning of the apparatus at least once a year by testing a certified reference

material (CRM) (5.2). The result obtained shall be equal to or less than R/√2 from the certified value of

the CRM, where R is the reproducibility of the method (see Clause 14).

It is recommended practice during verification of an automated apparatus to visually observe the

detected flash point for correct operation.

It is recommended that more frequent verification checks are made using secondary working standards

(SWSs) (5.2) or other verification materials with a proven value.

A recommended procedure for apparatus verification using CRMs and SWSs, and the production of

SWSs, is given in Annex C.

7.5.2 The numerical values obtained during the verification check shall not be used to provide a bias

statement, nor shall they be used to make any correction to the flash points subsequently determined

using the apparatus.

7.5.3 It is good practice to select a CRM or SWS that has a certified value similar to the flash point of

products being tested.
8 Sampling

8.1 Unless otherwise specified, obtain samples for analysis in accordance with the procedures given in

ISO 3170, ISO 3171 or an equivalent national standard.
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SIST EN ISO 2592:2017
ISO 2592:2017(E)

8.2 Place samples in tightly sealed containers, appropriate to the material being sampled, and for

safety purposes, ensure that the sample container is only filled 85 % to 95 % of its capacity.

8.3 Store the samples in conditions to minimize vapour loss and pressure build up. Avoid storing the

samples at temperatures in excess of 30 °C.
9 Sample handling
9.1 Subsampling

Subsample at a temperature at least 56 °C below the expected flash point. If an aliquot of the original

sample is to be stored prior to testing, ensure that the container is filled to more than 50 % of its

capacity.

NOTE The results of flash point determinations can be affected if the sample volume falls below 50 % of the

container capacity.
9.2 Samples containing undissolved water

Flash point results can be affected by the presence of water; if a sample contains undissolved water,

decant a water-free aliquot prior to mixing.

NOTE Flash and fire point results can be affected by the presence of water, and splashing can occur.

9.3 Samples that are liquid at ambient temperature

Mix samples by gently shaking by hand prior to the removal of the test portion, taking care to minimize

the loss of volatile components, and proceed in accordance with Clause 10.
9.4 Samples that are semisolid or solid at ambient temperature

Heat the sample in its container in a heating bath or oven at a temperature not exceeding 56 °C below

the expected flash point. Ensure that high pressures do not develop in the container. Avoid overheating

the sample as this could lead to the loss of volatile components. After gentle agitation, proceed in

accordance with Clause 10.
10 Procedure for determining flash point

10.1 Samples that can form a skin during testing may be tested by removing the skin formed as described

in 10.6 to 10.8.1. An alternative procedure is given in Annex D.

10.2 Record the absolute barometric pressure using a barometer (6.4) in the vicinity of the apparatus at

the time of test.

NOTE It is not considered necessary to correct the barometric pressure reading to 0 °C, although some

barometers are designed to make this correction automatically.

10.3 Fill the test cup at ambient or elevated temperature (see 9.4) so that the top of the meniscus is level

with the filling mark. Position the test cup on the centre of the heating plate. If too much sample has been

added to the test cup, remove the excess using a pipette or other suitable device; however, if there is any

sample on the outside of the apparatus, empty, clean and refill it. Destroy or remove any air bubbles or

foam on the surface of the sample while maintaining the correct level of test portion in the test cup. If

foam persists in the final stages of the test, discard the result.
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SIST EN ISO 2592:2017
ISO 2592:2017(E)
10.4 Light the test flame and adjust it to a diameter between 3,2 mm and 4,8 mm.

As a safety practice, it is strongly advised, when using automated or a manual apparatus, before heating

the test cup and test portion, to pass the test flame across the test portion in the test cup to check for

the presence of unexpected volatile material. Thereafter, it is recommended to test for a flash every

10 °C until the test portion is within 56 °C of the expected flash point.

10.5 Apply heat initially so that the rate of temperature rise of the test portion is 5 °C/min to 17 °C/min.

When the test portion temperature is approximately 56 °C below the expected flash point, decrease the

heat so that the rate of temperature rise for the last 28 °C before the expected flash point is 5 °C/min to

6 °C/min.

10.6 Avoid disturbing the vapours in the test cup by careless movements or breathing near the test cup

(see 7.1).

10.7 Apply the test flame when the temperature of the test portion is 28 °C below the expected flash

point. The test flame is applied in one direction with a smooth continuous motion, taking (1 ± 0,1) s,

to pass across the centre of the test cup, at right angles to the diameter which passes through the

thermometer, either in a straight line or along the circumference of a circle having a radius of at least

150 mm. The centre of the test flame shall move in a horizontal plane not more than 2 mm above the

plane of the upper edge of the test cup. For the next test flame application, pass the flame in the opposite

direction.
NOTE Some automated apparatus pass the test flame in one single direction.

10.8 If a flash is detected on this application of the test flame or during a preliminary application (see

10.4), discontinue the test and repeat the test using a fresh test portion with an expected flash point of at

least 28 °C below the previous test value.

10.8.1 If a skin forms over the test portion, carefully move it aside with a spatula or comb and continue

the determination.

10.8.2 If a flash has not been detected, continue applying the test flame each time thereafter at a

temperature reading that is a multiple of 2 °C.

NOTE Higher flash points have been detected when skins formed on the surfaces of test portions have not

been removed.

10.9 When testing a sample whose expected flash point temperature is not known, bring the test portion

in the test cup to a temperature no greater than 50 °C, or if the sample required heating to be transferred

into the test cup, bring the test portion in the test cup to that temperature. Apply the test flame, in the

manner described in 10.7, beginning at least 5 °C above the starting temperature. Continue heating the

test specimen at
...