ISO 8502-15:2020

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 8502-15
ISO/TC 35/SC 12
Preparation of steel substrates before
Secretariat: BSI
application of paints and related
Voting begins on:
2020-05-20 products — Tests for the assessment
of surface cleanliness —
Voting terminates on:
2020-07-15
Part 15:
Extraction of soluble contaminants for
analysis by acid extraction
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 SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 8502-15:2020(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
©
NATIONAL REGULATIONS. ISO 2020

---------------------- Page: 1 ----------------------
ISO/FDIS 8502-15:2020(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2020
All rights reserved. Unless otherwise specified, or required in the context of its implementation, 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
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved

---------------------- Page: 2 ----------------------
ISO/FDIS 8502-15:2020(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Apparatus and materials. 2
5.1 Adhesive cell. 2
5.2 Reusable syringe. 2
5.3 Solvent . 2
5.4 Contact thermometer . 3
6 Procedure. 3
6.1 Selection of test surface . 3
6.2 Extraction by patch or sleeve by injection . 3
6.3 Extraction by sleeve by pre-filling . 4
6.4 Blank test . 4
7 Analysis . 4
8 Test report . 5
Annex A (normative) Leak test for type testing of adhesive cells (patches and sleeves) .8
Bibliography .10
© ISO 2020 – All rights reserved iii

---------------------- Page: 3 ----------------------
ISO/FDIS 8502-15:2020(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 35, Paints and varnishes, Subcommittee
SC 12, Preparation of steel substrates before application of paints and related products.
A list of all parts in the ISO 8502 series can be found on the ISO website.
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.
iv © ISO 2020 – All rights reserved

---------------------- Page: 4 ----------------------
ISO/FDIS 8502-15:2020(E)

Introduction
The performance of protective coatings of paint and related products applied to steel is significantly
affected by the state of the steel surface immediately prior to painting. The principal factors that are
known to influence this performance are:
a) the presence of rust and mill scale;
b) the presence of surface contaminants, including salts, dust, oils and greases;
c) the surface profile.
The ISO 8501, ISO 8502 and ISO 8503 series have been prepared to provide methods of assessing these
factors, while the ISO 8504 series provides guidance on the preparation methods that are available for
cleaning steel substrates, indicating the capabilities of each in attaining specified levels of cleanliness.
These international standards do not contain recommendations for the protective coating systems
to be applied to the steel surface. Neither do they contain recommendations for the surface quality
requirements for specific situations, even though surface quality can have a direct influence on the
choice of protective coating to be applied and on its performance. Such recommendations are found in
other documents such as national standards and codes of practice. It is necessary for the users of these
international standards to ensure that the qualities specified are:
— compatible and appropriate both for the environmental conditions to which the steel will be exposed
and for the protective coating system to be used;
— within the capability of the cleaning procedure specified.
The four series of international standards referred to above deal with the following aspects of
preparation of steel substrates:
— visual assessment of surface cleanliness (see ISO 8501);
— tests for the assessment of surface cleanliness (see ISO 8502);
— surface roughness characteristics of blast-cleaned steel substrates (see ISO 8503);
— surface preparation methods (see ISO 8504).
Each of these series of international standards is in turn divided into separate parts.
This document, along with the other parts of the ISO 8502 series, specifies tests for the assessment
of surface cleanliness. In connection with such tests, there are several methods for the extraction,
for analysis, of soluble contaminants on surfaces to be painted. Some of these methods are based
on the swabbing of comparatively large test surfaces. This technique provides average values of the
contamination present, but it might conceal localized concentrations of contaminants. Swabbing might
not ensure sufficient penetration to dissolve all of the deep-seated contamination such as ferrous salts.
Furthermore, the solvent used affects the dissolution rate and what contaminants are dissolved. This
document covers sampling with a weak acid as solvent.
There are other methods, however, which use small cells for the liquid to remove and collect the surface
contaminants. The cells (rigid or flexible) are attached to test surfaces where soluble contaminants
could be expected, for example where pitting has occurred. This technique usually provides more
accurate point values of the contamination present.
© ISO 2020 – All rights reserved v

---------------------- Page: 5 ----------------------
FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 8502-15:2020(E)
Preparation of steel substrates before application of paints
and related products — Tests for the assessment of surface
cleanliness —
Part 15:
Extraction of soluble contaminants for analysis by acid
extraction
1 Scope
This document specifies a method of extracting, for analysis, acid soluble contaminants from a
surface by use of flexible cells in the form of adhesive patches or sleeves which can be attached to any
surface, regardless of its shape (flat or curved) and its orientation (facing in any direction, including
downwards).
The described method is suitable for use in the field to determine the presence of acid soluble
contaminants before painting or a similar treatment.
This document does not cover the subsequent analysis of the contaminants that have been dissolved
off. Methods of analysis suitable for field use are described in other parts of ISO 8502-5.
This document is similar in procedure to, but not equal to, ISO 8502-6. The main difference is the solvent
used and the subsequent analysis that can be performed on the extraction solution.
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 554, Standard atmospheres for conditioning and/or testing — Specifications
ISO 8501-1, Preparation of steel substrates before application of paints and related products — Visual
assessment of surface cleanliness — Part 1: Rust grades and preparation grades of uncoated steel substrates
and of steel substrates after overall removal of previous coatings
ISO 8503-2, Preparation of steel substrates before application of paints and related products — Surface
roughness characteristics of blast-cleaned steel substrates — Part 2: Method for the grading of surface
profile of abrasive blast-cleaned steel — Comparator procedure
ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories
3 Terms and definitions
No terms and definitions are listed in this document.
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/
© ISO 2020 – All rights reserved 1

---------------------- Page: 6 ----------------------
ISO/FDIS 8502-15:2020(E)

4 Principle
This document covers two types cells, adhesive patch and flexible sleeve. With the first type, an adhesive
patch with a central compartment designed to hold a weak acid is attached to the surface from which
acid soluble contaminants are to be removed. The acid is injected into the compartment by means of a
syringe, and then sucked back into the syringe. This operation is repeated and the acid left to dissolve
salts on the surface. With the second type of cell, a sleeve containing acid is attached to the surface
and the acid is left, under some agitation, to dissolve the salts. The acid now containing con
...