ISO 8504-1:1992

INTERNATIONAL
ISO
STANDARD 8504-1
First edition
1992-12-01
Preparation of steel Substrates before
application of paints and related
products - Surface preparation
methods -
Part 1:
General principles
Preparation des subjectiles d ’acier avant application de peintures et de
produits assi.mil& - Methodes de prgparation des subjectiles -
Partie 1: Principes g&Graux
Reference number
ISO 8504-1 :1992(E)

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ISO 8504=1:1992(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. Esch 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
(1 EC) on all matters of electrotechnical standardization.
Draft International Standards adopted by the technical committees are
circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting
a vote.
International Standard ISO 8504-1 was prepared by Technical Committee
ISO/rC 35, Paints and varnishes, Sub-Committee SC 12, Preparation of
steel substra tes before application of paints and related products.
ISO 8504 consists of the following Parts, under the general title Prepara-
tion of steel Substrates before application of paints and related
products - Surface prepara tion me thods:
- Part 1: General principles
- Part 2: Abrasive blast-cleaning
- Part 3: Hand- and power-tool cleaning
Further Parts are planned.
c3 ISO 1992
All rights reserved. No part of this publication may be reproduced or utilized in any form or
by any means, electronie or mechanical, including photocopying and microfilm, without per-
mission in writing from the publisher.
International Organization for Standardization
Case Postale 56 l CH-l 211 Geneve 20 l Switzerland
Printed in Switzerland
ii

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ISO 8504=1:1992(E)
Introduction
The Performance of protective coatings of paint and related products ap-
plied to steel is significantly affected by the state of the steel surface im-
mediately 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.
International Standards ISO 8501, ISO 8502 and ISO 8503 have been
prepared to provide methods of assessing these factors, while ISO 8504
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 tan 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. lt will be 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 International Standards referred to above deal with the following
aspects of preparation of steel Substrates:
ISO 8501 - Visual assessment of surface cleanliness;
ISO 8502 - Tests for the assessment of surface cleanliness;
ISO 8503 - Surface roughness characteristics of blast-cleaned steel
Substrates;
ISO 8564 - Surface prepara tion me thods.
Esch of these International Standards is in turn divided into separate Parts.
The primary objective of surface preparation is to ensure the removal of
deleterious matter and to obtain a surface that permits satisfactory ad-
. . .
Ill

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ISO 8504=1:1992(E)
hesion of the priming paint to the steel. It should also assist in reducing
the amounts of contaminants that initiate corrosion.
This part of ISO 8504 describes the general principles for the selection of
surface preparation methods. lt should be read in conjunction with
ISO 8504-2 and subsequent Parts of ISO 8504 that describe particular
surface preparation methods.
It is stressed that there is a very wide Variation in the condition of steel
surfaces requiring cleaning Prior to painting. This particularly applies to
maintenance of an already coated structure. The age of the structure and
its location, the quality of the previous surface, the Performance of the
existing coating System and the extent of breakdown, the type and inten-
sity of previous and future corrosion environments, and the intended new
coating System all influence the amount of treatment required.

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INTERNATIONAL STANDARD
ISO 8504-1: 1992( E)
Preparation of steel Substrates before application of
paints and related products
- Surface preparation
methods -
Part 1:
General principles
ISO 4628-4: 1982, Paints and varnishes - Evaluation
1 Scope
of degrada tion of pain t coatings - Designation of in-
tensity, quantity and size of common types of defect
This part of ISO 8504 describes the general principles
- Part 4: Designation of degree of cracking.
for the selection of methods for the preparation of
steel surfaces before coating with paints and related
ISO 4628-5: 1982, Paints and varnishes - Evaluation
products. lt also contains information on features that
of degradation of paint coatings - Designation of in-
must be taken into account before certain surface
tensity, quantity and size of common types of defect
preparation methods and preparation grades are
- Part 5: Designation of degree of flaking.
selected and specified.
ISO 8501-1:1988, Preparation of steel Substrates be-
fore application o f pain ts and rela ted products - Vis-
ual assessment of surface cleanliness - Part 1: Rust
2 Normative references
grades and preparation grades of uncoated steel sub-
strates and of steel Substrates after Overall removal
The following Standards contain provisions which,
0 f previous cos tings.
through reference in this text, constitute provisions
of this part of ISO 8504. At the time of publication, the
ISO 8501-2: --J, Prepara tion of steel substra tes before
editions indicated were valid. All Standards are subject
application of paints and related products - Visual
to revision, and Parties to agreements based on this
assessment of surface cleanliness - Part 2: Prepa-
part of ISO 8504 are encouraged to investigate the
ration grades of previously coated steel Substrates
possibility of applying the most recent editions of the
after localized removal of previous coatings.
Standards indicated below. Members of IEC and ISO
maintain registers of currently valid International
ISO/TR 8502-1:1991, Preparation of steel Substrates
Standards.
before application of paints and related products -
Tests for the assessment of surface cleanliness -
ISO 4628-2:1982, Paints and varnishes - Evaluation
Part 1: Field test for soluble iron corrosion products.
of degradation of paint coatings - Designation of in-
tensity, quantity and size of common types of defect
ISO 8502-2:1992, Preparation of steel Substrates be-
- Part 2: Designa tion of degree of blistering.
fore applica tion of paints and rela ted products -
Tests for the assessment of surface cleanliness -
ISO 4628-3: 1982, Paints and varnishes - Evaluation
Part 2: Laboratory determination of chloride on
of degrada tion of pain t coatings - Designa tion of in-
cleaned surfaces.
tensity, quantity and size of common types of defect
- Part 3: Designation of degree of rusting.
1) To be published.
1

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ISO 8504=1:1992(E)
ISO 8502-3:1992, Preparation of steel Substrates be- Firms carrying out surface preparation work should
fore application of pain ts and rela ted products - have the personnel and technical knowledge of the
Tests for the assessment of surface cleanliness - processes involved to enable them to carry out the
Part 3: Assessment of dust on steel surfaces pre- work adequately. All relevant health and safety regu-
pared for pain ting (pressure-sensitive tape me thod). lations shall be observed. The surfaces to be treated
should preferably be readily accessible and sufficiently
ISO 8502-4: -l) Preparation of steel Substrates before illuminated. All surface preparation work should be
applica tion o f paint and rela ted products - Tests for properly supervised and inspected.
the assessment of surface cleanliness - Part 4:
Details regarding the preliminary treatment of welds,
Guidance on the estimation of the probability of
the removal of weld spatter and removal of burrs and
condensa tion Prior to p
...