FprEN ISO 8501-4

SLOVENSKI STANDARD
oSIST prEN ISO 8501-4:2019
01-junij-2019
Priprava jeklenih podlag pred nanašanjem barvnih in sorodnih premazov -

Vizualno ocenjevanje čistosti površine - 4. del: Začetno stanje površine, stopnje

Preparation of steel substrates before application of paints and related products - Visual

assessment of surface cleanliness - Part 4: Initial surface conditions, preparation grades

and flash rust grades in connection with high-pressure water jetting (ISO/DIS 8501-

Préparation des subjectiles d'acier avant application de peintures et de produits

assimilés - Évaluation visuelle de la propreté d'un subjectile - Partie 4: États de surface

initiaux, degrés de préparation et degrés de fleurette de rouille après décapage à l'eau

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

Préparation des subjectiles d'acier avant application de peintures et de produits assimilés — Évaluation

Partie 4: États de surface initiaux, degrés de préparation et degrés de fleurette de rouille après décapage à

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

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

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

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

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

4 Initial surface conditions ............................................................................................................................................................................. 2

5 Preparation grades ............................................................................................................................................................................................ 3

6 Flash rust grades .................................................................................................................................................................................................. 4

7 Procedure for the visual assessment of steel substrates ............................................................................................ 4

8 Photographs .............................................................................................................................................................................................................. 5

Annex A (informative) Guidance on cleaning with water ............................................................................................................... 7

Bibliography ................................................................................................................................................................................................................................ 9

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

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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

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

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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.

This second edition cancels and replaces the first edition (ISO 8501-4:2006), which has been technically

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

b) the presence of surface contaminants, including salts, dust, oils and greases;

International standards ISO 8501, ISO 8502 and ISO 8503 have been prepared to provide methods of

assessing these factors, while ISO 4628-3 provides guidance on evaluating the degradation of paint

ISO 8501, ISO 8502 and ISO 8503 do not contain recommendations for the protective systems to be

applied to the steel surface. Neither do they contain recommendations for the preparation grades 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 will be necessary for the users of these International

— compatible and appropriate both for the environmental conditions to which the steel will be exposed

ISO 8501, ISO 8502 and ISO 8503 deal with aspects of preparation of steel substrates under the general

heading Preparation of steel substrates before application of paints and related products. They have

— ISO 8503 — Surface roughness characteristics of blast-cleaned steel substrates.

Each of these International Standards is in turn divided into separate parts. This part of ISO 8501

— five initial surface conditions, three of them applicable to degraded paint coatings and two of them

— four preparation grades for each initial surface condition, after partial or full removal of previous

This part of ISO 8501 is intended to be a tool for the visual assessment of initial surface conditions,

preparation grades and flash rust grades in connection with high-pressure water jetting. It includes 28

The photographs showing the five initial surface conditions and each preparation grade are reproduced

by permission of Hempel A/S. The photographs representing each of the three flash rust grades are

NOTE This part of ISO 8501 contains the text in two of the three official languages of ISO, English and French.

This part of ISO 8501 specifies a series of preparation grades for steel surfaces after removal/partial

removal of water-soluble contaminants, rust, previous paint coatings and other foreign matter by

high-pressure water jetting. The various grades are defined by written descriptions together with

photographs that are representative examples within the tolerances for each grade as described in

words. In addition, this part of ISO 8501 specifies both initial surface conditions and after-cleaning flash

rust grades, also defined by written descriptions together with representative photographic examples.

NOTE 1 Examples of foreign matter, other than paint residues, are salt, grime, dirt, mill scale, oil, grease and

This part of ISO 8501 relates the cleanliness of the surface to its visual appearance. In many instances,

this is sufficient for the purpose but, for coatings likely to be exposed to severe environments, such as

water immersion and continuous condensation conditions, consideration should be given to testing for

soluble salts and other invisible contaminants on the visually clean surface by the physical and chemical

The roughness characteristics of the surface should also be considered by reference to ISO 8503,

although it must be noted that preparation by high- pressure water jetting does not create a profile or

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 4628-3, Paints and varnishes — Evaluation of degradation of coatings — Designation of quantity and

size of defects, and of intensity of uniform changes in appearance — Part 3: Assessment of degree of rusting

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

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