EN ISO 4628-2:2016
(Main)Paints and varnishes - Evaluation of degradation of coatings - Designation of quantity and size of defects, and of intensity of uniform changes in appearance - Part 2: Assessment of degree of blistering (ISO 4628-2:2016)
General Information
- Abstract
ISO 4628-2:2016 specifies a method for assessing the degree of blistering of coatings by comparison with pictorial standards.
The pictorial standards provided in this part of ISO 4628 illustrate blisters in the sizes 2, 3, 4, and 5, and each size in the quantities (densities) 2, 3, 4, and 5.
ISO 4628‑1 defines the system used for designating the quantity and size of defects and the intensity of changes in appearance of coatings and outlines the general principles of the system. This system is intended to be used, in particular, for defects caused by ageing and weathering, and for uniform changes such as colour changes, for example yellowing.
- Status
- Published
- Publication Date
- 09-Feb-2016
- Withdrawal Date
- 09-Aug-2016
- Technical Committee
- CEN/TC 139 - Paints and varnishes
- Drafting Committee
- CEN/TC 139 - Paints and varnishes
- Current Stage
- 6060 - Definitive text made available (DAV) - Publishing
- Start Date
- 10-Feb-2016
- Completion Date
- 10-Feb-2016
Overview
EN ISO 4628-2:2016 (ISO 4628-2:2016) is a standardized method for assessing the degree of blistering in paints and varnishes. The standard specifies visual assessment by comparison with pictorial standards that illustrate blister sizes (S2–S5) and quantities (densities 2–5). It is part of the ISO 4628 series for evaluation of coating degradation and is intended for defects produced by ageing and weathering.
Key topics and requirements
- Assessment method: Compare the coating surface with the pictorial standards (Figures and calibration images) to determine blister size and quantity (density). Typical results are reported in the format degree (size), for example 2(S2).
- Pictorial standards: Illustrations are provided for blister sizes 2, 3, 4, 5, each shown at densities 2, 3, 4, 5. A very small blister size (S1) is noted as not visible to normal corrected vision and requires ×10 magnification.
- Lighting and viewing: Assessments must be carried out under suitable illumination as specified by ISO 13076 (normative reference).
- Optical imaging: If an optical imaging system is used, it must be calibrated against the images in Annex A (calibration images).
- Reporting: The test report shall include coating identification, reference to ISO 4628‑2, surface details and location, the blistering rating and affected area (percentage), illumination conditions, anomalies, and date of examination.
- Correlation guidance: Annex B provides information correlating ISO 4628-2 ratings with ASTM D714 blistering ratings, aiding cross-standard comparisons.
Practical applications and users
- Quality control teams in paint and varnish manufacturing for batch acceptance and consistency checks.
- Independent coating test laboratories performing standardized assessments for contracts and certification.
- Specifiers, architects, and asset owners evaluating coating condition on structures subject to weathering (buildings, bridges, marine structures).
- Failure analysis and R&D groups investigating causes of blistering and improving coating formulations.
- Contract inspectors and maintenance planners who need repeatable, comparable records of coating degradation.
Related standards
- ISO 4628-1 - General introduction and designation system for quantity, size and intensity ratings.
- ISO 13076 - Lighting and procedure for visual assessments of coatings (normative for illumination).
- ASTM D714 - Common U.S. standard for blistering; Annex B offers correlation guidance.
Keywords: ISO 4628-2, degree of blistering, paints and varnishes, coating evaluation, pictorial standards, coating defects, ASTM D714, optical imaging calibration.
Relations
- Effective Date
- 16-Apr-2014
- Refers
ISO 13076:2012 - Paints and varnishes — Lighting and procedure for visual assessments of coatings - Effective Date
- 09-Feb-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Referred By
EN 13523-26:2006 - Coil coated metals - Test methods - Part 26: Resistance to condensation of water - Effective Date
- 28-Jan-2026
- Referred By
EN 13523-8:2017 - Coil coated metals - Test methods - Part 8: Resistance to salt spray (fog) - Effective Date
- 28-Jan-2026
- Referred By
EN 13523-21:2017 - Coil coated metals - Test methods - Part 21: Evaluation of outdoor exposed panels - Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Referred By
EN 13523-26:2014 - Coil coated metals - Test methods - Part 26: Resistance to condensation of water - Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Referred By
EN 13523-21:2010 - Coil coated metals - Test methods - Part 21: Evaluation of outdoor exposed panels - Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
Frequently Asked Questions
EN ISO 4628-2:2016 is a standard published by the European Committee for Standardization (CEN). Its full title is "Paints and varnishes - Evaluation of degradation of coatings - Designation of quantity and size of defects, and of intensity of uniform changes in appearance - Part 2: Assessment of degree of blistering (ISO 4628-2:2016)". This standard covers: ISO 4628-2:2016 specifies a method for assessing the degree of blistering of coatings by comparison with pictorial standards. The pictorial standards provided in this part of ISO 4628 illustrate blisters in the sizes 2, 3, 4, and 5, and each size in the quantities (densities) 2, 3, 4, and 5. ISO 4628‑1 defines the system used for designating the quantity and size of defects and the intensity of changes in appearance of coatings and outlines the general principles of the system. This system is intended to be used, in particular, for defects caused by ageing and weathering, and for uniform changes such as colour changes, for example yellowing.
ISO 4628-2:2016 specifies a method for assessing the degree of blistering of coatings by comparison with pictorial standards. The pictorial standards provided in this part of ISO 4628 illustrate blisters in the sizes 2, 3, 4, and 5, and each size in the quantities (densities) 2, 3, 4, and 5. ISO 4628‑1 defines the system used for designating the quantity and size of defects and the intensity of changes in appearance of coatings and outlines the general principles of the system. This system is intended to be used, in particular, for defects caused by ageing and weathering, and for uniform changes such as colour changes, for example yellowing.
EN ISO 4628-2:2016 is classified under the following ICS (International Classification for Standards) categories: 87.040 - Paints and varnishes. The ICS classification helps identify the subject area and facilitates finding related standards.
EN ISO 4628-2:2016 has the following relationships with other standards: It is inter standard links to EN ISO 4628-2:2003, ISO 13076:2012, EN 438-2:2016, EN 13523-25:2022, EN 4687:2012, EN 13523-26:2006, EN 13523-8:2017, EN 13523-21:2017, EN 4687:2021, EN ISO 105-B10:2011, EN 13523-26:2014, EN ISO 16474-1:2013, EN 13523-21:2010, EN 17526:2021+A1:2025, EN 13500:2003. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
EN ISO 4628-2:2016 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
SLOVENSKI STANDARD
01-april-2016
1DGRPHãþD
SIST EN ISO 4628-2:2004
Barve in laki - Ovrednotenje propadanja premazov - Ugotavljanje obsega in
velikosti poškodb ter intenzitete enakomernih sprememb videza - 2. del:
Ocenjevanje stopnje mehurjenja (ISO 4628-2:2016)
Paints and varnishes - Evaluation of degradation of coatings - Designation of quantity
and size of defects, and of intensity of uniform changes in appearance - Part 2:
Assessment of degree of blistering (ISO 4628-2:2016)
Beschichtungsstoffe - Beurteilung von Beschichtungsschäden - Bewertung der Menge
und der Größe von Schäden und der Intensität von gleichmäßigen Veränderungen im
Aussehen - Teil 2: Bewertung des Blasengrades (ISO 4628-2:2016)
Peintures et vernis - Évaluation de la dégradation des revêtements - Désignation de la
quantité et de la dimension des défauts, et de l'intensité des changements uniformes
d'aspect - Partie 2: Évaluation du degré de cloquage (ISO 4628-2:2016)
Ta slovenski standard je istoveten z: EN ISO 4628-2:2016
ICS:
87.040 Barve in laki Paints and varnishes
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EN ISO 4628-2
EUROPEAN STANDARD
NORME EUROPÉENNE
February 2016
EUROPÄISCHE NORM
ICS 87.040 Supersedes EN ISO 4628-2:2003
English Version
Paints and varnishes - Evaluation of degradation of
coatings - Designation of quantity and size of defects, and
of intensity of uniform changes in appearance - Part 2:
Assessment of degree of blistering (ISO 4628-2:2016)
Peintures et vernis - Évaluation de la dégradation des Beschichtungsstoffe - Beurteilung von
revêtements - Désignation de la quantité et de la Beschichtungsschäden - Bewertung der Menge und der
dimension des défauts, et de l'intensité des Größe von Schäden und der Intensität von
changements uniformes d'aspect - Partie 2: Évaluation gleichmäßigen Veränderungen im Aussehen - Teil 2:
du degré de cloquage (ISO 4628-2:2016) Bewertung des Blasengrades (ISO 4628-2:2016)
This European Standard was approved by CEN on 19 December 2015.
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, 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
© 2016 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 4628-2:2016 E
worldwide for CEN national Members.
Contents Page
European foreword . 3
European foreword
This document (EN ISO 4628-2:2016) has been prepared by Technical Committee ISO/TC 35 "Paints
and varnishes" in collaboration with Technical Committee CEN/TC 139 “Paints and varnishes” the
secretariat of which is held by DIN.
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 August 2016, and conflicting national standards shall
be withdrawn at the latest by August 2016.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent
rights.
This document supersedes EN ISO 4628-2:2003.
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, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Endorsement notice
The text of ISO 4628-2:2016 has been approved by CEN as EN ISO 4628-2:2016 without any
modification.
INTERNATIONAL ISO
STANDARD 4628-2
Third edition
2016-01-15
Paints and varnishes — Evaluation
of degradation of coatings —
Designation of quantity and size of
defects, and of intensity of uniform
changes in appearance —
Part 2:
Assessment of degree of blistering
Peintures et vernis — Évaluation de la dégradation des revêtements
— Désignation de la quantité et de la dimension des défauts, et de
l’intensité des changements uniformes d’aspect —
Partie 2: Évaluation du degré de cloquage
Reference number
ISO 4628-2:2016(E)
©
ISO 2016
ISO 4628-2:2016(E)
© ISO 2016, Published in Switzerland
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ii © ISO 2016 – All rights reserved
ISO 4628-2:2016(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Assessment . 1
5 Expression of results . 2
6 Test report . 2
Annex A (normative) Calibration images . 7
Annex B (informative) Correlation between ISO 4628-2 and ASTM D 714 rating systems .12
Bibliography .13
ISO 4628-2:2016(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 w
...