SIST EN ISO 9227:2006
(Main)Corrosion tests in artificial atmospheres - Salt spray tests (ISO 9227:2006)
Corrosion tests in artificial atmospheres - Salt spray tests (ISO 9227:2006)
This International Standard specifies the apparatus, the reagents and the procedure to be used in conducting the neutral salt spray (NSS), acetic acid salt spray (AASS) and copper-accelerated acetic acid salt spray (CASS) tests for assessment of the corrosion resistance of metallic materials, with or without permanent or temporary corrosion protection. It also describes the method employed to evaluate the corrosivity of the test-cabinet environment. It does not specify the dimensions of test specimens, the exposure period to be used for a particular product, or the interpretation of results. Such details are provided in the appropriate product specifications. The salt spray tests are particularly useful for detecting discontinuities, such as pores and other defects in certain metallic, organic, anodic oxide and conversion coatings. The neutral salt spray test applies to: metals and their alloys; - metallic coatings (anodic and cathodic); - conversion coatings; - anodic oxide coatings; - organic coatings on metallic materials. The acetic acid salt spray test is especially useful for testing decorative coatings of copper + nickel + chromium, or nickel + chromium. It has also been found suitable for testing anodic coatings on aluminum. The copper-accelerated acetic acid salt spray test is useful for testing decorative coatings of copper + nickel + chromium, or nickel + chromium. It has also been found suitable for testing anodic coatings on aluminum. The salt spray methods are all suitable for checking that the comparative quality of a metallic material, with or without corrosion protection, is maintained. They are not intended to be used for comparative testing, to rank different materials relative to each other with respect to corrosion resistance.
Korrosionsprüfungen in künstlichen Atmosphären - Salzprühnebelprüfungen (ISO 9227:2006)
Diese Internationale Norm legt das Gerät, die Reagenzien und das anzuwendende Verfahren bei der Durchführung der neutralen Salzsprühnebelprüfung (NSS, neutral salt spray), der Essigsäure-Salzsprüh-nebelprüfung (AASS, acetic acid salt spray) und der kupferbeschleunigten Essigsäure-Salzsprühnebelprüfung (CASS, copper-accelerated acid salt spray) zum Beurteilen der Korrosionsbeständigkeit von metallischen Werkstoffen mit oder ohne ständigen Korrosionsschutz oder mit temporärem Korrosionsschutz fest.
Die Norm beschreibt auch das Verfahren, mit dem die Korrosivität in der Prüfkammer bewertet werden kann.
Die Norm legt nicht die Maße der Proben, die für ein bestimmtes Produkt anzuwendende Dauer der Beanspruchung oder die Interpretation der Ergebnisse fest. Solche Einzelheiten werden in den entsprechenden Produktspezifikationen angegeben.
Die Salzsprühnebelprüfungen sind besonders nützlich zum Nachweis von Schwachstellen, wie Poren und anderen Schäden, in bestimmten metallischen Überzügen und organischen Beschichtungen sowie anodischen Oxidschichten und Umwandlungsschichten.
Die neutrale Salzsprühnebelprüfung gilt für:
- Metalle und deren Legierungen;
- Metallüberzüge (anodisch oder kathodisch wirksame);
- Umwandlungsschichten;
- anodische Oxidschichten;
- organische Beschichtungen auf metallischen Werkstoffen.
Die Essigsäure-Salzsprühnebelprüfung ist besonders nützlich zum Prüfen dekorativer Überzüge aus Kupfer + Nickel + Chrom oder Nickel + Chrom. Sie ist auch zum Prüfen anodischer Schichten auf Aluminium geeignet.
Die kupferbeschleunigte Essigsäure-Salzsprühnebelprüfung ist nützlich zum Prüfen dekorativer Überzüge aus Kupfer + Nickel + Chrom oder Nickel + Chrom. Sie ist auch zum Prüfen anodischer Überzüge auf Aluminium geeignet.
Essais de corrosion en atmospheres artificielles - Essais aux brouillards salins (ISO 9227:2006)
L'ISO 9227:2006 spécifie l'appareillage, les réactifs et le mode opératoire à utiliser lors des essais au brouillard salin neutre (NSS), au brouillard salin acétique (AASS) et au brouillard salin cupro-acétique (CASS) permettant d'évaluer la résistance à la corrosion de matériaux métalliques, avec ou sans revêtement temporaire ou permanent de protection contre la corrosion.
Elle décrit également la méthode à appliquer pour évaluer la corrosivité du milieu de la chambre d'essai.
Korozijsko preskušanje v umetnih atmosferah – Korozijski preskusi v slani komori (ISO 9227:2006)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 9227:2006
01-oktober-2006
Korozijsko preskušanje v umetnih atmosferah – Korozijski preskusi v slani komori
(ISO 9227:2006)
Corrosion tests in artificial atmospheres - Salt spray tests (ISO 9227:2006)
Korrosionsprüfungen in künstlichen Atmosphären - Salzprühnebelprüfungen (ISO
9227:2006)
Essais de corrosion en atmospheres artificielles - Essais aux brouillards salins (ISO
9227:2006)
Ta slovenski standard je istoveten z: EN ISO 9227:2006
ICS:
77.060 Korozija kovin Corrosion of metals
SIST EN ISO 9227:2006 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 9227:2006
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SIST EN ISO 9227:2006
EUROPEAN STANDARD
EN ISO 9227
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2006
ICS 77.060 Supersedes EN ISO 7253:2001
English Version
Corrosion tests in artificial atmospheres - Salt spray tests (ISO
9227:2006)
Essais de corrosion en atmosphères artificielles - Essais Korrosionsprüfungen in künstlichen Atmosphären -
aux brouillards salins (ISO 9227:2006) Salzprühnebelprüfungen (ISO 9227:2006)
This European Standard was approved by CEN on 7 July 2006.
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 Central Secretariat 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 Central Secretariat has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,
Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2006 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 9227:2006: E
worldwide for CEN national Members.
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SIST EN ISO 9227:2006
EN ISO 9227:2006 (E)
Foreword
This document (EN ISO 9227:2006) 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 January 2007, and conflicting national
standards shall be withdrawn at the latest by January 2007.
This document supersedes EN ISO 7253:2001.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: Austria, Belgium,
Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary,
Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
Endorsement notice
The text of ISO 9227:2006 has been approved by CEN as EN ISO 9227:2006 without any
modifications.
2
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SIST EN ISO 9227:2006
INTERNATIONAL ISO
STANDARD 9227
Second edition
2006-07-15
Corrosion tests in artificial
atmospheres — Salt spray tests
Essais de corrosion en atmosphères artificielles — Essais aux
brouillards salins
Reference number
ISO 9227:2006(E)
©
ISO 2006
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SIST EN ISO 9227:2006
ISO 9227:2006(E)
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Published in Switzerland
ii © ISO 2006 – All rights reserved
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SIST EN ISO 9227:2006
ISO 9227:2006(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope . 1
2 Normative references . 2
3 Test solutions. 2
3.1 Preparation of the sodium chloride solution .2
3.2 pH adjustment . 2
3.3 Filtration. 3
4 Apparatus . 3
4.1 Component protection . 3
4.2 Spray cabinet . 3
4.3 Heater and temperature control . 3
4.4 Spraying device . 4
4.5 Collecting devices . 4
4.6 Re- use . 5
5 Method of evaluation of the corrosivity of the cabinet. 5
5.1 General. 5
5.2 NSS test . 5
5.3 AASS test. 6
5.4 CASS test. 7
6 Test specimens . 9
7 Arrangement of the test specimens. 9
8 Operating conditions. 10
9 Duration of tests . 10
10 Treatment of specimens after test . 11
11 Evaluation of results. 11
12 Test report . 11
Annex A (informative) Schematic diagram of one possible design of spray cabinet with means for
treating fog exhaust and drain . 13
Annex B (informative) Complementary method for evaluation of the corrosivity of the cabinet by
use of zinc reference specimens . 15
Annex C (normative) Preparation of panels with organic coatings for testing . 17
Annex D (normative) Required supplementary information for testing test panels
with organic coatings. 18
Bibliography . 19
© ISO 2006 – All rights reserved iii
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SIST EN ISO 9227:2006
ISO 9227:2006(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. 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.
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.
ISO 9227 was prepared by Technical Committee ISO/TC 156, Corrosion of metals and alloys, in collaboration
with ISO/TC 35, Paints and varnishes, Subcommittee SC 9, General test methods for paints and varnishes,
and ISO/TC 107, Metallic and other inorganic coatings, Subcommittee SC 7, Corrosion tests.
This second edition cancels and replaces the first edition (ISO 9227:1990) and ISO 7253:1996, which have
been technically revised.
iv © ISO 2006 – All rights reserved
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SIST EN ISO 9227:2006
ISO 9227:2006(E)
Introduction
There is seldom a direct relation between resistance to the action of salt spray and resistance to corrosion in
other media, because several factors influencing the progress of corrosion, such as the formation of protective
films, vary greatly with the conditions encountered. Therefore, the test results should not be regarded as a
direct guide to the corrosion resistance of the tested metallic materials, in all environments where these
materials may be used. Also, the performance of different materials, during the test should not be taken as a
direct guide to the corrosion resistance of these materials in service.
Nevertheless, the method described gives a means of checking that the comparative quality of a metallic
material, with or without corrosion protection, is maintained.
Salt spray tests are generally suitable as corrosion protection tests for rapid analysis for discontinuities, pores
and damage in organic and inorganic coatings. In addition, for quality control purposes, comparison can be
made between specimens coated with the same coating. As comparative tests, however, salt spray tests are
only suitable if the coatings are sufficiently similar in nature.
It is often not possible to use results gained from salt spray testing as a comparative guide to the long-term
behaviour of different coating systems, as the corrosion stress during these tests differs significantly from the
corrosion stresses encountered in practice.
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SIST EN ISO 9227:2006
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SIST EN ISO 9227:2006
INTERNATIONAL STANDARD ISO 9227:2006(E)
Corrosion tests in artificial atmospheres — Salt spray tests
1 Scope
This International Standard specifies the apparatus, the reagents and the procedure to be used in conducting
the neutral salt spray (NSS), acetic acid salt spray (AASS) and copper-accelerated acetic acid salt spray
(CASS) tests for assessment of the corrosion resistance of metallic materials, with or without permanent or
temporary corrosion protection.
It also describes the method employed to evaluate the corrosivity of the test-cabinet environment.
It does not specify the dimensions of test specimens, the exposure period to be used for a particular product,
or the interpretation of results. Such details are provided in the appropriate product specifications.
The salt spray tests are particularly useful for detecting discontinuities, such as pores and other defects in
certain metallic, organic, anodic oxide and conversion coatings.
The neutral salt spray test applies to:
⎯ metals and their alloys;
⎯ metallic coatings (anodic and cathodic);
⎯ conversion coatings;
⎯ anodic oxide coatings;
⎯ organic coatings on metallic materials.
The acetic acid salt spray test is especially useful for testing decorative coatings of
copper + nickel + chromium, or nickel + chromium. It has also been found suitable for testing anodic coatings
on aluminum.
The copper-accelerated acetic acid salt spray test is useful for testing decorative coatings of
copper + nickel + chromium, or nickel + chromium. It has also been found suitable for testing anodic coatings
on aluminum.
The salt spray methods are all suitable for checking that the comparative quality of a metallic material, with or
without corrosion protection, is maintained. They are not intended to be used for comparative testing, to rank
different materials relative to each other with respect to corrosion resistance.
© ISO 2006 – All rights reserved 1
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SIST EN ISO 9227:2006
ISO 9227:2006(E)
2 Normative references
The following referenced documents are indispensable for the application 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 1514:2004, Paints and varnishes — Standard panels for testing
1)
ISO 2808:— , Paints and varnishes — Determination of film thickness
ISO 3574:1999, Cold-reduced carbon steel sheet of commercial and drawing qualities
2)
ISO 8407:— , Corrosion of metals and alloys — Removal of corrosion products from corrosion test
specimens
3)
ISO 17872:— , Paints and varnishes — Guidelines for the introduction of scribe marks through coatings on
metallic panels for corrosion testing
3 Test solutions
3.1 Preparation of the sodium chloride solution
Dissolve a sufficient mass of sodium chloride in distilled or deionized water with a conductivity not higher than
20 µS/cm at 25 °C ± 2 °C to produce a concentration of 50 g/l ± 5 g/l. The sodium chloride concentration of
the sprayed solution collected shall be 50 g/l ± 5 g/l. The specific gravity range for a 50 g/l ± 5 g/l solution is
1,029 to 1,036 at 25 °C.
The sodium chloride shall contain less than 0,001 % mass fraction of copper and less than 0,001 % mass
fraction of nickel, as determined by atomic absorption spectrophotometry or another analytical method of
similar sensitivity. It shall not contain more than 0,1 % of a mass fraction of sodium iodide, or more than 0,5 %
of a mass fraction of total impurities calculated for dry salt.
NOTE If the pH of prepared solution at 25 °C ± 2 °C is outside the range 6,0 to 7,0, investigate the presence of
undesirable impurities in the salt and/or the water.
3.2 pH adjustment
3.2.1 pH of the salt solution
Adjust the pH of the salt solution to the desired value on the basis of the pH of the sprayed solution collected.
3.2.2 NSS test
Adjust the pH of the salt solution (3.1) so that the pH of the sprayed solution collected within the test cabinet
(4.2) is 6,5 to 7,2 at 25 °C ± 2 °C. Check the pH using electrometric measurement or in routine checks, with a
short-range pH paper, which can be read in increments or 0,3 pH units or less. Make any necessary
correction by adding hydrochloric acid, sodium hydroxide or sodium bicarbonate solution of analytical grade.
1) To be published. (Revision of ISO 2808:1997)
2) To be published. (Revision of ISO 8407:1991)
3) To be published.
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SIST EN ISO 9227:2006
ISO 9227:2006(E)
Possible changes in pH may result from loss of carbon dioxide from the solution when it is sprayed. Such
changes may be avoided by reducing the carbon dioxide content of the solution by, for example, heating it to a
temperature above 35 °C before it is placed in the apparatus, or by making the solution using freshly boiled
water.
3.2.3 AASS test
Add a sufficient amount of glacial acetic acid to the salt solution (3.1) to ensure that the pH of samples of
sprayed solution collected in the test cabinet (4.2) is between 3,1 and 3,3. If the pH of the solution initially
prepared is 3,0 to 3,1, the pH of the sprayed solution is likely to be within the specified limits. Check the pH
using electrometric measurement at 25 °C ± 2 °C, or, in routine checks, with a short-range pH paper which
can be read in increments of 0,1 pH units or less. Make any necessary correction by adding glacial acetic acid
or sodium hydroxide of analytical grade.
3.2.4 CASS test
Dissolve a sufficient mass of copper(II) chloride dihydrate (CuCl⋅2H O) in the salt solution (3.1) to produce a
2 2
concentration of 0,26 g/l ± 0,02 g/l [equivalent to (0,205 ± 0,015) g of CuCl per litre].
2
Adjust the pH using the procedures described in 3.2.2.
3.3 Filtration
If necessary, filter the solution before placing it in the reservoir of the apparatus, to remove any solid matter
which might block the apertures of the spraying device.
4 Apparatus
4.1 Component protection
All components in contact with the spray or the test solution shall be made of, or lined with, materials resistant
to corrosion by the sprayed solution and which do not influence the corrosivity of the sprayed test solutions.
4.2 Spray cabinet
3
The cabinet shall have a capacity of not less than 0,4 m since, with smaller volumes, difficulties have been
experienced in ensuring an even distribution of spray. For large-capacity cabinets, it is necessary to ensure
that the conditions of homogeneity and distribution of the spray are met. The upper parts of the cabinet shall
be designed so that drops of sprayed solution formed on its surface do not fall on the specimens being tested.
The size and shape of the cabinet shall be such that the collection rate of solution in the cabinet is within the
limits specified in Table 2, measured as specified in 8.3.
It is preferred that the apparatus has a means to properly treat the fog after the test, prior to releasing it from
the building for environmental conservation, and also to drain water prior to discharging it to the drainage
system.
NOTE A schematic diagram of one possible design of spray cabinet is shown in Annex A.
4.3 Heater and temperature control
An appropriate system maintains the cabinet and its contents at the specified temperature (see Table 2). The
temperature shall be measured at least 100 mm from the walls.
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SIST EN ISO 9227:2006
ISO 9227:2006(E)
4.4 Spraying device
The device for spraying the salt solution comprises a supply of clean air, of controlled pressure and humidity,
a reservoir to contain the solution to be sprayed, and one or more atomizers.
The compressed air supplied to the atomizers shall be passed through a filter to remove all traces of oil or
4)
solid matter, and the atomizing pressure shall be at an overpressure of 70 kPa to 170 kPa.
NOTE Atomizing nozzles may have a “critical pressure” at which an abnormal increase in the corrosiveness of the
salt spray occurs. If the “critical pressure” of a nozzle has not been established with certainty, control of fluctuations in the
air pressure within ± 0,7 kPa, by installation of a suitable pressure regulator valve, minimizes the possibility that the nozzle
will be operated at its “critical pressure”.
In order to prevent evaporation of water from the sprayed droplets, the air shall be humidified before entering
the atomizer, by passage through a saturation tower containing hot distilled water or deionized water at a
temperature 10 °C above that of the cabinet. The appropriate temperature depends on the pressure used and
on the type of atomizer nozzle and shall be adjusted so that the rate of collection of spray in the cabinet, and
the concentration of the collected spray, are kept within the specified limits (see 8.3). In Table 1, guiding
values for the hot water temperature in the saturation tower at different pressures are given. The level of the
water shall be maintained automatically to ensure adequate humidification.
Table 1 — Guiding values for the temperature of the hot water in the saturation tower
Guiding values for temperature, °C, of the hot water
Atomizing
in the saturation tower when performing the different
over-pressure
salt spray tests
Neutral salt spray (NSS)
Copper-accelerated acetic
kPa and acetic acid salt spray
acid salt spray (CASS)
(AASS)
70 45 61
84 46 63
98 48 64
112 49 66
126 50 67
140 52 69
The atomizers shall be made of inert material. Baffles may be used to prevent direct impact of spray on the
test specimens, and the use of adjustable baffles is helpful in obtaining uniform distribution of the spray within
the cabinet. For this purpose, a dispersion tower equipped with an atomizer may also be helpful. The level of
the salt solution in the salt reservoir shall be maintained automatically to ensure uniform spray delivery
throughout the test.
4.5 Collecting devices
At least two suitable collecting devices shall be available, consisting of funnels made of chemically inert
material, with the stems inserted into graduated cylinders or other similar containers. Suitable funnels have a
2
diameter of 100 mm, which corresponds to a collecting area of approximately 80 cm . The collecting devices
shall be placed in the zone of the cabinet where the test specimens are placed, one close to an inlet of spray
and one remote from an inlet. They shall be placed so that only mist, and not liquid falling from specimens or
from parts of the cabinet, is collected.
2
4) 1 kPa = 1 kN/m = 0,01 atm = 0,01 bar = 0,145 psi.
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SIST EN ISO 9227:2006
ISO 9227:2006(E)
4.6 Re-use
If the cabinet has been used once for an AASS or CASS test, or has been used for any other purpose with a
solution differing from that specified for the NSS test, it shall not be used for the NSS test.
It is nearly impossible to clean a cabinet that was once used for AASS or CASS testing so that it can be used
for a NSS test. However, in this circumstance, the equipment shall be thoroughly cleaned, and then checked
by the method described in Clause 5; particularly ensuring that the pH of the collected solution is correct
throughout the entire spraying period. After this procedure, the specimens to be tested are placed in the
cabinet.
5 Method of evaluation of the corrosivity of the cabinet
5.1 General
To check the reproducibility and repeatability of the test results for one piece of apparatus, or for similar items
of apparatus in different laboratories, it is necessary to verify the apparatus at regular intervals as described
in 5.2 to 5.4.
NOTE During permanent operation, a reasonable time period between two checks of the corrosivity of the apparatus
is generally considered to be 3 months.
To determine the corrosivity of the tests, reference-metal specimens of steel shall be used.
As a complement to reference-metal specimens made of steel, high-purity zinc reference-metal specimens
may also be exposed in the tests, to determine the corrosivity against this metal as described in Annex B.
5.2 NSS test
5.2.1 Reference specimens
To verify the apparatus, use four or six reference specimens of 1 mm ± 0,2 mm thickness and
5)
150 mm × 70 mm, of CR4 grade steel in accordance with ISO 3574, with an essentially faultless surface ,
and a matt finish (arithmetically mean deviation of the profile Ra = 0,8 µm ± 0,3 µm). Cut these reference
specimens from cold-rolled plates or strips.
Clean the reference specimens carefully, immediately before testing. Besides the specification given in 6.2
and 6.3, cleaning shall eliminate all those traces (dirt, oil or other foreign matter), which could influence the
test results.
Thoroughly clean the reference specimens with an appropriate organic solvent (such as a hydrocarbon with a
boiling point between 60 °C and 120 °C) using a clean soft brush or an ultrasonic cleaning device. Carry out
the cleaning in a vessel full of solvent. After cleaning, rinse the reference specimens with fresh solvent and
then dry them.
Determine the mass of the reference specimens to ± 1 mg. Protect one face of the reference specimens with
a removable coating, for example an adhesive plastic film. The edges of the reference test specimens may be
protected by the adhesive tape as well.
5) “Essentially faultless” means free from pores, marks, scratches and any light colouration.
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SIST EN ISO 9227:2006
ISO 9227:2006(E)
5.2.2 Arrangement of the reference specimens
Position four steel reference specimens in four quadrants (if six specimens are available, place them in six
different positions including four quadrants) in the zone of the cabinet where the test specimens are placed,
with the unprotected face upwards, and at an angle of 20° ± 5° from the vertical.
The support for the reference specimens shall be made of, or coated with, inert materials such as plastics.
The lower edge of the reference specimens shall be level with the top of the salt spray collector. The test
duration shall be 48 h.
Test specimens of types different from the reference specimens shall not be placed in the test cabinet during
the verification procedure.
5.2.3 Determination of mass loss (mass per area)
At the end of the test, immediately take the reference specimens out of the test cabinet and remove the
protective coating. Remove the corrosion products by mechanical and chemical cleaning as described in
ISO 8407. Use, for chemical cleaning, a solution with a mass fraction of 20 % of diammonium citrate
[(NH ) HC H O )] (recognized analytical grade) in water for 10 min at 23 °C.
4 2 6 5 7
After each stripping, thoroughly clean the reference specimens at ambient temperature with water, then with
ethanol, followed by drying.
Weigh t
...
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