ISO 9022-4:2014

INTERNATIONAL ISO
STANDARD 9022-4
Third edition
2014-11-01
Optics and photonics —
Environmental test methods —
Part 4:
Salt mist
Optique et photonique — Méthodes d’essais d’environnement —
Partie 4: Brouillard salin
Reference number
©
ISO 2014
© ISO 2014
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Contents Page
Foreword .iv
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 General information and test conditions . 1
3.1 Limitations of testing . 1
3.2 Specimens . 2
3.3 Apparatus (see Figure 2) . 3
3.4 Reagents. 5
3.5 Salt spray test conditions . 5
3.6 Test interruption and opening of test chamber . 6
4 Conditioning method 40: Salt mist . 6
5 Procedure. 6
5.1 General . 6
5.2 Preconditioning (specimen preparation) . 6
5.3 Recovery . 7
5.4 Evaluation . 7
6 Environmental test code . 7
7 Specification . 7
Annex A (informative) Explanatory notes . 8
© ISO ISO pub-date year – All rights reserved iii

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 on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical Barriers
to Trade (TBT) see the following URL: Foreword - Supplementary information
The committee responsible for this document is ISO/TC 172, Optics and photonics, Subcommittee SC 1,
Fundamental standards.
This third edition cancels and replaces the second edition (ISO 9022-4:2002), of which it constitutes a
minor revision.
ISO 9022 consists of the following parts, under the general title Optics and photonics — Environmental
test methods:
— Part 1: Definitions, extent of testing
— Part 2: Cold, heat and humidity
— Part 3: Mechanical stress
— Part 4: Salt mist
— Part 6: Dust
— Part 7: Resistance to drip or rain
— Part 8: High pressure, low pressure, immersion
— Part 9: Solar radiation
— Part 11: Mould growth
— Part 12: Contamination
— Part 14: Dew, hoarfrost, ice
— Part 17: Combined contamination, solar radiation
— Part 20: Humid atmosphere containing sulfur dioxide or hydrogen sulfide
iv © ISO ISO pub-date year – All rights reserved

— Part 22: Combined cold, dry heat or temperature change with bump or random vibration
— Part 23: Low pressure combined with cold, ambient temperature and dry and damp heat
© ISO ISO pub-date year – All rights reserved v

Introduction
Optical instruments are affected during their use by a number of different environmental parameters
which they are required to resist without significant reduction in performance and to remain within
defined specifications.
The type and severity of these parameters depend on the conditions of use of the instrument (for
example, in the laboratory or workshop) and on its geographical location. The environmental effects
on optical instrument performance in the tropics and subtropics are totally different from those found
when they are used in arctic regions. Individual parameters cause a variety of different and overlapping
effects on instrument performance.
The manufacturer attempts to ensure, and the user naturally expects, that instruments will resist the
likely rigours of their environment throughout their life. This expectation can be assessed by exposure
of the instrument to a range of simulated environmental parameters under controlled laboratory
conditions. The severity of these conditions is often increased to obtain meaningful results in a relatively
short period of time.
In order to allow assessment and comparison of the response of optical instruments to appropriate
environmental conditions, ISO 9022 contains details of a number of laboratory tests which reliably
simulate a variety of different environments. The tests are based largely on IEC standards, modified
where necessary to take into account features special to optical instruments.
It should be noted that, as a result of continuous progress in all fields, optical instruments are no longer
only precision-engineered optical products, but, depending on their range of application, also contain
additional assemblies from other fields. For this reason, the principal function of the instruments shall
be assessed to determine which International Standard should be used for testing. If the optical function
is of primary importance, then ISO 9022 is applicable, but if other functions take precedence, then the
appropriate International Standard in the field concerned should be applied. Cases can arise where
application of both ISO 9022 and other appropriate International Standards will be necessary.
vi © ISO ISO pub-date year – All rights reserved

INTERNATIONAL STANDARD ISO 9022-4:2014(E)
Optics and photonics — Environmental test methods —
Part 4:
Salt mist
1 Scope
This part of ISO 9022 specifies the methods relating to the environmental tests of optical instruments
including additional assemblies from other fields (e.g. mechanical, chemical, and electronic devices),
under equivalent conditions, for their ability to resist the influence of salt mist.
Exposure to salt mist mainly results in the corrosion of metals. Effects might also occur by way of
clogging or binding of moving parts.
The purpose of the testing is to assess, as early as possible, the ability of the instrument, and particularly
of the surfaces and protective coatings of the instrument, to resist the effects of a salt atmosphere.
Normally, representative samples or complete small units are used for testing. Complete large
instruments or assemblies are only tested as specified in this part of ISO 9022 in exceptional cases.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 9022-1, Optics and photonics — Environmental test methods — Part 1: Definitions, extent of testing
3 General information and test conditions
3.1 Limitations of testing
3.1.1 General
The aim of salt mist testing is unlikely to be achieved, unless the deficiencies and limitations of such
testing as detailed in 3.1.2 and 3.1.3 are fully recognized.
3.1.2 Suitability
Salt mist testing is considered suitable for
a) the assessment of the resistance of optical and other functional layers,
b) the assessment of the anti-corrosion effect of metallic and non-metallic coatings, and
c) the early detection of the unacceptability of material combinations.
3.1.3 Unsuitability
Salt mist tests as specified in this part of ISO 9022 shall not be performed in the following cases:
a) as a general corrosion test, as no verified data are available showing that there is a direct
relationship between salt mist corrosion and corrosion caused by other attacking corrosive media
or environments;
b) on separate components or assemblies that are used only in assembled configurations or any other
configurations protected from corrosion;
c) as a true duplication of natural marine environment.
NOTE Generally, the salt mist test is not reliable for comparing the corrosion resistance of different materials
or the anticorrosive effect of coatings exposed to varying climatic conditions, nor is it suitable for predicting
the service life of such materials or coatings. Some idea of the service life of different specimens of identical or
closely related metals, or of different specimens of identical or comparable protective coating combinations, can
be gained by the salt mist test provided that, by correlating field service test data with laboratory tests, such
relationships can be demonstrated as exist in the case of aluminium alloys. Such correlation tests are essential
if data are required on the accelerating effect (if any) of laboratory testing as compared to performance under
natural service conditions.
3.2 Specimens
Specimens shall be made of the basic materials used for the instrument under test; coatings (finishing
coatings, protective coatings, thin films on optical parts), if any, shall be of the same structure as those
used for the instrument components and surfaces to be assessed.
Specimens for testing metallic and non-metallic coatings shall preferably be metal sheets (sample
sheets) as shown in Figure 1. The coating under test shall completely cover the sample sheet, especially
the outer edges and edges of holes. Where this is not feasible, exposed metal edges shall be protected by
a means that does not affect the coating under test. Marking of the sample sheets shall not damage the
coating to be tested (e. g. punch-marking shall be carried out prior to applying the coating).
Dimensions in millimetres
a
Marking area (on the back).
Figure 1 — Sample sheet
Where the instruments or instrument components to be assessed are made of cast material, the use of
specimens originating from the same batch shall be agreed upon and documented in the test report.
In the test of optical and other functional layers, specimens shall be used as test-pieces which consist of
the same basic materials as the original components.
2 © ISO 2014 – All rights reserved

Complete large instruments and assemblies, or separate components that are used in assembled
configurations only, shall not be tested in accordance with this part of ISO 9022, unless as an exception.
If necessary, essential areas of such specimens and of specimens other than sample sheets (e. g.
electrically insulated components, open assemblies) may be used for assessment by agreement between
the parties concerned.
3.3 Apparatus (see Figure 2)
The test apparatus essentially comprises of the components described below.
...