SIST ISO 18934:2011

SLOVENSKI STANDARD
SIST ISO 18934:2011
01-julij-2011
8SRGRELWYHQLPDWHULDOL9HþQDPHQVNLPHGLMVNLDUKLYL2NROMH]DVKUDQMHYDQMH
Imaging materials - Multiple media archives - Storage environment
Matériaux pour l'image - Archives multimédia - Environnement de stockage
Ta slovenski standard je istoveten z: ISO 18934:2006
ICS:
35.220.99 Druge naprave za Other data storage devices
shranjevanje podatkov
37.040.99 Drugi standardi v zvezi s Other standards related to
fotografijo photography
SIST ISO 18934:2011 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------

SIST ISO 18934:2011

---------------------- Page: 2 ----------------------

SIST ISO 18934:2011


INTERNATIONAL ISO
STANDARD 18934
First edition
2006-05-15

Imaging materials — Multiple media
archives — Storage environment
Matériaux pour l'image — Archives multimédia — Environnement de
stockage



Reference number
ISO 18934:2006(E)
©
ISO 2006

---------------------- Page: 3 ----------------------

SIST ISO 18934:2011
ISO 18934:2006(E)
PDF disclaimer
This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but
shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In
downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat
accepts no liability in this area.
Adobe is a trademark of Adobe Systems Incorporated.
Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation
parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In
the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below.


©  ISO 2006
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland

ii © ISO 2006 – All rights reserved

---------------------- Page: 4 ----------------------

SIST ISO 18934:2011
ISO 18934:2006(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope. 1
2 Normative references. 1
3 Terms and definitions. 1
4 Recommendations. 3
4.1 Temperature range. 3
4.2 Temperature cycling. 4
4.3 Relative humidity range. 5
4.4 Relative humidity cycling. 5
5 Selecting environmental conditions for mixed media archives . 6
Annex A (informative) Numbering system for related International Standards. 8
Annex B (informative) Stability of electrophotographic, dye sub, inkjet prints. 10
Bibliography . 11

© ISO 2006 – All rights reserved iii

---------------------- Page: 5 ----------------------

SIST ISO 18934:2011
ISO 18934:2006(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 18934 was prepared by Technical Committee ISO/TC 42, Photography.
This International Standard is one of a series of International Standards dealing with the physical properties
and stability of imaging materials. To facilitate identification of these International Standards, they are
assigned a number within the block from 18900 to 18999 (see Annex A).
iv © ISO 2006 – All rights reserved

---------------------- Page: 6 ----------------------

SIST ISO 18934:2011
ISO 18934:2006(E)
Introduction
Over the years, technical committees ISO/TC 36 and ISO/TC 42 of the International Organization for
Standardization have published ISO storage standards specific to individual materials. Many of these
temperature/relative humidity recommendations are based on laboratory studies using Arrhenius type
projections that allow extrapolation of high temperature incubation tests to recommended storage
environments at reduced temperatures. This also allows a prediction of the life expectancy of materials. This
approach and the resulting analysis are logical when each medium is considered by itself. The individual ISO
storage standards are sound and the predicted life expectancies have been consistent with practical
experience. However, the storage conditions can differ widely for various media and reflect differences in their
inherent stability. The extended-term storage conditions recommended in the various standards provide wide
humidity ranges and set only a maximum temperature limit with considerable overlap in allowed environmental
conditions across several media types.
In the real world, archivists and curators frequently are faced with the task of storing many types of material,
such as film, prints, tapes, etc. Archives often contain media that cannot be separated without destroying the
integrity of the collection. In other archives, one collection can consist primarily of one medium, but there are
many collections each with different media. In either situation, it may not be practical or realistic for the
archivist to provide a number of different storage environments that are optimized for each material. The cost
and inconvenience would be prohibitive; moreover, records of the same or similar subject matter are usually
stored in close proximity to facilitate reference, not by the type of medium. The archivist of a multiple media
collection may be forced to limit the number of storage environments that can be provided. In some cases, this
means some deviation from the ISO storage recommendations and can compromise the life expectancies
specified in the standards. This compromise can be based on the value, physical size, quantity, or legal
requirements to maximize life expectancy of some collections relative to others.
This International Standard provides an assessment of the keeping qualities for four storage environments. As
such, it is most useful for storage facilities which house different types of materials, but does not override the
ISO recommendations for single medium collections.
This International Standard does not discuss the various strategies to upgrade substandard environments that
deviate from those recommended by ISO standards. However, institutions with substandard environments and
restricted budgets should plan for the improvement of these environments as resources allow by judicious use
of air conditioning, dehumidifiers (or humidifiers), air circulation and filtration. Although practicalities can force
compromises, any improvement of poor conditions will add to the longevity of materials, even if they do not
attain the life expectancies possible with the environments recommended in the ISO standards. A discussion
of basic air conditioning principles, the various options and the associated costs are outside the scope of this
International Standard. There are many references on this subject.

© ISO 2006 – All rights reserved v

---------------------- Page: 7 ----------------------

SIST ISO 18934:2011

---------------------- Page: 8 ----------------------

SIST ISO 18934:2011
INTERNATIONAL STANDARD ISO 18934:2006(E)

Imaging materials — Multiple media archives — Storage
environment
1 Scope
This International Standard provides suggested guidelines for four temperature and humidity
macroenvironments for archives that contain a variety of recording media, based on the corresponding ISO
storage standards for those media. Whenever possible, it is advisable to follow the storage environments in
the ISO storage standards. This International Standard does not replace these ISO storage standards. In
addition to environment recommendations, those standards also include other vital information pertinent for
the long-term keeping of recording materials, such as inspection, housing, and handling guidelines. Although
microenvironments within a storage enclosure can be dependent upon the macroenvironment, they are not
the focus of this International Standard.
The storage of traditional paper collections is not within the scope of this International Standard. However,
many archives containing mixed recording media also include such collections. Archivists are encouraged to
review the appropriate standards (see References [1] and [2] in the Bibliography) for those materials.
Nitrate-base photographic films are also included in this International Standard, since they are often stored
together with other materials in spite of the fact that nitrate films represent a fire hazard and they need to be
[3]
stored in accordance with the National Fire Protection Association standard in the United States, or other
applicable national standards. Moreover, fumes from decomposing nitrate film and acetate-base film can have
[11]
very detrimental effects on other materials stored in the same area. It is necessary to isolate such films in a
separate storage area.
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 10356, Cinematography — Storage and handling of nitrate-base motion-picture films
ISO 18911, Imaging materials — Processed safety photographic films — Storage practices
ISO 18918, Imaging materials — Processed photographic plates — Storage practices
ISO 18920, Imaging materials — Processed photographic reflection prints — Storage practices
ISO 18923, Imaging materials — Polyester-base magnetic tape — Storage practices
ISO 18925, Imaging materials — Optical disc media — Storage practices
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
conditioning
exposure of a specimen to air at a given relative humidity and temperature until equilibrium is reached
© ISO 2006 – All rights reserved 1

---------------------- Page: 9 ----------------------

SIST ISO 18934:2011
ISO 18934:2006(E)
3.2
extended-term storage conditions
storage conditions suitable for the preservation of recorded information having permanent value
3.3
relative humidity
RH
ratio, defined as a percentage, of the existing partial vapour pressure of water to the vapour pressure at
saturation
NOTE It is usually, but not always, equal to the percentage of the amount of moisture in the air to that at saturation.
3.4
life expectancy
LE
length of time that information is predicted to be acceptable in a system after dark storage at 23 °C and 50 %
RH
3.5
LE designation
rating for the “life expectancy” of recording materials and associated retrieval systems
NOTE The number following the LE designation is a prediction of the minimum life expectancy in years, for which
information can be retrieved without significant loss when stored at 23 °C and 50 % RH, e.g. LE-100 indicates that
information can be retrieved after at least 100 years storage.
3.6
macro-environment
atmospheric conditions (temperature, relative humidity, and pollutants) in a large area in which records are
kept
3.7
magnetic tape
material consisting of a magnetic-sensitive layer coated on a thin plastic support that can produce a magnetic
recording
3.8
medium-term storage conditions
storage conditions suitable for the preservation of recorded information for a minimum of 10 years
3.9
micro-environment
atmospheric conditions (temperature, relative humidity, and pollutants) inside a storage enclosure in which
records are kept
3.10
optical disc
disc that will accept and retain information in the form of marks or density modulations in a recording layer that
can be read with an optical beam
3.11
photographic film
material consisting of one or more radiation-sensitive layers coated on transparent or translucent plastic that
yields a visible image
3.12
photographic paper
material consisting of one or more image-forming layers coated on plain paper, paper with a white pigmented
layer, paper sandwiched between white opaque resin layers or on other opaque supports
2 © ISO 2006 – All rights reserved

---------------------- Page: 10 ----------------------

SIST ISO 18934:2011
ISO 18934:2006(E)
3.13
photographic plate
material consisting of one or more radiation-sensitive layers coated on a rigid support, such as glass or metal,
that yields a visible image
3.14
photographic print
a photographic copy, usually made from a negative, consisting of a layer (or layers) containing a positive
image
NOTE The image layers can be coated on a white opaque, semi-transparent, or transparent support and the images
viewed by reflected or transmitted light.
3.15
recording material
medium that receives images, text or audio information which can subsequently be viewed or retrieved
3.16
storage environment
conditions for storing materials, i.e. temperature, relative humidity, cleanliness of facilities and atmospheric
pollutants
4 Recommendations
4.1 Temperature range
The guidelines for extended-term storage conditions given in this International Standard specify four different
temperature ranges for the storage of mixed media collections:
⎯ room;
⎯ cool;
⎯ cold;
⎯ subzero (see Table 1).
“Room” conditions are satisfactory for materials that are considered to be chemically stable, such as black-
and-white silver and carbon images on polyester base, glass, and paper. “Cool” conditions are suitable for
materials whose stability may be compromised at cold temperatures (magnetic media) and for unstable
materials (e.g. black-and-white acetate film) provided a low RH can be maintained. “Cold” conditions are
recommended for unstable materials, such as colour photographs of all types and cellulosic based films.
“Subzero” conditions should be used to obtain the maximum life for all materials that can tolerate this
environment. It should also be used for unstable materials which have little tolerance for higher temperatures.
In some situations, chemical degradation may have already started as evidenced by the vinegar odour of
deteriorating acetate-base photographic films, by rusted cans or image degradation for nitrate base films, or
by colour deterioration. These materials should always be stored in the “subzero” environment.
The archivist should choose the temperature range which is most suitable for the specific collection with the
objective of obtaining a temperature range as close as possible to the ISO recommendations. Comparisons of
the ISO storage conditions given in the standards for specific materials with the corresponding guidelines in
this International Standard are given in Table 2. Consideration should be given to maintaining a lower set
point temperature during normally cool periods of the year. This may offset slightly higher temperatures in
other seasons where it is impractical to maintain the low temperature.
© ISO 2006 – All rights reserved 3

---------------------- Page: 11 ----------------------

SIST ISO 18934:2011
ISO 1
...