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INTER NATIONAL
3897
STANDARD
Third edition
1992-1 2-1 5
Photography - Processed photographic
plates - Storage practices
Photographie - Plaques photographiques développées - Directives
pour l'archivage
Reference number
IS0 3897: 1992( E)
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IS0 38971992(E)
Foreword
IS0 (the International Organization for Standardization) is a worldwide
federation of national standards bodies (IS0 member bokiies). The work
of preparing International Standards is normally carried out through IS0
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, govern-
mental and non-governmental, in liaison with ISO, also take part in the
work. IS0 collaborates closely with the International Electrotechnical
Commission (IEC) on all matters of electrotechnical standardization.
Draft International Standards adopted by the technical committees are
circulated to the member bodies for voting. Publicatidn as an Inter-
national Standard requires approval by at least 75% of the member
bodies casting a vote.
International Standard IS0 3897 was prepared by Technical Committee
ISO/TC 42, Photography.
This third edition cancels and replaces the second edition
(IS0 3897:1986), of which it contitutes a technical revision.
Annexes A, B, C, D, E, F and G of this International Standard are for in-
formation only.
0 IS0 1992
All rights reserved. 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 the publisher.
for Standardlzatlon
International Organization
Case Postale 56 CH-I211 Genève 20 Switzerland
Printed in Switzerland
ii
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IS0 3897:1992(E)
Introduction
Photographic plates on glass or metal supports have been in existence
almost since the beginning of photography. Plates made many years
ago and now stored in archives or other collections are invaluable and
eminently worthy of preservation. Present-day usage of photographic
plates dictates many special requirements, which may give them ap-
preciable value.
There are many factors which may contribute to the deterioration of
photographic plates. These factors can be divided into three general
categories:
a) Nature of the photographic plate
The stability of photographic-plate records depends on the physical
and chemical nature of the material. Some obsolete types of photo-
graphic plate still exist and require preservation in archives, mu-
seums, and other collections. These plates are covered by the
recommendations in this International Standard. The permanent-
record nature of some types of photographic plate has been estab-
lished by many years of storage (over 100 years in many instances).
However, it is difficult to distinguish between various types of plate
covered by the definitions (see clause 3), with respect to storage life.
Nothing in the practices described should be construed as a rec-
ommendation for mixing the various types in storage. Although the
same recommendations apply to plates of both short-term and long-
term interest, much greater care should be taken to obtain maximum
protection for plates of long-term interest.
b) Photographic processing of the plate
The importance of processing procedures to the preservation of
plates should be emphasized. Plates should be thoroughly fixed and
washed after development to ensure the required image stability and
to remove unused silver halide and chemicals used during pro-
cessing. Residual thiosulfate in processed images should be low for
long-term stability. Although this has not been specified for plates in
any International Standard, IS0 10602 may be used as a guideline for
archival storage of photographic plates. Residual thiosulfate may be
determined according to IS0 417. The drying process plays an es-
sential role in avoidance of emulsion layer shrinkage, water spots
and distortion.
c) Storage conditions
The conditions under which photographic plates should be stored are
extremely important for the preservation of plates and are the sub-
ject of this International Standard.
The important elements affecting preservation of processed plates
are humidity, temperature and pollutants of the air, as well as the
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IS0 3897:1992(E)
hazards of water, light, fungal growth, insects, microbiological attack,
contact with certain chemicals in solid, liquid or gaseous form, and
physical damage.
I
The extent to which humidity, temperature, pollutants or variations
thereof can be permitted to reach beyond recommended limits with-
out producing adverse effects will depend on the duration of expo-
sure, on biological conditions conducive to fungal growth, and on the
accessibility of this atmosphere to the plate surfaces.
The recommendations of this International Standard also pertain to
fire protection, plate handling and inspection. This International
Standard does not give recommendations concerhing protection
against natural or man-made catastrophes with the dxception of fire
and associated hazards which are sufficiently comrhon to warrant
inclusion of protective measures.
In addition to the specifications in this International Standard, good
storage practice should consider the filing enclosure. These are
covered in IS0 10214.
iv
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INTERNATIONAL STANDARD IS0 3897:1992(E)
Photography - Processed photographic plates - Storage
practices
are unknown, that have been toned or retouched,
1 Scope
or bear markings with materials of uncertain or un-
known stability. It is not intended to predict or assign
0 1.1 This International Standard gives rec-
a useful lifetime to photographic plates stored in
ommendations for the storage conditions, storage
accordance with the specifications of this Inter-
facilities, handling and inspection of processed
national Standard.
photographic plates.
1.2 This International Standard defines terms and
2 Normative references
recommends practices for the storage of black-and-
white, silver-image, photographic plates having in-
The following standards contain provisions which,
tegral photographic layers and intended for record
through reference in this text, constitute provisions
purposes.
of this International Standard. At the time of publi-
cation, the editions indicated were valid. All stan-
No specific distinction is made, other than the de-
dards are subject to revision, and parties to
gree of care, between plates for medium-term or
agreements based on this International Standard
archival storage.
are encouraged to investigate the possibility of ap-
plying the most recent editions of the standards in-
Recommendations for plate storage relate to ma-
dicated below. Members of IEC and IS0 maintain
terials, methods, conditions, and forms of protection
registers of currently valid International Standards.
applicable specifically to plates defined in 3.3. How-
ever, the storage recommendations may also be
IS0 41 7:-’), Photography - Determination of re-
applied to colour plates, to black-and-white plates
sidual thiosulfate and other related chemicals in
altered by dyes or toners, and to the plates defined
processed photographic materials - Methods using
in 3.4, 3.5, 3.6, 3.7 and 3.8.
iodine-amylose, methylene blue and silver sulfide.
1.3 The storage of photographic film and paper
IS0 1974:1990, Paper - Determination of tearing re-
requires different considerations and these are not
sistance (Elmendori method).
covered in this International Standard but are
covered in IS0 5466 and IS0 6051, respectively.
IS0 10214:1991, Photography - Processed photo-
graphic materials - Filing enclosures for storage.
1.4 Although not covered by this International
IS0 10602:1992*), Photography - Processed silver-
Standard, lacquered and opaqued plates will have
gelatin type black-and-white film - Specifications for
their useful life prolonged under the storage con-
stability.
ditions recommended. However, they should not be
stored with non-lacquered or non-opaqued plates.
3 Definitions
1.5 This International Standard, while intended for
materials that are well processed, should also be of
considerable value in prolonging the useful life of For the purposes of this International Standard, the
photographic plates whose processing conditions following definitions apply.
1) To be published. (Revision of IS0 417:1977)
2) To be published.
1
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IS0 3897:1992(E)
3.1 photographic plate: A photographic layer on temperatures, water and other fire-fighting agents,
“soda-line-silica’’ sheet glass, except for the type of
steam developed by insulation of safes, and col-
plate defined in 3.6.
lapsing structures.
3.2 photographic layer: A light-sensitive coating 3.12 insulated record container: Container as de-
fined in appropriate national standards and regu-
containing silver halide which yields a visible image
after exposure and processing. I at i O n s .4)
3.13 fire-resistant vault: Vault as defined in appro-
3.3 (gelatin) dry plate: A glass sheet with a silver
pria t e n at ion a I s t a n d a rd s a n d reg U 1 at ions .5)
halide/gelatin coating which has been exposed and
processed to form a silver image.
3.14 open enclosure: Enclosure which is intended
for physical protection against mechanical damage,
3.4 wet or dry collodion plate; wet or dry plate: A
but is neither lighttight nor airtight.
glass sheet bearing a thin silver halide/cellulose ni-
trate layer which has been exposed and processed
Folders, envelopes, cartons, sleeves, transparency
to form a silver image.
mounts, and jackets are examples of protective en-
closures.
3.5 ambrotype plate: A type of wet collodion glass
plate on which the processed silver image appears
3.15 protective enclosure: Lighttight, impermeable
as a positive when backed by a dark field.
container used for protection from outside factors
such as reactive gases and moisture, including
3.6 ferrotype plates); tintype: An enamelled iron
relative humidity changes.
sheet bearing a thin silver halide/cellulose nitrate
layer which has been exposed and processed to
Sealed envelopes (see A.2.4) are examples of pro-
form a silver image and which appears in positive
tective enclosures.
form.
4 Plate enclosures
3,7 colour screen plate: A glass sheet bearing a
colour screen consisting of dyed elements in contact
4.1 Classification of enclosures
with a positive silver image.
Plates require protection against all types of physi-
3.8 albumen plate: A glass sheet bearing a silver
cal damage such as breakage, scratches, abrasion,
halide/albumen layer which has been exposed and
fingerprints, etc. Enclosures for storage of pro-
processed to form a silver image.
cessed photographic plates may be divided into two
classifications: individual enclosures and multiple-
3.9 medium-term storage: Those storage con-
plate containers. Storage arrangements are de-
ditions suitable for ensuring a minimum useful life
pendent on the physical dimensions of the plate.
of 10 years.
3.10 archival storage: Those storage conditions 4.2 Individual enclosures
O
suitable for the preservation of photographic ma-
terials having permanent value.
Individual plates (except fine-grain plates and small
size plates) should be placed in suitable individual
NOTES
envelopes, sleeves or folders (see annex A) to ex-
clude dirt, to protect the plates against mechanical
1 Archival storage conditions will prolong the useful life
damage and to facilitate identification and handling.
of plates, whether or not they have had optimum pro-
It is important to avoid any contact with the image
cessing.
surface of small plates (for example up to
10 cm x 15 cm) and fine-grain types, which should
2 The term “archival” as used in photography and de-
preferably be stored in a multiple-plate container of
fined as in this International Standard is frequently being
misapplied in related fields of imaging. ISO/TC 42 will the type recommended in 4.3.
therefore replace the term “archival storage” with
“extended-term storage” or specify a “life expectancy Plates may be stored in envelopes of paper or
(LE)” classification in future editions of its standards.
paper/foiI/plastic laminates, folding cartons or file
folders. When in direct contact with the surface of
3.11 fire-protection storage: Facilities designed to the photographic plate, the paper or plastic en-
protect photographic materials against excessive closure material shall meet, as a minimum require-
ace upon which high-gloss photographic prints are dried.
3) Not to be confused with a thin metal sheet with a glossy si
4) Example: Class 150 of UL 72 [’I.
5) Example: NFPA 232 [*I.
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IS0 3897:1992(E)
ment, the specifications described in IS0 10214.
4.3.1 Containers for small plates and fine-grain
Sealed enclosures shall be used where needed to
types
maintain humidity within the specified limits (see
clause 7), to protect against gaseous impurities in Small plates up to 10 cm x 15 cm in size and fine-
the atmosphere, or when low-temperature storage grain plates shall be stored in closed rectangular
is used. Heat sealable envelopes consisting of containers. Each container shall be fitted with
aluminium foil extrusion coated with clear grooved inserts which separate the plates from each
polyethylene on the inside and laminated to a suit- other and support them vertically. No supporting
able paper sheet on the outside have been SUC- material shall be in contact with major areas of plate
cessfully used as sealed enclosures. To provide surfaces. The cross-section of the grooves shall
greater protection against pinholes, a double- have the form of a “U” or “V” and contact shall be
bagging technique is recommended. Precautions at the extreme edge of the plate. Depending on plate
shall be taken in handling these envelopes so that size and thickness, 12 to 36 grooves are suitable.
they are not punctured. Enclosures shall not create
excessive pressure on the plate surface. Marks can
4.3.2 Containers for large plates
originate from improperly located seams or wrin-
kles. The filing enclosure shall be constructed so
Large plates in individual enclosures may be stored
that the seam or joint will be at the edge of the en-
in multiple-plate boxes designed to accommodate
closure and not in contact with the image surface.
from 4 to 12 plates, depending on plate size and
Examples of dimensions and construction of filing
thickness. Box dimensions shall permit the plate to
O enclosures are given in annex A.
be on edge when placed in storage. Boxes of this
type are suitable for plates in the size range
Enclosure design shall permit storage of the plate
13 cm x 18 cm to 30 cm x 40 cm or larger. The mass
on edge (i.e. in a vertical plane with one edge par-
of the contents shall control the quantity. The inside
allel to the horizontal). Plates shall not be stored in
dimensions (length and height of the box) shall be
a flat or horizontal position as this could cause ex-
only slightly larger than the length and width of the
cessive pressure on the lower ones. It should be
individual enclosure.
noted that 19th century glass is usually not flat and
horizontal storage of such materials can cause
stress-related fractures. Plates shall not be stored
5 Storage housings
or handled with plate emulsion surfaces in contact.
For optimum storage life, photographic plates shall
Plates should be segregated carefully by type, as
be in a clean condition before being placed in stor-
defined in 3.3, 3.4, 3.5, 3.6, 3.7 and 3.8 and stored in
age. Periodic inspection should be made as de-
a well-separated storage housing to avoid inter-
scribed in 9.2.
actions among various types which might produce
adverse effects if mixing were to occur. It is particu-
larly important to segregate collodion plates, am-
brotype plates and ferrotype plates since they
contain cellulose nitrate. Cellulose nitrate is un-
stable and releases oxides of nitrogen [SI which can
0 4.3 Multiple-plate containers
attack the silver image on adjacent plates.
Multiple-plate containers shall be used where it is
Plate dimensions will normally control the choice of
necessary to avoid plate-to-plate contact. They are
housings, but the mass of the plates should also be
preferable for storing fine-grain types of plates or
considered.
groups of plates and serve as transfer boxes for
handling plates from storage to working area. The storage housing materials shall be non-
corrodible as described in IS0 10214. They shall
Container materials should preferably be metal or
also be non-combustible. Because of their
plastic as described in IS0 10214. Cardboard or
combustible nature and the possibility of producing
wooden containers should be avoided because they
active fading agents on ageing, materials made of
can contain oxidizing materials which can attack the
wood, pressed-board, hardboard, parîicle-board and
silver image (see annex C).
other natural materials shall be avoided.
Two categories of multiple-plate containers are: The finish on housing materials shall be durable and
shall not contribute deleterious effects to the stored
photographic plate. Adverse effects can be pro-
a) containers for a large number (for example 12 to
36) of small or fine-grain plates without individual duced by finishes containing chlorinated or highly-
enclosures; plasticized resins, or by freshly-painted or lacquered
surfaces. Cabinets painted with oil-base paints shall
not be used for 3 months as they can give off per-
b) containers for a small number (for example 4 to
12) of large plates with individual enclosures. oxides.
3
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IS0 3897:1992( E)
When air-conditioned individually, storage housings Door-type cabinets with shelving may be used for
shall be arranged to permit interior circulation of storing small-plate containers as described in 4.3.1.
air to all shelves and drawers to allow uniform hu- Containers should be stored in a single layer with
midity conditions. Storage housings located in the plates vertical.
rooms conditioned in accordance with 7.1 shall be
provided with ventilation openings permitting access
of air to the interior. Such openings shall not affect
6 Storage rooms
accordance with requirements for fire-protection
storage (see clause 8) or water protection.
The value of photographic plates kept for long-term
Storage housing is of two types: or archival purposes makes it advisable to provide
a storage room or vault separate from temporary
- type 1: Cabinets for plates in individual en- storage facilities, offices or work areas. Good
closures; housekeeping is essential. Walls and enclosures of
air-conditioned spaces shall be designed to prevent
- type 2: Cabinets, shelves or racks for plates in
condensation of moisture on interior surfaces and
multiple-plate containers or for large plates. within walls, especially during periods of low exte-
rior temperatures when the wails can be cooled be-
NOTE 3 Type 2 housing is preferable for enclosures
low the dew point of the air. Provisions shall be
larger than 30 cm x 40 cm.
made against damage by water from floods, leaks,
sprinklers, etc. Storage rooms or vaults should be 0
located above basement leve I s , where poss i b I e.
5.1 Type 1 housings
Storage rooms have been constructed in caves and
mines and have proven very satisfactory when ac-
Individual enclosures should be stored in drawer-
cepted requirements for the environmental con-
type cabinets. Modified office-type drawer filing
ditions (see 7.1 and 7.2) and air purity (see 7.4) are
cabinets are suitable. Enclosures shall be filed with
met.
the plates vertically in the drawers, in one or more
horizontal rows depending on the plate size. The
drawers should be flat-bottomed and the vertical
height of the drawer should correspond to the verti-
7 Environmental conditions
cal dimension of the enclosure. Enclosures should
be grouped by size and the drawer height should
The humidity and temperature of the air in contact
preclude filing more than one vertical row of en-
with plates and the presence of air-entrained solid
closures.
or gaseous impurities are important external factors
The drawers should be divided by suitable partitions affecting plate permanence. For long-term inactive
between horizontal rows. The rows s
...