1、INTERNATIONAL STANDARD First edition 1996-l I-01 Cinematography - Storage and handling of nitrate-base motion-picture films Cingmatographie - En treposage et manipulation de films cinj base de nitrate Reference number IS0 10356:1996(E) IS0 10356:1996(E) Foreword IS0 (the International Organization f
2、or Standardization) is a worldwide federation of national standards bodies (IS0 member bodies). 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 th
3、e right to be represented on that committee. International organizations, governmental 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 In
4、ternational 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. International Standard IS0 10356 was prepared by Technical Committee ISOC 36, Cin
5、ematography. 0 IS0 1996 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 the publisher. International Organization
6、 for Standardization Case Postale 56 l CH-121 1 Geneve 20 l Switzer land Printed in Switzerland II INTERNATIONAL STANDARD IS0 IS0 10356:1996(E) Cinematography - Storage and handling of nitrate-base motion-picture films 1 Scope This International Standard specifies safety aspects for handling and sto
7、rage of radiation-sensitive motion-picture films which do not comply with the requirements of IS0 543. This International Standard applies to all nitrate-base films which are or have been used in motion-picture photographic systems. Compliance with the storage and handling conditions specified in th
8、is International Standard does not ensure protection of the film from deterioration nor reduce its safety hazards. 2 Normative reference The following standard contains provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication,
9、 the edition indicated was valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the standard indicated below. Members of IEC and IS0 maintain registers of cur
10、rently valid International Standards. IS0 543: 1990, Photography - Photographic films - Specifications for safety film. 3 Definitions For the purposes of this International Standard, the following definitions apply. 3.1 radiation-sensitive film: All kinds of radiation-sensitive camera, duplicating a
11、nd printing films and also processed original films, duplicates and prints. 3.2 safety photographic film: Photographic film which passes the ignition time test and burning time test as specified in IS0 543. NOTE - IS0 543, in specifying safety film, makes a primary distinction based upon requiring a
12、 long or infinite burning time for a sample in a specified test. Additional information is given concerning films whose composition is such that they may be expected to fail, or to give ambiguous results in, the burning test. 3.3 nitrate-base film; cellulose nitrate film: Radiation-sensitive nitrate
13、-base film which fails the burning and ignition tests of IS0 543. NOTE .- Because of the precautions required for the safe handling and storage of nitrate-base film, all radiation-sensitive films that do not originally (as opposed to being transferred from some other film) carry the marking specifie
14、d by annex B of IS0 543:1990 should be considered to be nitrate-base films until proven otherwise. 1 IS0 10356:1996(E) IS0 4 Composition (see annex A) The composition of nitrate-base film is described approximately by the following contents, expressed as percentages by mass: - cellulose nitrate 70 %
15、 to 82 % (nitrogen content II,5 % to 12,6 %) - plasticizer - photographic layers - gaseous components 5 % to 15 % 5 % to 15 % I,5 % to 4,5 % WARNING - Although the fundamental hazard of cellulose nitrate is flammability, which has been somewhat reduced by the addition of the plasticizer, it is consi
16、dered an explosive in the sense of laws on explosives. Cellulose nitrate is easily ignited, has a low ignition temperature and a fast burning rate, decomposes even without access to air and during decomposition forms flammable and toxic gases which yield explosive mixtures with air. The decompositio
17、n is exothermic and autocatalytic and can lead to auto- ignition. Heating of cellulose nitrate in closed containers causes explosive decomposition. 5 Identification The identification of nitrate-base films shall be carried out in accordance with IS0 543. 6 Legal requirements for handling Handling of
18、 photograp Ihic nitrate-base films also regulated by laws covering them cals. is regulated by laws covering explosives. The storage of these films is During handling and storage, all relevant laws and regulations on safety aspects shall be observed. All working rooms shall be identified and marked a
19、ccordingly. 7 Transportation Transportation of nitrate-base filn international regulations and laws ( WARNING - Nitrate-base film shall not be transported by mail. and on the road, by rail, at sea and by air shall be in accordance with national e.g. Dangerous Goods Regulation of the International Ci
20、vil Aviation Organizat ion). 8 Storage (see annex B) Nitrate-base films are difficult to store because of their low chemical stability, although experience has shown that the onset of deterioration can vary over a surprisingly long period extending from one to several decades. The useful life depend
21、s not only upon the storage conditions but, in seemingly unpredictable ways, upon variables of prior history of the film. Frequent use of nitrate-base film, involving spooling and unspooling with concurrent exposures of individual convolutions to full ventilation, has been observed to extend the use
22、ful life. Consequently, all films which are kept in archives shall be examined, cleaned and tested on an established schedule (see clause 9). If the film shows signs of deterioration, the subject matter should be preserved while the images remain useful, by duplication or copying to a safety film st
23、ock. The nitrate-base film shall then be destroyed. The deterioration cannot be reversed or arrested. 2 IS0 IS0 10356:1996(E) Rolls of nitrate-base film that have not yet deteriorated shall be placed in individual metal cans (aluminium or stainless steel) with fitted but unsealed closures until they
24、 can be duplicated to safety film. Storage rooms and chambers should contain only nitrate-base film. Good practice requires that the amount of film placed in an individual room be limited, for example, to a maximum of 50 000 m each. Storage rooms should be equipped with appropriate ventilating syste
25、ms, fire sensors, water sprinklers, etc. so that any possible conflagration can be confined to that room. These rooms should be constructed and ventilated so that toxic and flammable fumes and gases cannot reach other rooms. Recommended climatic conditions for storage are given in table 1. Table 1 S
26、torage Maximum temperature Relative humidity “C 0 ( F) % I Short term 1) 25 Long term 2 (77) (36) 25 to 50 20 to 30 I 1) For example, examination, cleaning or duplication. I NOTE - A lower relative humidity can delay deterioration of nitrate-base films and their emulsion images, including reducing t
27、he alteration rates of dyes in colour films. Lower relative humidity will also reversibly change the physical properties, making the film more brittle and subject to accidental damage. This effect can be reversed by providing a suitable period of acclimatization to relative humidities of 40 % to 50
28、% prior to unspooling. In any event, a suitable period of accommodation to room temperature should always be provided for all film stored at reduced temperature before handling the film. 9 Inspection (see annex B) Regular inspections shall be made in order to recognize any deterioration as soon as p
29、ossible. If nitrate-base film is stored under the conditions given in clause 8, the film should be inspected at least once per year, and preferably every three months. The preferred method of inspection is accomplished by winding through the film so that the complete length is subjected to visual ex
30、amination. At the same time, when first opening the container the inspector should be alert for typical odours of deterioration, which approximate a mixture of fetid pungency with faint fumes of nitric acid. The very first indication of deterioration is an alteration of the image. Monochrome silver
31、images develop spots (which can be extensive) of reduced density that also acquire an iridescent sheen. Thereafter, with further deterioration, the typical odour develops, followed by physical changes including inter-layer adhesion plus weakening of the.emulsion and base. Alternatively, an analysis
32、of the relative degree of the nitrate-base deterioration can be performed. This analysis will only yield a qualitative measure of the film condition. The test should only be used to indicate the onset of irreversible deterioration of the nitrate base. See annex C for the test method using alizarin r
33、ed or Congo red and the evaluation of results. 10 Destruction Destruction shall be in accordance with any relevant laws and regulations. 3 IS0 10356:1996(E) Annex A IS0 (informative) Chemical stability of cellulose nitrate The chemical stability of cellulose nitrate used for the manufacture of nitra
34、te-base film is rather low. These films deteriorate slowly and continuously, even in a normal room climate. During deterioration, nitrogen oxide, nitrogen dioxide and other gases are liberated. In the presence of humidity, nitrogen dioxide forms nitric and nitrous acid which are strong oxidizing age
35、nts. If nitrogen dioxide cannot escape from the can, it reacts with cellulose nitrate and accelerates deterioration. This autocatalytic reaction causes problems because the degree of deterioration under all possible conditions is not proportional to the age of the film and often cannot be detected i
36、n a timely manner. Nitrate-base film which has been in good condition for years can deteriorate within a few months. Annex B (informative) IS0 10356:1996(E) Further information on storage and inspection The following five categories of decomposing nitrate-base film are described in reference 3 in an
37、nex D. a) Amber discolouration (single spots or large parts of the emulsion) with fading of the picture image. b) The emulsion becomes adhesive and film convoiutions tend to stick together during unrolling. c) Annular portions of the film rolls become soft, contain gas bubbles and emit a noxious odo
38、ur. d) The entire film roll is soft, its convolutions are welded into a single mass and frequently its surface is covered with a viscous froth. A strong noxious odour is given off. e) The film mass degenerates partially or entirely into a brownish acid powder. Deteriorated film in categories a) and
39、b) is photographically reproducible. In category c) only small portions may be reprintable. Films in categories d) and e) are useless and should be destroyed without further consideration. It should be noted that the maximum flammability-hazard occurs for categories b) and c). By the time the film r
40、eaches category e) it has lost virtually all of its nitrate groups, and its flammability has then been reduced to approximately that of the cellulose itself, i.e. comparable to the flammability of paper. The different deterioration speeds of nitrate-base film cannot be explained completely, although
41、 many factors are known which influence the stability. These are - inner stability and degree of purity of the cellulose nitrate; - keeping temperature - the deterioration speed doubles per 5 “C (9 “F) temperature increase; humidity content of the film; content of nitrogen oxides in the film; - acid
42、 gases from the air. Although fading of the image and the occurrence of spots can be caused by residua are no indications that these residues accelerate the deterioration of cellulose nitrate. A single piece of nitrate-base film burns with a bright yellow flame if sufficient air is a ailable. The ga
43、seous reaction processing chemicals, there products are colourless and not toxic. They consist mainly of nitrogen, carbon dioxide and water vapour. If there i s not e noug h air ava ilable for complete co Imb lustion, and this is n ormally burns wi th or W #it hou t flames and generates large a mo u
44、nts of thick yel low fumes. the case for film in rolls, the film WARNING - These fumes are very toxic and can give explosive mixtures with air. As an indication o f what gaseou S products can be a nticipated, condit ons for ther mal de compos iti on (refere nce 4 in annex D). Bl . gives those found
45、in one specific set of 5 IS0 10356:1996(E) IS0 Table B.1 Compound Concentration % WV) Nitrogen oxide Nitrogen dioxide and tetroxide Carbon monoxide Carbon dioxide Hydrogen Methane Hydrogen cyanide 1 to 8 7 to 9 48 to 59 21 to 25 1 to3 1 to 3 Traces During total combustion of nitrate-base film, betwe
46、en 0,2 m3 and 0,3 m3 of gas per kilogram of film are produced at room temperature and pressure. At flame temperature, the volume increases to about 2,5 m3 per kilogram of film. The calorific value of nitrate-base film corresponds to the value of wood (about 14 000 kJ/kg to 19 000 kJ/kg). Since nitra
47、te-base film burns 15 times faster than wood, the temperature increases much more rapidly. WARNING - A nitrate-base fire is nearly impossible to control and cannot be extinguished with normal fire-extinguishing agents. Annex C (informative) IS0 10356:1996(E) Method for determining the nitrate-base s
48、tability of motion-picture film using alizarin red C or Congo red C.l General The essence of the method lies in determining a time during which the colour under the action of nitric oxides evolved in heating a nitrate-base film sample. of an indicator paper will change Alizarin red C or Congo red ar
49、e used as an indicator. C.2 Preparation for analysis C.2.1 During visual examination of nitrate-base film materials, two samples of diameter 6 mm + 0,5 mm are cut out from each (part) roll. C.2.2 A solution in water, of alizarin red indicator (0,05 %) or of Congo red indicator (0,2 %), is prepared. C.2.3 The indicator paper is prepared as follows. Strips of filter paper are immersed indicator. The strips are then dried and stored in dark-glass pots with ground stoppers. in the solution in water of t
