unesco guidelines for the conservation of documents

8/10/2019 UNESCO Guidelines for the Conservation of Documents

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UNESCO Guidelines for the conservation of documents

Contents- Previous-Next

Part one: Processes and techniques and their application

2. Definitions, principles and standards3. Agents of deterioration and destruction4. Preservation5. Active conservation and restoration: Traditional materials6. Preservation and conservation of non-textual materials7. Substitution copying

2. Definitions, principles and standards

2.1 Definitions and Terminology

2.1.1 Preservation. This is a generic term for the totality of measures for

maintaining the integrity of documents and the information contained in them. Itincludes all the managerial and financial considerations, storage and

accommodation provisions, staffing levels, policies, techniques and methodsinvolved in safeguarding the holdings of archival institutions (see also definitions

in 21, 22, 24).

2.1.2 Conservation. This denotes the specific policies and practices involved inpreventing, delaying and reversing deterioration of and damage to documents,

including passive and active methods and techniques (21, 22, 24).

2.1.3 Restoration and repair. This embraces a wide range of active conservation

processes aimed at improving the physical condition of a damaged document and

returning it, as far as is practicable to its original state. These processes can rangefrom the repair of a torn leaf to the re-sewing and re-covering of a book, the

removal of a stain to the deacidification, buffering and re-sizing of a document (21,

22, 24). The restoration of archival documents never includes the replacement ofmissing text or other information (see 2.2.1(a) below).

2.1.4 Terminology. Unless otherwise indicated the terminology used in this studyis that of the ICA Dictionary (21) and Glossary (22).

2.2 Principles
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2.2.1 Basic principles of restoration and repair. The whole process of restoration

and repair may defeat its own object unless the true nature of archival materials

and the treatments which may be applied to them are fully understood and thosetreatments conform to certain basic principles:

a) No process may be used in restoration which would remove, diminish, falsify(by subtraction, alteration or addition) or obscure in any way the document's value

as evidence. This applies not only to the written text of the document but also to its

physical structure, when that itself has evidential value.

b) No process may be used which would in any way damage or weaken the

document.

2.2.2 From these stem three further principles:

a) As far as possible missing material should be replaced by material of the samekind, or with compatible, similar materials.

b) The nature and extent of any repair should be left unmistakeably evident.However, this does not mean that the repair should not be aesthetically similar to

the original.

c) Nothing should be done which cannot be undone without damage to thedocument. However, this does not mean that certain treatments, e.g. cleaning and

deacidification, which would never be reversed in practice, should not be usedwhen they are appropriate. A balance has to be struck between the possible effectsof any treatment and the durability of the document if it is left untreated and this

may justify in appropriate instances the use of irreversible processes, e.g.copolymerisation.

2.2.3 Documentation. It also follows that a proper record should be kept of allrestoration treatment (53). This should include, as a minimum:

a) information identifying the document;

b) the state of the document before treatment, including information about its

components (e.g. number of sheets);

c) information on any disassembly which is necessary before treatment can start;

d) the sequence of treatment processes and techniques used (during treatment this

should serve as a security control to ensure that documents are not lost or

misplaced);

e) the materials used, including any adhesives, sizes, etc. and the extent to whichoriginal materials have been reused;


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f) the identity of the conservator who has undertaken the work;

g) the dates of treatment.

2.2.4 The form which this document should take is a matter for local decision, butone common form is a combination of a chronological register which gives basic

details and a card file on which full details of the treatment are recorded for eachdocument, the cards being filed in accordance with the archival arrangement of the

documents. See Appendix D for suggested formats. Alternatively an abbreviatedtreatment summary on acid-free paper may be retained with the document. Wherea major restoration of an important document is undertaken, photographs of it

before, during and after treatment should be added to the record.

2.3 Standards

2.3.1 International standards. There are no international standards for archivalpreservation and conservation. However, the International Organisation forStandardization (ISO) has recently established a sub-committee of its technical

committee for information and documentation (ISO/TC 46/SC 10) which isconcerned with the physical characteristics of media for documents and has thefollowing terms of reference:

a) standardization of physical specifications and handling of any media used ininformation and documentation, including non-book materials;

b) conservation practices including environmental specifications, etc;

c) permanence of material specifications;

d) production aspects of documents, including binding, etc.

Its first area of concern will be with the permanence of paper to be used for booksand archives, and other work items are contemplated.

2.3.2 Pending the development of international standards, archivists andconservators are advised to follow the best practices set out in relevant RAMPstudies (included in Appendix E), in such national standards from other countriesas may exist (6, 27, 28) and in standards of practice and ethics promulgated by

professional conservation and archival bodies.

3. Agents of deterioration and destruction

3.1 Inherent Instability

3.1.1 Oxydation. This is a process of natural decay in air which affects all organicmaterials. If such materials are stored in good environmental conditions, the


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process is normally slow, but it is accelerated by oxidizing pollutants, such as

ozone (created in electrostatic copying processes), sulphur dioxide, nitrogen

dioxide and cleaning fluids. In paper it results in the breakdown of the cellulosefibre structure and the weakening of the paper. Its effects are unlikely to be

significant and are not easy to distinguish from those created by acid deterioration,which is more likely to be the prime cause of decay in archival documents.Oxidation is most noticeable in cellulose acetate still and motion picture film and

microfilm, where it becomes apparent in the form of 'redox blemishes' or 'red spot'.

3.1.2 Acid deterioration. Cellulose materials are also liable to decay throughcontamination by inherent acidic components, by acidic materials used in theirmanufacture and by atmospheric pollutants. Papers made from mechanical

groundwood pulp which has a high lignin content, or which have been sized with

alum rosin are especially liable to such deterioration. Deterioration will be

accelerated by certain external factors such as heat, humidity, light or chemicalpollution or by the use of acidic packing materials. The first visible evidence of

such deterioration may be a slight discolouration, which progresses in time throughyellow to brown. At the same time the paper loses its strength and eventually

becomes embrittled to the point where it crumbles when handled. The level ofacidity or alkalinity in a paper is measured by its pH value measured on a

logarithmic scale numbered from 0 to 14 with 7.0 as the neutral point; numbershigher than 7 denote alkalinity, while numbers lower than 7 denote acidity. pHmay be measured colourmetrically with certain chemical indicators (e.g. Merck

strips) or, more accurately, by potentiometric methods using electrodes.

3.1.3 Fugitive dyes. Certain pigments used in inks, waterbased paints, textile dyes,photographic dyes, etc. are fugitive and fade or change in time. These changes may

be accelerated by acidity, heat, moisture or light, but for some colour photographic

processes fading occurs even when prints or negatives are kept in the dark. Severalpigments, especially those in fountain pen inks and felt tip colours, are water

soluble and should be fixed prior to any treatments which require wetting.

3.1.4 Other chemical instabilities. A wide range of other chemical instabilities may

be encountered by archivists and conservators, e.g. fading or staining of badlyprocessed photographs, destructive deterioration of cellulose nitrate bases of old

still and motion picture film, hydrolysis of polyester film.

3.1.5 Electromagnetic deterioration. Most electromagnetic signals, e.g. on audio,video and computer tape, are subject to gradual loss of strength. They are,moreover, susceptible to deliberate or accidental deletion, distortion, print-through

and over-recording.

3.2 Environmental Agents


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on, paper and other organic components of documentary materials, weakening

them and often leaving disfiguring stains, which may obliterate information (67).

3.3.2 Insects. These also feed upon the organic components of documentary

materials: some on cellulose products e.g. paper); others on animal products e.g.certain adhesives, parchments, leathers). Book lice appear to be especially attractedto fungal growths and their attack on paper, etc. is a by-product of this.

3.3.3 Other animal pests. Rodents also may damage documents by feeding uponthem, using them as nesting materials or merely fouling them. Birds also may fouldocuments. Animal and bird excrement is not only unpleasant and corrosive but

itself provides food for fungi, micro-organisms and insects which may also attack

the documents.

3.4 Human Factors

3.4.1 Unintentional damage. Records may suffer from neglect, improper handlingand careless handling. Frequent use, no matter how careful, can itself lead to or

accelerate damage and deterioration. Photocopying without due care is a majorcontributor to damage. A recent international survey of archives and libraries

pointed to use as the most frequent cause of damage to documents and books (10).

Unintentional damage may occur from careless handling in retrieving and re-

shelving documents, from damage in transit within and between buildings or from

excessive display on exhibition. First-aid treatment of damaged documents by

unqualified persons with unsuitable materials e.g. pressure-sensitive tape('Scotchtape' or 'Sellotape')) can aggravate that damage.

3.4.2 Vandalism. This may involve tearing or cutting, writing on or marking

individual documents; disordering assemblies; or even arson.

3.4.3 Theft. The deliberate removal of documents, or extracts from documents, forpersonal gratification or monetary reward is, unfortunately, by no means unknown.

4. Preservation

4.1 Storage

4.1.1 Buildings. The provision of secure storage areas in which environmental

conditions can be stabilised by inherent construction or artificial means e.g.heating, dehumidifying or even full air-conditioning), which are well ventilatedwith good circulation of air to prevent the growth of fungi, from which pollution

and dust are excluded by air filtration, in which light levels are reduced e.g. by

using blinds to reduce natural light), in which fires can be immediately detectedand suppressed, and where risks of fire, flood and tempest are minimised is the

most effective single measure which the archivist can take to enhance the longevity


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of archival materials. So far as possible temperatures should be maintained as low

as practicable in the range 15-22 C and relative humidity as low as practicable

between 35% and 65%, preferably below 55%. Cycling even within these rangesshould be minimised if it cannot be prevented (8, 11, 16, 28, 33, 62, 75). The

weight bearing capacity of the flooring should be sufficiently strong to support afull load of documents.

4.1.2 Storage equipment. The storage equipment provided should be strong enough

to take the weight of documents; shelving should be of a proper size to support the

documents; racking and shelving should be chemically inert (non-corrodible) andfire-proof (i.e. metal not wood, baked enamelled surfaces properly and thoroughlycured not painted). Sufficient space (15 cm) should be left below the bottom

shelving to avoid damage from minor flooding and a similar space above the

contents of the top shelf to permit free circulation of air. The use of mobile

(compactus) shelving should not be considered if ventilation and air circulation is aproblem (28, 33).

4.1.3 Enclosures. The use of acid-free storage boxes and folders for loose papersand files and of boxes for bound volumes has been shown to extend the life of

documents stored within them and should be seriously considered. They provide agood level of protection against fire, flood, light, vermin, pollution and cycling ofenvironmental conditions in the storage area. Where acid-free boxes are not

available, boxing will still provide protection, but documents should be wrapped in

acid-free paper or folders as a protection against acid migration.

4.2 Good Housekeeping

4.2.1 Cleaning. The removal of dust and dirt from documents and their containerson their reception in the archives, and regular, preferably annual, cleaning

thereafter, will contribute to the maintenance of dust-free storage areas. Chemical

cleaning or bleaching should not be undertaken by non-conservation staff;materials should always be carefully tested before chemicals are applied to

ascertain that no harm will result as a consequence.

4.2.2 Removal of deleterious components. Corrodible metallic components, suchas staples, pins and paper clips should be removed. Files which are held on 'tags "

lengths of cord with solid ends which thread through the contents of files and

attach them to file covers) should have any tags with corrodible ends replaced byothers with plastic ends; files in pillar (or post) binders with corrodible pillars

should be removed from those binders and placed in new ones with inert pillars.Chemically active components with archival significance e.g. photographs, acidic

file covers) should be removed and stored separately or placed within inert

polyester sleeves. The removal of pressure-sensitive tape requires the careful use

of solvents and should not be attempted by non-conservation staff.


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4.2.3 Flattening. Folded papers should be opened and held flat by pressing or by

humidification and tying between acid-free boards after interleaving with white

blotting paper, never by the direct application of a domestic laundry iron.

4.2.4 Packing. Any repacking should be in acid-free materials. Boxing, as in 4.1.3above, is the best means of packing, but where this is not feasible wrapping inacid-free folders or wrappers tied with undyed broad cotton tape (not string or

cord) may be recommended.

4.2.5 Handling. Procedures for the careful handling of documents by staff andusers should be introduced and enforced. These will include:

a) provision of archival trolleys which support documents adequately and are

manoeuverable;

b) avoiding stacking documents on trolleys, desks, floors, etc;

c) providing adequate working surfaces for staff and users and, where necessary,properly

constructed book-rests or cradles; and

d) controlling the handling of documents when being photocopied.

4.2.6 Inspection. Storage areas should be inspected regularly to ensure that storageand environmental conditions are adequate and that there has been no infestationby fungi, micro-organisms, insects or vermin.

4.3 Pest Control

4.3.1 Treatment of premises. Where fungi, micro-organisms, insects or vermin arean inherent problem within the storage areas, regular treatment with appropriate

substances is essential (71).

4.3.2 Routine treatment of new accessions. Where fungi, micro-organisms orinsects are an endemic environmental problem, it is desirable to eliminate them

before documents are placed in storage by an appropriate method of disinfestation.

However, this will be ineffective if the area into which they will subsequently be

placed is already infested or provides conditions which encourage a recurrence of

the problem.

4.3.3 Treatment of infestations. Where an infestation of fungi, micro-organisms,insects or vermin is discovered, immediate steps should be taken to treat theaffected documents by cleaning, disinfestation, etc. to clean and disinfect the area

(aerosol sprays should not be used - they will spread the infestation) and toeradicate the cause of the infestation, e.g. improving the environment (i.e. lowering


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the temperature and relative humidity), repairing broken windows or damaged

screens. Food and drink should never be brought into storage areas (or, ideally,

into the archive). Documents should not be replaced in the area until the source ofthe infestation has been eliminated.

4.3.4 Methods of treatment. Considerable uncertainty exists as to the best methodsof disinfestation. Those which have been employed are:

a) fumigation, which requires a special fumigation chamber and appropriatechemicals; thymol, long a preferred chemical, is now considered to be of limitedeffectiveness and ethylene oxide is explosive when mixed with air and requires a

properly designed and maintained vacuum chamber for its use and very careful

handling (33); also its reaction and decomposition produces by-products which areboth toxic and injurious to certain documentary materials;

b) freezing in a modified domestic freezer to -18C will kill insects, their larvae

and their eggs, but not all fungi;

c) radiation has also been tested in the laboratory, but the necessary facilities areunlikely to be available to most archival institutions (57, 64);

d) environmental conditions which do not encourage fungi and insects are the most

effective single contribution to eliminating them from storage areas.

4.3.5 Health and safety. Effective disinfestation treatments are in general harmfulalso to humans and should, therefore, be applied only by properly trained

personnel using proper equipment under conditions prescribed by law or by

manufacturers' recommendations (see also section 10.7 below).

5. Active conservation and restoration: Traditional materials

5.1 Paper

5.1.1 Nature and properties. Paper is an organic material of which the main

component is cellulose. In papers made before the middle of the nineteenth centurythis cellulose is mainly derived from cotton and linen, although other vegetable

fibres might be used, and the fibres are long and relatively stable. Such 'rag' papermay be 'hand-made' or 'mould-made'. From the nineteenth century wood pulp was

increasingly used and paper making became industrialized. The paper thusproduced is usually known as 'machine-made' (it is also possible to obtainmachine-made paper made from cotton pulp). It may have been processed in a

variety of ways and contain varying quantities of lignin. Although it is possible to

make wood pulp paper which is long lasting, the cellulose fibres tend to be shorterand the paper may be more acidic than paper made in the traditional way and hence

much less permanent. Mechanical groundwood papers e.g. those used for


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newsprint) in particular are chemically unstable and rapidly discolour, going

through phases of yellow to dark brown, and become embrittled to the point of

disintegration under the influence of acid deterioration, accelerated by suchenvironmental influences as light, heat, humidity and atmospheric pollution.

5.1.2 To give paper strength and to enable it to receive writing ink withoutfeathering the basic cellulose is treated with sizes and fillers. In early papers the

size was usually gelatine, an animal substance which may lose some of its body in

time but does not break down so as to damage the paper. However, in more

modern papers the sizing agent is often alum rosin, which is acidic and willcontribute to the deterioration of an already acidic paper. Fillers are usually derivedfrom china clay or chalk and are, therefore, often alkaline and tend to counter any

acidity in the paper or atmosphere. Since papers used as supports for manuscript

and typescript inks often have a high filler content, archival papers are often less

seriously affected by acid deterioration than library books, though duplicated andprinted documents, especially newsprint, and even manuscript and typescript

records on inferior paper may be seriously affected.

5.1.3 Deacidification. Traditional paper repair will not of itself remedy the effects

of acid deterioration. This can only be done by neutralising the acid and building inan alkaline buffer by chemical means (excessive alkalinity may also damage paperand a pH level of more than 9.0 should not be sought). Deacidification should not

be undertaken before inks and pigments have been tested for fastness in the

substance to be used and, if they are not fast, have been fixed. A number of

techniques of deacidification have been developed:

a) aqueous deacidification, in which affected paper is immersed in (fragile

documents should be supported), or brushed with, an alkaline solution orsuspension (magnesium bicarbonate is generally regarded as the most effective)until the acidity has been neutralised and the pH value has been raised to between

7.5 and 9.0; after treatment any necessary repair is then undertaken and the paper is

re-sized and pressed; this method is tried and tested, but may not be safe for very

fragile documents; it is also a very slow process;

b) spirit deacidification is similar to aqueous deacidification except that the alkaliis dissolved or suspended in an organic solvent; it can be applied in spray form,which speeds up the process, though it may not be as effective as immersion;

c) vapour-phase deacidification employs chemicals in gaseous forms to neutralise

the acid; this is potentially easier to use and offers greater productivity than eitherof the immersion processes, but unfortunately most of the gases which have been

used are poisonous or otherwise injurious to health and this system is not now

recommended;


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d) mass deacidification methods are being developed in a number of countries but

are still in the experimental or developmental stage. All require expensive plant;

some require the use of a vacuum chamber, which may be safe for bound volumesbut not always for loose sheets; others use chemicals which require careful

handling if they are not to be a threat to health and safety. Most are likely to becost-effective only where a high volume of work can be foreseen (42).

5.1.4 Traditional paper repair. Where paper has been damaged, traditional repair

techniques (see 5 for a more detailed treatment of these) require the use of a good

quality, new, mould-made paper of equal weight and similar colour to the original.This paper is used in such a way that its 'grain' runs parallel to the 'grain' in theoriginal paper. Where it will be abutted on to the old paper, it is 'needled' or scored

to outline the precise shape required and then carefully torn rather than cut as this

enables the fibres of the old and new to interweave. An alternative technique uses

Japanese tissue rather than standard paper. The principle types of repair are:

a) mending, in which tears in the paper are pasted together;

b) infilling, in which pieces of the new paper are carefully made to match holes in

the original, using a light-box to draw the precise shapes in the new paper beforetearing, and are then pasted in place;

c) framing, which is the reverse process in which a frame is made to surround a

sheet of paper which has been damaged at the edges;

d) backing, in which a new sheet is pasted on the reverse of the old sheet; whereholes or damage to the edges exist backing should be used in association withinfilling or framing, otherwise the differing thickness of paper will create a

weakness in the repair; this technique can only be used when there is no text on the

reverse of the original sheet, although when there is only a small amount of text,backing may be permissible provided that 'windows' are provided to expose that

text or thin, transparent Japanese tissue is used.

5.1.5 Traditionally a vegetable (rice or wheat starch) paste (sometimes with

additives to combat fungal growth and deter pests - these additives should not beotherwise deleterious to the document) has been used for paper repair, but modernsynthetic pastes are now sometimes used, though they should be used with great

caution and only after careful testing both of their chemical stability and of the

permanence of their adhesive qualities.

5.1.6 Paper repair using the hand-made paper technique is usually undertaken withthe original and repair paper damp; with Japanese tissue it is usually done with the

paper dry. The former method will remove some of the original size and after the

repair has been completed each individual sheet may be re-sized and dried loose ona frame (pressing will cause the re-sized sheets to stick together). Large documents


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may be dried lightly pasted to nylon sheeting on a melamine laminate surface,

which may be a vertical or near-vertical wall board. They will strip away from the

nylon when dry.

5.1.7 Lamination. The earliest, and still the most common, mass treatment systemfor repairing paper documents is lamination. This may be undertaken by semi-skilled staff after a minimum of training. However, it adds to the bulk of a

document and it contradicts to some extent two of the principles of repair: that like

or compatible materials should be used in repair, and that the repair should be

readily reversible. It may be of two kinds:

a) machine lamination, in which the sheet of paper to be repaired is placed between

two layers of tissue coated with a thermoplastic adhesive (alternatively separatesheets of the thermoplastic adhesive may be placed between the document and two

sheets of uncoated tissue), and heat and pressure is applied to cause the sandwichto adhere (thus contradicting another principle of repair: that nothing should bedone which is potentially damaging to the document); the Barrow process is not

recommended as it may damage the documents to which it is applied; certainlysome early examples of this treatment have deteriorated badly, although it appears

that in at least some cases it is untreated inherent acidity of the paper, acceleratedby the treatment, which has led to this deterioration; the basic rule for machinelamination must be, therefore, always test for acidity first and deacidify if

necessary before lamination; the Postlip-Duplex (or Langwell) process uses lower

heats and pressures and the tissue which it uses is a cellulose fibre and can be

removed if necessary, but sufficient doubt about the life of laminated paper existsfor the process to be recommended only for low value, high use documents (seeTable One after 8.3.2 below); automatic and semiautomatic machines are available,

which increase productivity;

b) manual lamination is a similar process in which heat is not applied, two main

variations are employed:

(i) florentine repair, in which the sandwich is Japanese tissue, a very fine,translucent paper, and the adhesive is a standard paper repair paste; this type of

repair may also be undertaken with machine lamination; and

(ii) spirit lamination, a process developed at the National Archives of India in

Delhi, but not widely accepted, in which the sandwich is cellulose acetate film andtissue paper, adhesion being provided from the chemical action of acetone which is

applied evenly over the surface with a non-linting cloth (15).

5.1.8 Encapsulation. As an alternative to lamination which will support a documentwithout the application of heat, pressure or adhesive, the technique of

encapsulation has been developed. Here the document is encased in an envelope ofinert transparent polyester film e.g. 'Mylar'). As with lamination it is necessary to


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deacidify before encapsulation. Ready-made envelopes may be used for less fragile

documents, but for weak and friable items it is necessary to build up the envelope

around the document. Early encapsulation techniques made use of double-sidedadhesive tape, but it was found that there was a potential risk of the document

slipping into the adhesive. Heat sealing also placed the document at risk (thoughnewer systems used in the USA appear to be safe), but ultrasonic welding appearsto provide a safe sealing system. A cheaper alternative is machine-sewing the

polyester sheets together with a zigzag stitch. Only a minimum of skill and trainingis required to undertake this process, which may take longer than lamination and

adds more to the bulk of the document. Another major problem is the tendency for

electrostatic attraction to lift friable or flaking inks and pigments and for these toadhere to the polyester film; encapsulation should not be used for such materials.Encapsulation may be used to preserve archival materials other than paper e.g.

photographs, textiles) and to isolate degrading materials interfiled with other

documents.

5.1.9 Leaf-casting. This method of repair employs the technique of making newpaper to fill in holes in the original document. The document is placed over a fine

mesh and immersed in water to which a slurry of cellulose (usually made fromcotton [inters) is added; a vacuum is created below the mesh, drawing off the water

through the holes in the document and leaving the slurry (which dries to form newpaper) held by the mesh and making good the holes. A variety of leaf-castingequipment is available, ranging from small manual machines to large automatic,

and even continuous, ones. The disadvantage of this process used on its own is that

it wily fill holes, but not repair tears or strengthen weak paper (although resizingcan be accomplished while leaf-casting). Hence, documents may require further

treatment - e.g. lamination or encapsulation - to make them suitable for handling.Moreover, since it is a wet process, it can only be used with non-water-soluble inks

and pigments. However, it can be used conveniently with aqueous deacidification.

A considerable amount of skill and experience and careful calculation of the extentof the damage and the quantity of slurry required (these calculations may be done

by sensing equipment or by hand; they are easier to make when book leaves and

documents on paper of the same size are to be repaired) are necessary to achieve

good results (i.e. where the replacement paper is exactly the same thickness as thatof the document), and even with the expensive continuous machines, productivityis not, therefore, very high.

5.1.10 Paper splitting. The technique of paper splitting is an old one, which has

recently been revived, especially in Eastern Europe. In this treatment weak or

damaged paper sheets which have text upon both sides and which cannot bebacked are split laterally to form two single-sided sheets, between which a

strengthening sheet is inserted. This is a skilled process, which requires trainingand experience, and it is not possible, therefore, to achieve high productivity;

though it is quicker than traditional paper repair.


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5.1.11 Paper strengthening. Experiments are being made with systems for

strengthening weak papers by impregnating them with monomers and bombarding

them with weak gamma-rays to create polymers which are chemically attached tothe paper. None of these systems of copolymerisation has yet been proved or

developed beyond the prototype stage (74).

5.2 Bindings

5.2.1 Restoration of bindings. The repair or replacement of bindings is rarely cost-effective unless the original binding has historical, aesthetic or other intrinsic valueand interest or the document which it encases is of high value and interest. Where

the repair or replacement of a binding appears justified on such grounds, the old

binding should be disassembled only so far as is necessary to repair any damage toits contents, and restored in exactly the same style and materials as the original.

Such work requires high levels of skill and experience, far beyond those of thestandard library bindery. It also takes considerable time and cannot be rushed.

5.2.2 Binding. The traditional method of securing loose papers to make them easier

to handle and to protect them against theft or misplacement is to bind them into

volumes. Since such papers rarely come in identical sizes and in neat gatheringslike the sheets of printed books, here also a level of skills and experience higher

than those of the standard library bindery is required. Special techniques, such aspacking to make up for smaller sized sheets and to assist the volume to open

properly, have to be learned. Cropping pages to provide neat edges should never

take place. This work is time consuming and labour intensive. Where adequatemargins have not been left, especially on the reverse sides, the text may disappear

into the gutter and be difficult to read. An alternative method of perfect binding

using modern adhesives and standard cases has been employed in some archives.This can be semi-mechanical and does not require highly skilled operators. It is,however, doubtful whether the volumes so created will stand up to the test of time

or frequent handling for consultation and copying. In China and Japan a style of

binding is pratised in which writing is on one side of each sheet of paper; this is

then folded back and volumes are made up by threading through the margins of the

doubled sheets.

5.2.3 Guarding and filing. This technique makes use of guards, or paper strips, ofthe same weight as the individual papers which constitute the assembly. Each

paper is pasted by means of a slight overlap to its guard and the guards are thenaligned, drilled and laced between pre-cut boards. Special care has to be taken to

balance smaller sized papers to give an even thickness to the finished file.

Alternatively a guard may be attached in machine-lamination processes by abutting

it to the paper and overlapping the laminating tissue on to the guard. Guarding andfiling, except in the laminating process, requires some skill and experience and is

labour intensive, though less time-consuming than binding proper. It has the


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advantages over binding of enabling the pages to open completely clear of the

gutter and of permitting the volume to be taken apart easily again if necessary.

5.2.4 Pillar binding. When documents are encapsulated, an adequate margin of

polyester may be left which can be drilled and the encapsulated documents madeup into assemblies within pillar (post) bindings.

5.3 Parchment and Vellum

5.3.1 Nature and properties. Parchment is made from the skin of animals (usually

sheep or goats) prepared in a special way so that it can be written on with ink. It is

found extensively among the medieval archives of Western Europe, but it occurs atlater dates and more widespread geographically for the recording of especially

formal and solemn documents. Parchment has a 'grain', arising from the

rearrangement of the natural fibres as a result of tension applied during processing,and the 'hair' and 'flesh' sides have differing characteristics. Some parchments are

split in the interest of economy or suppleness. Vellum (originally calf skin - thereis no separate word in many languages) is of a heavier weight and was used for

important manuscripts and documents and for bindings and other types of cover.

5.3.2 Traditional parchment repair. The techniques of repairing damaged

parchment documents are similar to those for paper described in 5.1.4 above. New

parchment of a similar thickness and colour, with a similar 'grain' and with 'hair'

and 'flesh' sides matching should be used to repair damaged documents. The main

differences from repairing paper documents are that parchment has to be cut, nottorn, and the edges on the flesh side carefully pared to provide a slight overlap, and

that the repair is performed with the parchment dry (though it may be necessary torehumidify to 55% RH before treatment if the parchment has become too dry). Theskills and experience required are equal to those needed for traditional paper repair

and the process is labour intensive and time consuming.

5.3.3 Strengthening parchment documents. Where parchment documents need tobe strengthened, they may be backed with new parchment, if the reverse contains

no text. Where it does contain text a traditional strengthening material has been

fine silk gauze (an animal product) which is pasted over the parchment. Substantialloss of legibility may occur as a consequence. An alternative traditional substance

is goldbeaters' skin (a fish swim bladder product). A newer technique uses a

covering of reconstituted collagen (another animal product, mainly used to makesausage skins). This is cheaper than goldbeaters' skin and blends better with the

parchment than silk and causes less loss of legibility.

5.4 Other Traditional Support Materials

In addition to paper and parchment many other materials have been used atdifferent times and by different societies as a support for written information.


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These include papyrus, birch bark, palm leaves, wood, ivory, clay and stone. The

conservation of such materials is as highly specialised as is that of paper,

parchment and bindings, and should not be attempted without proper training andexperience. Advice on the conservation of traditional materials is likely to exist

still within their country of origin, often within the museum service, if not moregenerally.

5.5 Seals

The use of seals to authenticate documents is common to many periods andsocieties. They vary in form (pendant - double or single sided, applied, stamped)

and materials (lead, wax, shellac, ink). The repair of pendant and applied seals is

highly skilled work, not to be undertaken by the inexperienced. Where thenecessary skills are not available, the best treatment is to pack the seals carefully in

cellulose wadding to prevent further damage and to restrict further handling,though care should be taken to avoid detaching them from the documents. Stampedseals may often use inks or pigments which are water-soluble and special care

should be taken, therefore, when subjecting the documents on which they occur totreatments which involve wetting.

6. Preservation and conservation of non-textual materials

6.1 Still Photographs

6.1.1 Nature and properties. Although photography has been around for almost a

century and a half, it is only recently that, outside a few specialist photographic

collections, concern has been shown for the preservation of photographs,especially those which occur among archives (2, 25, 29). Photographs presentspecial problems because they are complex objects, which have in common only

that each is composed of two or more elements, including a support or base (which

may be of many different substances), a chemically active ingredient (usuallymetallic silver in the case of black and white photographs) which reacts to light to

form the image and a binder to bind the two together (except in collotypes anddaguerrotypes). Each of these elements may react differently not only to

environmental conditions, chemical pollution or handling but also to attempts attheir conservation. Active conservation is, therefore, a highly skilled operationwhich should only be undertaken by those trained and experienced both in

recognising the specific photographic processes involved and in their respectivetreatments. In general the safest treatment for photographic records is to pack themindividually in chemically inert wrappers (not only acid-free but also sulphur- and

peroxide-free - glassine envelopes are not now recommended) or encapsulate them

in polyester film, and preserve them in the dark in optimum environmental


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conditions (the lower the temperature the better; relative humidity should be

between 30% and 50%).

6.1.2 Photographic negatives. These may be on a variety of transparent supports,

the chief of which are glass, cellulose acetate and polyester (poly(ethylene-terephthalate)). These supports are of varying stability (see 3.1.1 and 3.1.4 above).Damage to photographic negatives is most likely to occur from breakage in the

case of glass negatives; from damage to or distortion of the emulsion layer arising

from the differing responses of support and emulsion to dimensional changes

resulting from cycling of environmental conditions, which can cause the emulsionand image to crack or even to separate from the support; or from chemical damageto the image as a result of poor initial processing, subsequent chemical pollution

from the environment, or migration from wrappers or other substances with which

they have been in contact or to which they have been close in storage. Still

photographic negatives on a cellulose nitrate base (which is chemically unstableand highly inflammable) are less common than motion pictures on such a base.

Photographic negatives on a paper support may also be found. Active conservationtreatment of photographic negatives, such as chemical re-processing or floating

emulsion and image from a damaged support to a new one, should only beattempted by those who are professionally competent to do so.

6.1.3 Photographic positives. These are most likely to use paper as their support,

but a variety of other supports may be found, such as metal in several early

processes, and glass for lantern slides. As with photographic negatives damage is

most likely to occur from damage to or distortion of the emulsion and image, orfrom chemical damage to the image, often caused by poor processing, atmospheric

pollution or impurities either in the paper support or, more commonly, in mounts

or photographic albums, or by other materials (e.g. newsprint) stored in association

with them or enclosures (envelopes, boxes, etc) of poor quality materials. Removalfrom mounts and albums, where this is possible without risk of damage to the

photographs or loss of evidential value, and separation from associated materials

may arrest, though it cannot reverse (but see 2), chemical deterioration. (It isaxiomatic that where photographs are physically removed from associated

materials which themselves form part of the record, the intellectual links betweenthe two must be retained by means of cross-references in lists or inventories.)

Active treatment should be undertaken only when skilled photographic

conservators are available.

6.1.4 Colour photographs. These come in the form of negatives, positive printsmade from them, 'direct' positive transparencies/slides, and 'direct' positive prints('Polaroid'). The light sensitive dyes which record the image are much less stable

than the silver salts used in black and white photographs and it is crucial that they

be stored in a stable environment, ideally at a low temperature of not more than 5

C with a stable relative humidity in the range 30-50%. Active conservationtreatment of damaged or deteriorating colour photographs is generally virtually


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impossible and duplication may be the only option for rapidly deteriorating

examples.

6.1.5 Microforms. These are a version of still photographs in which a series of

images is held on a transparent support (cellulose acetate or polyester - see 3.1.1and 3.1.4 above for stability problems) in roll (microfilm) or sheet (microfiche)form. Some early microfilm may be on motion picture cellulose nitrate stock, from

which it should be copied and the original disposed of (see 6.2.1 below). The

image in all early microforms and in modern archival microforms is formed in a

silver-gelatin emulsion, which is liable to the same kinds of damage ordeterioration as other silver-salt photographs. Diazo, vesicular andelectrophotographic ('erasable') microforms are now common as duplicates; they

tend to react adversely to high levels of light and are not recommended for long-

term preservation. Treatment of microforms is usually confined to the replacement

of metallic spools or poor quality, unstable containers by inert ones, followed bystorage in the recommended environmental conditions (26) and apart from paper

based materials which may give off peroxide fumes. Careful washing of dirty orsticky microforms may also be undertaken, but chemical treatment is not

recommended.

6.1.6 Office copies. There have been many and varied processes for producingoffice copies either direct from the originals or by printing from microform copies.

Of these the earliest was the mimeograph, characterised by the very poor quality of

the paper supports and the fugitive dyes in the inks. The earliest copy process was

the 'photostat' (a term often used loosely and incorrectly for all photocopyingprocesses), which was produced by a photographic process and, if properlyprocessed and stored, created a reasonably permanent copy. Unfortunately most

were not properly processed. The latest, the electrostatic or xerographic copy

(sometimes known by the trade name 'Xerox'), can also be virtually permanent ifthe machine in which it has been created was properly serviced, the toner was

correctly formulated and fused and the paper is of permanent quality. However,

between the two there have been a vast number of other processes, e.g. thermofax,verifax, which have produced copies which are very short lived because the quality

of the materials is poor, image fixing is poor and the coated paper used is sensitiveto light or heat. The only way of preserving the texts of such copies is to recopy

them by a process which produces a more permanent copy (69). Office copiers

which reproduce colour have recently been introduced. The archival permanenceof their products is uncertain.

6.2 Moving Images

6.2.1 Motion pictures. Motion pictures (also called movies or cinematograph films)present all the problems encountered with still photographs, to which should be

added, from the 1930s onwards, those created by soundtracks. Black and white 35mm motion pictures made before 1951 are likely to be on a cellulose nitrate base


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and, therefore, highly inflammable or even explosive. They require special vaults

for their storage and the only effective treatment is to copy them on to safety stock

and dispose of the originals. Later 35 mm films on cellulose acetate ('safety') stockand all 16 mm films (on 'safety' stock) present fewer problems. Early colour film

('Technicolor') is reasonably stable, but new colour processes extensively usedbetween 1950 and 1970 are less permanent, and require special low temperaturestorage. Physical conservation treatment of motion pictures is impractical in all but

a few rare and important cases. The only solution to damage or deterioration isproper handling and storage to arrest it or, if it has gone too far, copying (35, 45).

6.2.2 Video recordings. These are a new form of moving image, with sound,created by recording electrical charges on a magnetic tape. They are mainly at risk

from wear, from damage in inadequately maintained machinery or from unsuitable

environmental conditions which may cause the separation of the electromagnetic

recording medium, the polyester base and the proprietary binder (usually polyesterurethane, which becomes sticky at high temperatures and relative humidities)

which holds them together. There is also some evidence that the electromagneticsignals fade over time and may be affected by external electromagnetic

interference. Preservation in a proper environment and careful handling areessential, failing which the only preservation measure is copying, though this can

present problems if the original recording equipment is obsolete and unavailable.

6.3 Sound Recordings

6.3.1 Audio discs. Early sound recordings are to be found on wax or shellac drums,wax and metal discs (pressing masters) also may sometimes find their way to the

archives; but the most usual form of sound recording until very recently was the

disc, originally in fragile shellac but since the 1950s more often in plastic, which isless fragile, but liable to scratch and warp. Sizes, playing speeds and methods ofrecording (acoustic and electrical) vary but the basic technology is generally the

same. The materials are generally very stable (though 'leaking' of the plasticizer in

discs is not uncommon), but physical damage from careless handling (scratching or

breakage), poor quality or damaged pickups, excessive playing (wear or

scratching) or bad storage (warping) is common. Copying is the only practicablepreservation measure if the machinery is still available to 'play' the original (35).

6.3.2 Audio tapes. These are polyester tapes carrying a magnetizeable coating held

together by a proprietary binder. The magnetic layer receives and holds anelectrical charge which can be read back to re-create the sound. Variations are to

be found in the number of tracks per tape and in the recording/playback speeds.

The problems are the same as for video recordings (see 6.2.2) and copying, where

equipment is still available, is the only practicable preservation measure.

6.4 Machine-Readable Records


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6.4.1 Magnetic media. The well established means of recording computer data is a

magnetic medium, which may be in tape or disc form, with characteristics which

are similar to those of video recordings (see 6.2.2) and audio tape (see 6.3.2). Thepreservation of such media requires proper storage, careful handling and, if all else

fails, regular copying.

6.4.2 Optical discs. A more recent development is in the use of lasers to write and

read to specially prepared discs to record digitally encoded data whether those be

computer records, video pictures or audio sounds. The process is still at the

development stage and there are no standards for recording and replaying devices,but it is a highly compact medium which may at least provide a longer-termstorage medium for digitally encoded data than magnetic video, audio or computer

tape or magnetic disc.

7. Substitution copying

7.1 Purpose

7.1 1 Alternative to conservation treatment. The substitution of a copy (or .surrogate) for an original record which is damaged or decayed or which will

predictably deteriorate may be the only solution when restoration treatment has a

low priority or is impractical on account of cost, lack of technical expertise or

absence of a suitable treatment. The original thereafter can be:

(a) enclosed carefully in neutral wrappings and placed in secure storage inoptimum environmental conditions until a cost-effective treatment is available: thisis most appropriate for damaged documents but may also be appropriate fordeteriorating documents which are not yet at the stage of complete decay and

where the rate of deterioration can be arrested or reduced by proper storage;

(b) left to continue its deterioration, but with the hope that a cost-effectivetreatment may be developed before it decays completely; or

(c) destroyed - this is not an option which an archivist will readily adopt, but it may

sometimes be the only sensible course; in many cases it will be the unavoidableoutcome of option (b).

7.1.2 After conservation treatment. In other cases it may be necessary both to treatthe original record and to provide a substitute copy for reference use. This may be

because either:

(a) the record has a high intrinsic value and merits conservation treatment - in this

case the purpose of the substitute is to provide a copy for consultation, thuspreventing further or renewed damage or deterioration of the repaired original; or


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(b) the record has a high informational value but is so badly damaged that a copy

cannot be made until at least some repair treatment has been undertaken.

7.1.3 To prevent damage requiring conservation treatment. Here the substitution is

a preventive measure to remove the risk of damage to records which may be fragilebut not deteriorating, in a sound condition but likely to be heavily used andhandled or of very high intrinsic value. In such cases the originals should be

retained and stored in proper environmental conditions.

7.2 Types of Substitutes

7.2.1 Facsimiles. For an individual record with a high intrinsic value (e.g. an earlyilluminated manuscript, the national constitution or a holograph letter from a

famous historical personage) a good quality facsimile is the best substitute.

However, such facsimiles require a good, if not a special, camera and facilities forproducing high quality colour photographs or even, if multiple copies are to be

produced, for colour printing. They are, therefore, usually expensive and oftenrequire the document to be taken to a photographic studio where environmental

conditions and document handling techniques will need to be monitored carefully.

If the original is a bound volume, it may be necessary to disbind the volume andseparate the sheets, even where that is not essential for the conservation treatment,

to obtain the best results. Any negatives or printing masters should be kept inoptimum environmental conditions to ensure that the copying once done will never

have to be repeated.

7.2.2 Photographs. Where the expense of a full-colour facsimile is not justified, a

good black and white photograph may be sufficient, especially as a means ofproviding reference copies of photographs. The print need not be actual size wherethe original is still being preserved and the purpose of the print is to save damage

or deterioration from handling. Colour transparencies may be a suitable means of

producing reference copies of records in which colour is an important element,such as maps and plans, posters, topographical sketches. It is important that the

negatives or other masters be carefully preserved and catalogued to preventunnecessary recopying.

7.2.3 Electrostatic Copies. This is a cheaper method of providing black and white

same-size copies than photography. It is the best way of replacing deteriorating

non-permanent copies or other individual items in modern files. Continuous printfrom microfilm can be filed (in the sense of 5.2.3) between boards to produce

substitute volumes. Where direct copies are required, 'permanent' paper should beused, the machine should be properly maintained and clean, and the toner should

be of the kind, and be used as, recommended by the manufacturer (69). It is

important to instruct staff carefully in the careful handling of documents during

copying. In general copying of bound volumes should be avoided since theapplication of pressure is likely to result in damage to both binding and paper.


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7.2.4 Microforms. The cheapest method of providing substitutes is microcopying,

in the form of roll microfilm or microfiche. Not only is it the cheapest form of

substitution; it is also cheaper than any form of active conservation. The masternegative, which should be of the silver-gelatin type on polyester film and be

processed in conformity with international processing standards, should be storedin accordance with international preservation standards and should never be usedas a viewing copy, but only to produce duplicates to serve as intermediate masters

or viewing copies (4, 18). Colour microforms may be used for viewing copies ofcoloured materials which would be damaged by excessive handling, but they are

not permanent and should not be relied upon as substitutes for deteriorating

originals.

7.2.5 Electronic image capture. This new technique is based upon a combination of

photo-electric, laser and computer technologies which enables a document to be

scanned as a matrix and the black/white or red/blue/green characteristics of thevery small segments of that matrix ('pixels' = picture elements) to be reduced to an

electronic code, which can be stored on a magnetic medium or optical disc andviewed on a display screen or printed out. It is also possible, using this technique,

to enhance the quality of faded or incomplete images, and it has been used in thisway to restore deteriorating still and motion pictures and to replace faded or

stained original paper documents.

7.2.6 Information transfer. When it is only the information contained in the original

record and not the original support/carrier of that record which is important, it is

justifiable to transfer that information by copying. When the support isdeteriorating copying may be the only way of preserving the information. To someextent all the processes described above are forms of information transfer, but they

are means of preserving individual items, or series of items, which have been

found to be damaged or deteriorating or to be at risk of damage or deteriorationfrom excessive use. Some forms of record are known to have a limited life and

should always be recopied on transfer to the archives. One option is copying on to

the same medium (in which case further copying will be necessary in due course),especially for audio, video and computer recordings on magnetic tapes, which

should at least be transferred to fresh tapes which have been evaluated and testedand which are of 'archival' quality (this does not mean 'permanent' in this context).

Transfer to a different version of the same medium tea audio cassettes to open reel

magnetic audio tape, 'floppy discs' to magnetic computer tape, nitrate film to safetyfilm), or even to a different medium (e.g. to optical disc) should also be

considered. Records in other formats for which the risk of damage is high may also

be copied automatically on transfer to provide a copy for back-up and use (e.g.gramophone discs to audio tape, glass photographic negatives to film negatives).

Part two: Planning, staffing and equipping a preservation

and conservation service


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8. Establishing a preservation and conservation programme9. Workshop accommodation and services10. Staffing11. Equipment and materials12. Planning and co-ordination

8. Establishing a preservation and conservation programme

8.1 Evaluating Needs

8.1.1 Preservation and conservation surveys. The most effective way of tackling

preservation and conservation problems is to establish a planned conservationprogramme based upon a systematic survey of buildings and holdings. Guidance

on the conduct of such a survey is given in a separate RAMP study (13) and willnot be repeated in detail here.

8.1.2 Levels of investigation. The survey should identify preservation and

conservation problems at the following levels:

a) those affecting the building as a whole (e.g. unsatisfactory environmentalconditions);

b) those affecting a specific area of the building (e.g. an insect or mould

infestation);

c) those affecting the whole of a series of records (e.g. acidic deterioration arising

from their component materials);

d) those affecting an individual item (e.g. damage caused by excessive or carelesshandling).

It is usually not feasible to conduct an inspection of every item, but each series

should be sampled to identify not only general problems but also any high

incidence of individual problems which would justify an item-by-item inspection.

8.1.3 Continuous assessment. It should not be assumed that the conservationconditions in an archive will remain static and the survey of the building should be

repeated annually and that of the holdings at intervals of not more than every tenyears, to identify new or recurrent problems and to assess the progress ofdeterioration of documents which it has not been feasible to treat in the intervals

between surveys. In addition the conservation condition of each new accession

should be noted and integrated into the programme. Items produced for

consultation should also be inspected as a matter of routine to identify any
http://www.unesco.org/webworld/ramp/html/r8904e/r8904e05.htm#8.%20Establishing%20a%20preservation%20and%20conservation%20programmehttp://www.unesco.org/webworld/ramp/html/r8904e/r8904e05.htm#8.%20Establishing%20a%20preservation%20and%20conservation%20programmehttp://www.unesco.org/webworld/ramp/html/r8904e/r8904e05.htm#9.%20Workshop%20accommodation%20and%20serviceshttp://www.unesco.org/webworld/ramp/html/r8904e/r8904e05.htm#9.%20Workshop%20accommodation%20and%20serviceshttp://www.unesco.org/webworld/ramp/html/r8904e/r8904e05.htm#10.%20Staffinghttp://www.unesco.org/webworld/ramp/html/r8904e/r8904e05.htm#10.%20Staffinghttp://www.unesco.org/webworld/ramp/html/r8904e/r8904e05.htm#11.%20Equipment%20and%20materialshttp://www.unesco.org/webworld/ramp/html/r8904e/r8904e05.htm#11.%20Equipment%20and%20materialshttp://www.unesco.org/webworld/ramp/html/r8904e/r8904e06.htm#12.%20Planning%20and%20co-ordinationhttp://www.unesco.org/webworld/ramp/html/r8904e/r8904e06.htm#12.%20Planning%20and%20co-ordinationhttp://www.unesco.org/webworld/ramp/html/r8904e/r8904e06.htm#12.%20Planning%20and%20co-ordinationhttp://www.unesco.org/webworld/ramp/html/r8904e/r8904e05.htm#11.%20Equipment%20and%20materialshttp://www.unesco.org/webworld/ramp/html/r8904e/r8904e05.htm#10.%20Staffinghttp://www.unesco.org/webworld/ramp/html/r8904e/r8904e05.htm#9.%20Workshop%20accommodation%20and%20serviceshttp://www.unesco.org/webworld/ramp/html/r8904e/r8904e05.htm#8.%20Establishing%20a%20preservation%20and%20conservation%20programme


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conservation problems which are not already recorded or which have become

worse since the last survey.

8.2 Matching Treatment to Needs

8.2.1 Needs of the building. These may range from removal from a completely

unsuitable building to one which provides better conditions, through improvementsto the environment in which the records are stored (e.g. by the introduction of

portable humidifiers/dehumidifiers) and treatment of specific problems (e.g. bypest control or disinfection), to cleaning and the introduction of good housekeepingroutines.

8.2.2 Needs of the holdings. Here a range of treatment options exist:

a) full traditional conservation treatment;

b) minor repairs;

c) mass treatment;

d) substitution;

e) enclosing or re-enclosing in acid-free boxes, folders, etc;

f) denying access to documents pending future action;

g) doing nothing.

8.2.3 Choosing an option. In choosing an option the archivist should beguided by three considerations:

a) the value of the series or item, having regard both to its intrinsic value tie anymonetary value or special 'heritage' value) and to its informational value (i.e. the

quantity and quality of the unique information which it records) (in the USA

'intrinsic value' is used to embrace both these kinds of value - see 77);

b) the level of use to which a series or item is subjected or may in future be

subjected (this will to some extent be related to its informational value, but the two

are not necessarily identical);

c) the cost of implementing the various options.

When the archivist has assessed relative value and use, he can select the

appropriate option by reference to Table One. As will be seen, the choice of one

main option does not preclude the choice of a secondary option (e.g. a documentwhich has been given full traditional restoration treatment might then be


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microfilmed and the microfilm used for consultation to prevent recurrence of the

damage which occasioned the repair).

8.3 Establishment of Priorities

8.3.1 The building. In general the treatment of problems which affect the whole of

a building or a specific area of it should be given priority since this will be to thebenefit of all, or a substantial part of, the holdings. Immediate priority should

always be given to any problem which will spread or get worse if not treatedpromptly (e.g. leaking roofs, leaking water pipes, infestation by fungi, insects oranimal pests).

8.3.2 The holdings. A systematic programme of conservation treatment should be

established. Treatment of entire series rather than piecemeal treatment of

individual items should be the aim, although exceptions may have to be made forindividual items which have a high intrinsic value or which are in high demand for

use. In assessing priorities to establish such a programme account should be takenof value and use (or potential use) and also of the urgency of the need for

conservation treatment. Value and use should be assessed by an archivist, and the

urgency of the need for treatment by a conservator. A simple means of establishinga scale of priorities is for the archivist to give marks out of five for value and out of

five for use and for the conservator to give marks out of ten for urgency oftreatment. The sum of the marks should then be used in association with Table One

to indicate priorities for each of the appropriate treatment options.

Table one: Treatment options

VALUE

High Medium Low

USE OR

POTENTIAL

USE

High Restoration and

substitute for

reference

Minor repairs and

substitute for reference or

encapsulate

Substitute for

reference or

laminate

Medium Restoration Minor repairs or

encapsulate

Passive

conservation

Low Minor repairs Passive conservation Do nothing

dispose

9. Workshop accommodation and services

9.1 Construction. Whether the accommodation provided for the conservation

workshop is new construction or an adaptation of existing premises, a number of

factors have to be taken into account in determining its suitability.


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9.1.1 Floor loading. This should be adequate for the weight of the equipment to be

installed. Special care should be taken to ensure that the floor loading is adequate

for heavy items of equipment and machinery such as presses, guillotines andfumigation chambers.

9.1.2 Light. Natural light is essential but direct sunlight should be avoided. Hence,a north facing aspect in the northern hemisphere and a south facing aspect in the

southern are ideal. Where such an orientation is not feasible or in tropical areas

where neither aspect is ideal at all times of the year, external or internal blinds

should be provided. In addition good but glare-free and ultra-violet filteredartificial lighting (filters will need renewing from time to time) should be provided.

9.1.3 Height. Adequate clearance should be provided between equipment and theceiling.

9.1.4 Environment. The workshop should be provided with the same

environmental conditions as those of the storage areas, which should approach asclose as possible to the standards set out in 4.1.1 above. This is necessary to ensure

that any treatment undertaken is not undermined by changes in the environment

when the document is returned to storage. In addition an equable workingenvironment will be provided for staff. In tropical countries this will require the

installation of an effective ventilation system, dehumidifiers or, ideally, air-conditioning. In calculating the specification for this air-conditioning account

should be taken not only of the cubic capacity of the area and of the number of

staff working there, but also of the heat output of the equipment. This latter may beascertained from the manufacturers' specifications. A construction and layout

without internal walls will permit the maximum circulation of air. Separate wall-

mounted air-conditioning units are generally to be preferred to a central air-conditioning system on grounds of initial cost and ease of maintenance. Thespecial requirements of storage areas are dealt with in 9.7 below.

9.2 Size. It is not possible to lay down an ideal size for the accommodation for a

conservation workshop. The size of the accommodation to be provided will dependupon the number of staff to be employed, the range of processes and equipment,

and the scale of operations. It is prudent to provide for later expansion wherepossible (see 9.3 below).

9.2.1 Minimum standards. It is, however, possible to lay down some minimumstandards for the space required (16):

Conservators' workbenches 15 m each

Map and large document table 20 m to 25 m depending upon table size

Other items of equipment or processing areas 15 m each minimum

Document strongroom 10 m minimum


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Materials store 20 m minimum

Area for handling chemicals 15 m minimum

Office 20 m minimum

9.2.2 Circulation space. When the space requirements for the individualcomponents have been totalled, a further 25 per cent should be added for

circulation space. In a self-contained unit provision will also have to be made forwashing and toilet facilities and for first-aid and rest rooms.

9.3 Modular construction. Where it is intended that a conservation workshop

should be developed over a period of time, it may be cost-effective to provide ateach stage of development only such accommodation as is necessary at that stage.

This objective may be achieved by modular planning, which involves the drawing

up of an outline plan for the fully developed workshop and within that planproviding at each stage of development accommodation which meets immediate

needs and at the same time forms a component of the overall plan.

9.4 Lay-out. There is no ideal lay-out for a conservation workshop. How theequipment will be positioned will depend upon the range of processes and the scaleof operations. A specimen lay-out is provided at Appendix C for guidance. In

adapting this to specific situations a number of general principles should beobserved.

9.4.1 Work-flow. So far as possible a conservator should be able to carry out anentire process at or near to his workbench. However, where a range of equipmentand processes are involved these should be set out so as to facilitate the progress ofwork between the various items of equipment and processes. This is especially

necessary in respect of the several stages of binding and rebinding. In relating

work-flow to lay-out the objectives should be:

a) to plan space and operations to minimise the movement of the records and to

facilitate handling of records of varying sizes;

b) to make the flow lines as short as possible;

c) to keep flow lines in a horizontal plane;

d) to avoid cross-over of flow lines;

e) to integrate the work-flows of separate processes in such a way that those

relating to a common component run in parallel and others do not cross-over;

f) to give priority in proportion to the projected scale of operations where the flow

lines of the several processes cannot all be of optimum length.


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9.4.2 Ergonomic considerations. The positioning of individual items of equipment

should be such that the comfort, convenience and safety of the conservators is

maximised. To some extent the application of work-flow studies, by reducinglateral movement, will contribute to this. Other considerations involved are:

a) provision of good quality adjustable swivel stools and chairs with supportingbackrests for operations which can be carried out in a seated position;

b) positioning of switches, taps, etc. within easy reach of normal workingpositions;

c) placing of equipment which is not self-standing on benches or tables which areat a convenient height for the mode of working (standing or seated);

d) positioning hazardous machinery well away from the normal working area (e.g.fumigation chambers, if used, should not be placed within the conservationworkshop).

9.5. Relationship to other archival units. It is generally more efficient for anarchival conservation workshop to be contained within the main archive building

or complex of buildings. Its location within the archives will vary, depending upon

whether its accommodation is part of a planned new archive building incorporating

all component services, a conversion of accommodation within an existingbuilding or an additional building within an existing archive complex. However,

whatever the situation, its location should, so far as possible, be planned withregard to the relationship between the conservation workshop and other archivalservices. If it is not at ground floor level, a large goods lift will be required for themovement of equipment and materials.

9.5.1 Location. The optimum location of a conservation workshop may be

established by the same principles of work-flow as those applied to determine thelay-out within the workshop itself (16). The other units with which there will bethe closest relationship are likely to be:

a) storage areas: for the ease of retrieval and replacement of documents whichrequire conservation treatment;

b) reading rooms: for ease of transfer to the workshop for first-aid repair ofdocuments found in use to be damaged or decayed;

c) reprographic department: for convenience in preparing damaged or fragile

documents for copying or for preservation microfilming;

d) loading bay: for the receipt of equipment and materials.


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e) lifts, 'paternosters' or stairs: for the transport of documents, equipment and

materials within the building.

9.6 Services. The main services required by a conservation workshop are

electricity and water. Guaranteed standards of supply are desirable and where theseare not met by the normal public service, special arrangements should be made.

9.6.1 Electricity. Adequate power outlets should be provided for all electrical

equipment planned, with several spare outlets to provide flexibility. Considerationshould be given to floor or ceiling mounted outlets so as to avoid long runs ofcabling to workbenches and equipment, which constitute a safety hazard. Where

the local electricity supply is erratic, it may be desirable to install a generator

which can substitute for the local supply when necessary. It is essential to specifythe standard local voltage when ordering from manufacturers or suppliers

equipment which is dependent upon electricity. Equipment for the European andAmerican markets is manufactured to operate on different voltage standards andwhere equipment is manufactured to meet only one of these standards, it may need

to be specially adapted for use with the local voltage. Some equipment tea powerguillotines) may require a 3-phase supply.

9.6.2 Water. An adequate supply of water is essential for many conservation

treatments. Where the quality of the water supply cannot be guaranteed, or doesnot meet the required standards, filters should be installed to remove harmful

impurities and to maintain the required level of softness/hardness. For some

processes distilled or deionized water will be required.

9.6.3 Drainage. Large quantities of liquid waste will have to be disposed of. Thiswill have to be done in accordance with accepted safety and environmentalstandards. Where the public drainage facilities are not adequate, separate

arrangements will have to be made.

9.6.4 Chemical waste. Chemical waste in both liquid and gaseous forms will haveto be disposed of. This also will have to be done in accordance with accepted

safety and environmental standards.

9.7 Storage.

9.7.1 Document strongroom. A strongroom in which documents will be kept whileawaiting or undergoing conservation treatment should be provided. This should be

constructed to the same standards as the main storage areas in the archive, for

example:

a) floor loading: at least 2,000 Kg/m ;


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b) minimum fire resistance: floors and ceiling - 2 hours; doors - self-closing, no

distortion for one hour; no windows;

c) ceilings to be impervious to water;

d) fire detection and alarm system to be installed; fire extinguishers, hoses or

sprinklers to be sited within the strongroom;

e) environment: temperature - 15-22 C; relative humidity between 35% and 65%,preferably below 55%; neither temperature nor relative humidity should cycle by

more than 1% C and 5% respectively (see 4.1.1);

f) internal wiring: mineral insulated copper sheathed cable with screwed joints;

g) lighting: fluorescent tubes with diffusers and ultra-violet light filters; externallight switches;

h) shelving: non-combustible materials with non-corrodible, non-toxic, non-acidicfinish; should permit free circulation of air; bottom shelves to be set at 15 cm

above floor level; top shelves to be so that at least 15 cm remains between the topof the documents and the ceiling;

i) security lock (but openable from within).

9.7.2 Materials store. The store for materials should be sufficiently large to hold atleast two-years normal stocks. It should be fitted with shelves and lockablecupboards as required. The environment should be controlled to maintain an

equable temperature and relative humidity to prevent deterioration of perishable

stocks (e.g. paste, laminating tissue). A fire detection and alarm system should beinstalled, together with hand-held fire extinguishers.

9.7.3 Chemical store. Ideally this should be away from the main building. A sinkand bench with chemical resistant surfaces and a fume hood should be provided for

chemical handling and use. A refrigerator should be provided for chemicals which

require low temperature storage. The store should be well ventilated, with anextractor fan for venting to the roof any fumes caused by accidental chemical

spillage. A fire detection and alarm system should be installed together with hand-held fire extinguishers suitable for fighting chemical fires. First-aid equipment and

protective clothing should be provided.

10. Staffing

10.1 Functions. See Appendix A for job descriptions.

10.1.1 Archival functions. Conservation should be at the forefront of everyarchivist's priorities. In addition to specific responsibilities for advising on the


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value and use of material which has been identified as in need of conservation

treatment so as to determine priorities, archivists should be seeking in their every-

day activities to ensure that documents are handled carefully by staff and publicand that they are not damaged, whether deliberately or accidentally.

10.1.2 Conservation functions. The work of deciding on appropriate conservationtreatment is the joint responsibility of the archivist and the conservator; carrying

out that treatment is the responsibility of the conservator. This requires a wide

range of specialist knowledge of the nature of documents and the best treatment in

specific circumstances, as well as the necessary dexterity and expertise to carry outthat treatment. This means that conservators should be more than just skilledcraftsmen; they should be as professional as archivists, with whom they should

work as equal and respected members of the preservation team.

10.1.3 Sub-professional functions. Some treatments (e.g. lamination,encapsulation, deacidification) require only limited expertise and may be entrustedsafely to trained technicians working under the direction of conservators. Other

tasks, especially passive conservation activities, such as boxing and reboxing,cleaning the storage areas, etc. will not require any specific expertise provided that

they are performed conscientiously under proper management.

10.2 Management.

10.2.1 Preservation management. Preservation, as defined in 2.1.1 above, is the

responsibility of the top management of every archival institution. In terms of day-to-day management this responsibility will be delegated to the Preservation

Manager, who should be a member of staff of equal status to the heads of otherdepartments within the institution. He (or she) should be responsible for preparingfor approval and carrying out a preservation and conservation programme which

includes the physical care of the records and the identification and treatment of any

conservation needs, including making arrangements for the provision of substituteswhere appropriate. Initially management at this level will almost certainly have to

be undertaken by an archivist, who should have a sufficient grasp of the technicalprocesses to discuss them constructively with conservators but need not be a

conservator himself. In the longer term there is no reason why a suitablyexperienced conservator should not be considered for this post. Financialresponsibility will normally be located at this level. There are advantages in

combining the post with that of general responsibility for other technical areas (e.g.reprographics).

10.2.2 Conservation management. A Senior Conservator should have day-to-day

control of operations and should decide immediate priorities in the light of general

guidelines agreed with the Preservation Manager, to whom he (or she) should be

responsible for: