jaic 2005 - preventive conservation and the exhibition process

7/25/2019 Jaic 2005 - Preventive Conservation and the Exhibition Process

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JAIC 2005, Volume 44, Number 3, Article 8 (pp. 245 to 257)

PREVENTIVE CONSERVATION AND THE EXHIBITION PROCESS:

DEVELOPMENT OF EXHIBIT GUIDELINES AND STANDARDS FOR

CONSERVATION

TOBY J. RAPHAEL

ABSTRACTYears of producing exhibits had shown that only by involving conservation

early and systematically throughout the exhibit process can a museum ensure preservation-friendly exhibitions. To address this need the National Park Service embarked on the

development of a set of guidelines and standards to ensure the incorporation of conservation

into exhibit planning, design, and production. This paper describes the objectives and results

of the publication of the guidelines, the first phase of this project.

TITRELa conservation prventive et les procdures d'expositions: Dveloppement de

directives d'exposition et de standards de conservation. RSUMDes annes d'exprience

ont dmontr que le seul moyen d'assurer des expositions en harmonie avec les principes de

conservation consiste impliquer de faon systmatique les restaurateurs au dbut et tout au

cours du processus d'exposition. Afin d'adresser ce besoin, leNational Park Service(service

des parcs nationaux) s'est engag dans le dveloppement d'un ensemble de directives et de

standards qui garantissent l'incorporation des principes de conservation dans la planification,

le design et la production des expositions. Cet article dcrit les objectifs et les rsultats de la

publication de ces directives, qui n'est en fait que la premire partie de ce projet.

TITULOLa conservacin preventiva y el proceso de exhibicin: el desarrollo de pautas y

estndares de conservacin para exhibiciones RESUMENAos de experiencia

produciendo exhibiciones haba mostrado que nicamente al involucrar la conservacin

temprano y sistemticamente en el proceso de crear una exhibicin haca posible que un

museo produjera exhibiciones que favorecieran la preservacin de los objetos. Para llenar

esta necesidad elNational Park Service(Servicio Nacional de Parques) comenz a


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desarrollar unas pautas y estndares que aseguren que la conservacin sea incorporada en el

proceso desde la planificacin, el diseo y la produccin de una exhibicin. Este articulo

describe los objetivos y los resultados de la publicacin de las pautas, que es la primera fase

de este proyecto.

TTULOConservao preventiva e o processo de montagem de exposio:

Desenvolvimento de diretrizes para exposio e normas de conservao. RESUMOAnos

de experincia produzindo exposies mostraram que, somente quando as atividades de

conservao so incorporadas ao processo de montagem de exposies desde o incio, e de

forma sistemtica, o museu consegue assegurar exposies que levem em considerao a

preservao. A fim de abordar essa necessidade, oNational Park Service(Servio Nacional

de Parques) comeou a desenvolver um conjunto de diretrizes e normas, capazes de

assegurar a incorporao da conservao ao planejamento, desenho e produo de

exposies. Este artigo descreve os objetivos e os resultados da publicao das diretrizes,

primeira fase deste projeto.

The exhibition is, in fact, a compromise between the reason that you acquire and save each

object and those conditions that will preserve your objects for the longest period of time.

Carolyn Rose

La exhibicin es, en realidad, el termino medio entre la razn por la cual se adquiere y

guarda cada objeto y aquellas condiciones que preservarn los objetos por el mayor tiempo

posible.

Carolyn L. Rose


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1 INTRODUCTION

Throughout the 1980s and '90s, conservation requirements for exhibitions were confusing

and elusive for the exhibit specialists, the many skilled individuals who focus on planning,

designing, and fabricating museum exhibitions;this may include exhibit planners,

developers, curators, designers, producers, and installers. No single resource for

conservation guidance on exhibitions could be found, no source where alternative

techniques or applications could be studied. Lack of awareness and understanding of this

body of knowledge took a tremendous toll on the preservation of museum collections.

Exhibit specialists were unable to find even simple answers to their conservation concerns,

from appropriate exhibit rotation schedules for vulnerable objects to the requirements forsilica gel humidity stabilization.

Because of the dearth of information on how to integrate preventive conservation in

museum practices, the author began writing technical notes on exhibit preservation subjects.

These notes were included in a comprehensive set of guidelines entitled Exhibit

Conservation Guidelines: Incorporating Conservation into Exhibit Planning, Design and

Fabrication, which was published by theNational Park Service (NPS) in 1999. The

publication was written with the support and assistance of Conservators Martin Burke and

Nancy Davis, and Exhibit Designer Kevin Brooks. Carolyn Rose, one of the founders of

preventive conservation, painstakingly edited the manuscript and was adamant that her two

principal concerns be emphasized, that conservators must become involved early in the

exhibit process, and must be effective team players working cooperatively with exhibit

planners and designers. Rose utilized the completed Guidelines extensively in her teaching

both in this country and abroad.

This article will summarize the motivation for and development of both theExhibit

Conservation Guidelinesand theMuseum Conservation Standards for the Development of

Object-based Exhibitions, which is currently being written. Due to its diverse goals and

audiences, Guidelines includes several different formats: a narrative section provides the

framework for introducing each individual guideline and its discussion points; technical

notes supplement the guidelines with examples; and technical drawings illustrate
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conservation details regarding exhibit case design. The Standards are being developed to

address the need for more prescriptive requirements that will incorporate conservation

concerns into exhibition design.

2 CONFLICTING RESPONSIBILITIES

Museum exhibition is where a collision can occur between conflicting responsibilities to not

only preserve collections but to use them as well. Over the past century the mandates for

preservation and use have been regarded as inherently incompatible. In other words,

exhibition and the use of objects are at the opposite end of the spectrum from collections

preservation. It is our goal to create another dynamic where use of collections does not

necessarily conflict with their preservation in perpetuity. In recent years, progressive andinnovative approaches have resulted in considerable advances, and exhibit conservation has

taken root and is developing into a distinct specialty.

The goal of exhibit conservation is to design and produce preservation-friendly exhibits that

attract and inform the public. After decades of exhibit experience we are convinced that the

safe display of cultural material does not need to compromise sound design or informative

interpretation. The perceived conflict of the past, the tension between preservation and use,

can be alleviated or at least greatly diminished.

The overall challenge is to produce exhibitions that systematically integrate preservation

criteria into the exhibit planning, design, and fabrication processes. A successful museum

exhibit can fulfill its educational intent, be aesthetically engaging, and conscientiously

protect the objects on display.

3 THE COMMON RISKS OF EXHIBITION

Behind the effort to regulate the exhibit development process is the fact that museums,

naturally, put their most significant objects on display and, by doing so, place these

collections at much greater risk than if they had remained under the controlled conditions of

protective storage. It is these risks that must be addressed in a systematic manner, and

exhibit specialists, until recently have had little help in discovering what are the givens


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and what are the options in terms of conservation.

The NPS, like the Smithsonian Institution, is responsible for caring for this country's

national collections. NPS collections, approximately 100 million items, are generally located

at or near their original historic locations. As a result, they are almost always exhibited in

buildings not originally designed as museums and which do not meet museum standards.

Understandably, the concept of the exhibit micro-environment has come to play a central

role in preserving any cultural resources put on display in these challenging environments.

A well-designed and well-engineered exhibit case can provide a highly effective micro-

environment. When designed and fabricated under the oversight of knowledgeable

conservators, the exhibit case becomes the most important and cost-effective tool forpreserving vulnerable collections. The NPS has begun to refer to these enclosures as

conservation-grade exhibit cases. From the perspective of sustainability, the micro-

environmental approach to exhibiting vulnerable collections makes perfect sense. Energy

consumption is reduced. The need to install costly, building-wide air controlling systems to

meet museum standards is alleviated. Accordingly, the exhibit case is considered central to

preservation technology and is a major focus of discussion and specifications.

Although display in cases and vitrines has been the norm for most museum exhibits, the

pitfalls and benefits of conventional display enclosures are only now being calculated by

conservation specialists and shared with exhibit specialists. The assumption has been that

the traditional display case is an effective means of mitigating damage while objects remain

on exhibit. The truth is that, until now, exhibit specialists have had little information about

the impact of common exhibit cabinetry on vulnerable collections or the degree to which

they actually provide protection. As more is learned about the traditional exhibit cabinet

from scientists, there is serious reason to be concerned. Research indicates that the exhibit

case has an alarming potential for exacerbating the deterioration of its contents.

The strategy to promote is that a properly engineered enclosure has an equally great

potential for protecting and preserving vulnerable collections. When objects on display are

housed in well-designed and carefully fabricated cases, they can be effectively preserved at

levels remarkably close to those provided in storage. The one risk or mechanism of change


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that is by definition different from storage conditions is exposure to light. Recent

developments in technology, however, are giving us new ways to circumvent this agent of

deterioration: witness the huge variety of commercially available visitor-driven occupancy

sensors and white light LED lighting systems that do not produce ultraviolet or infraredradiation. The technology is now available for museum staff to require that their display

enclosures methodically preserve their collections in conservation-grade cabinetry. When

procuring new casework, NPS museums will soon have access to new tools to specify what

preservation features and levels of performance are to be expected.

4 BARRIERS TO CONSERVATION-FRIENDLY EXHIBITIONS

The exhibit development process followed by the NPS, and that of most cultural institutions,has not fostered collaboration among the museum exhibit specialists and conservators. Too

often the process has engendered isolation of the team players and poor communication

among these specialists. For a number of complex reasons the process, or lack of process,

seems to fall short of producing the well-balanced solutions that are needed for a fully

successful exhibition. For instance, in reality:

Different exhibit specialists rarely utilize a standardized process for developing

exhibits.

There are few routine procedures for incorporating conservation concerns.

Rarely do exhibit designs take full advantage of both the most current design

possibilities and state-of the-art preservation features.

Rarely are summative evaluations included to establish whether an exhibition is

successful from a preservation standpoint.

One reason museum exhibitions do not consistently achieve the highest level of preservationis because of deficiencies in general staff preparation and training. There is a lack of cross-

training between exhibit specialists and conservators, and it is fair to say that neither of these

museum specialists is prepared to interact successfully. Just as there is too little focus on the

exhibit process within conservation training programs, conservation training for exhibit

specialists is mostly non-existent.

Within conservation training programs, exhibit developers, planners, and designers


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are rarely seen and familiarity with the exhibit development process is, for the most

part, not emphasized.

Because formal training programs are rare, museum exhibit planners and designers

often have little familiarity with conservation, and specialists in commercial firmshave even less opportunity to actually work with a conservator.

Museum personnel, in general, are not taught the importance of balancing

preservation and use criteria for exhibitions, and most have not had access to written

guidance on how to facilitate conservation-friendly exhibitions.

The lack of a methodical development process for exhibits and a deficient understanding of

how to incorporate conservation concerns frequently creates an impasse resulting in

frustration and unwillingness to compromise. Project after project has shown that where

poor communication persists, low expectations and unhelpful assumptions come into play.

Many exhibit specialists hold the belief that conservators are uncompromising and are not

friends of the exhibition but merely advocates for the collections. Preservation requirements

and exhibit conservation features can be complex and often appear elusive to exhibit

specialists. Collection and conservation staffs often lack the experience and technical

understanding needed to communicate their needs in ways that designers and fabricators can

understand. Conservators are rarely comfortable reading blueprint drawings and using thedesign/fabrication language of specifications.

These communication limitations have served to limit access to the body of conservation

knowledge, which has, in turn, had a serious and negative impact on the exhibit process and

ultimately the collections. To begin to address this problem, the author began to develop

conservation guidelines designed to improve the working relationship between conservators

and exhibit specialists.

5 POLLING OF COLLEAGUES

Before initiating the project to develop conservation guidelines and a plan for developing

standards, dozens of colleagues involved in producing museum exhibitions and supplying

conservation advice were informally surveyed. The findings of the survey revealed seriously

conflicting viewpoints.


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Nearly all of the conservation specialists interviewed expressed a belief that the exhibit

processes that they were involved in did not adequately or systematically incorporate the

preservation needs of the collections going onto display. Preservation specialists felt that

they had the long-term picture in view, while the exhibit specialists focused on short-termuse of collections. When polled, conservators indicated encountering several problems

working with exhibit planners and designers, such as:

undervaluing the well-being of exhibited objects

continual design changes requiring the reinvention of conservation solutions

not learning from the previous exhibit conservation experiences

not including conservation specifications on drawings

resistance to producing mock-ups and prototypes

The poll indicated that many exhibit designers believed that conservation advice was given

without regard for the project budget, and if accepted, often would compromise exhibit

design and the exhibition's effectiveness. More specifically, when polled, exhibit planners

and designers readily pointed to several problems with the conservation recommendations

they were given:

inconsistent information and variation from conservator to conservator

information offered at inopportune times

limited communication skills and familiarity with design language

vague recommendations and unrealistic performance expectations

solutions and recommendations were too often untested

limited regard for financial consequences of recommendations

Obviously divergent viewpoints were not helping the exhibit process. Everyone surveyedknew the situation needed to be addressed.

6 DEVELOPING THE GUIDELINES AND STANDARDS

To address this need a two-phase preventive conservation project was embarked upon: first,

to create a preservation framework, Guidelines, and second, to provide a more prescriptive

tool, Standards, to ensure that conservation be incorporated effectively in NPS exhibits.


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Another underlying goal was to develop a sense of shared responsibility for collection

conservation, as preservation-friendly exhibits require a close, constructive working

relationship between exhibit and conservation specialists.

The overall goal of phase one was to provide the specialists with the preservation

information they need. Completed and published byNPS in 1999,Guidelinesis summarized

in the Appendix. This publication aims to:

organize and give access to existing technical information

facilitate access to recent developments in the field

improve interdisciplinary communication

share accumulated exhibit experience and lessons learned

unify and consolidate preservation recommendations

connect preservation theory to actual applications and products relevant to exhibits

The second phase of the project, the publication of Standards, is needed because

the Guidelinesdo not include prescriptive or mandatory requirements. The standards are to

play a different role, ensuring that:

conservation concerns are addressed early in the process exhibits include conservators in the critical aspects of the exhibit timeline

baseline considerations widely known in the field are incorporated

responsibility for preservation is widely shared

conservation criteria are established and are influential in exhibit design

recommended practices and the alternative options are known

appropriate levels of conservation response are considered

buildable and maintainable designs are generated actual performance is acceptable

solutions are found within budget and timetable

Standards and specifications exist for nearly every product and material found in NPS

museums, but ironically, not for use of the museum exhibition collections on display. A set

of properly developed standards, basic requirements and specifications to ensure responsible

preservation practices, could give museum specialists a much-needed tool for:1)
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understanding preservation features and levels of performance that can be expected of

museum exhibits; and, 2) providing criteria to judge compliance and acceptability. Such a

document is increasingly being considered indispensable for our institution to meet its

preservation mandate, and could serve other cultural institutions as well, by providing animportant tool for creating preservation-responsible exhibits.

The drawbacks of using standards were appreciated. Standards can outlive their usefulness,

restrict creativity, be difficult to enforce and difficult to measure. Conservation standards

were needed that would allow for a degree of flexibility; therefore, the standards being

written strive to affect the process by which exhibitions are created, not to standardize the

end product.

Standardsis being developed to address two aspects of museum exhibitions:

Section 1. Conservation standards for developing museum exhibits

Section 2. Conservation specifications for designing and constructing museum

exhibit cases

Exhibit specialists have a national organization and it is the National Association for

Museum Exhibitions (NAME) of the American Association of Museums. This organizationhas endorsed the NPS Conservation Standards project and anticipates that there will be

many opportunities to benefit from the NPS research and findings through future

publications, workshops and shared training programs.

7 ENSURING CONSERVATION A PLACE IN THE EXHIBIT PROCESS

Having the Guidelinesin place has assisted the NPS to integrate conservation practices into

its museum exhibition process. Diagrams and lists of conservation activities were included

to ensure understanding and to clarify the process. In particular, projects have benefited that

utilize exhibit contractors, on whom the NPS increasingly relies. The NPS, like many large

museums, depends on exhibit firms to develop and produce new exhibits and these firms are

provided a copy of the Guidelines. Each firm is also offered introductory training on the use

of the document and a discussion with an NPS exhibit conservator. Since publication five

years ago, the Guidelineshave been used outside the Park Service in dozens of museums


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nationally and internationally, and have been translated into Spanish and Vietnamese.

The creation of exhibit standards is now possible partly because of advancements within the

exhibits industry and conservation field, and because of the familiarity exhibit firms now

have with the Guidelines. Display technology and construction materials are now available

which allow exhibit specialists to better balance the need to present and interpret museum

collections with the conservation features necessary to protect them from needless loss.

After several decades of work with exhibit specialists and conservators, it has become

apparent that a conservation standards document is critical to our shared goal of ensuring

collection safety in museum exhibitions. Written standards will facilitate the inclusion of

conservation by everyone involved; conservation features can be more easily specified andincluded as routine exhibit components. These standards can be included in contracts from

the beginning, thus becoming an integral part of the procurement process. Other expected

benefits include:

The quality of exhibits will be more uniform. Discrepancies between diverse firms

with strong backgrounds in conservation and those with little experience will be

minimized and collections will not suffer as a result of these differences.

Debate will be curtailed. Unnecessary discussion will be shortened or eliminated,

such as, When does an exhibit merit an exhibit conservator being assigned? or

When must an exhibit case be used to display vulnerable objects?

Less time and resources will be spent reinventing conservation solutions. During the

planning and design phases a tremendous amount of time is spent re-establishing

basic preservation requirements and re-exploring well-known approaches.

More responsive design will result. Exhibit objects face diverse levels of risk in

different exhibits; however, the categories of risks stay the same. Standards will

allow conservation dialog to focus on the specific design development that will

withstand the levels of risks presented.

8 CONCLUSION

Because of a lack of easily available, well organized information, exhibit specialists who

plan, design, and produce museum exhibitions have had difficulty knowing how to


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incorporate preservation features into their work. Accordingly, the lack of awareness and

understanding of this body of knowledge has taken a serious toll on the preservation of

displayed collections. Preventive conservation techniques and technology are highly

relevant to this group of professionals; however, communication is infrequent betweenconservation and exhibit specialists.

As an exhibition conservator with the NPS at Harpers Ferry Center, the author was given the

opportunity to lead an effort to develop a comprehensive set of guidelines and standards

directed at improving the conservation of collections going onto exhibit. The Exhibit

Conservation Guidelinespublished five years ago has had a very positive impact towards

achieving well-balanced exhibitions. The next step, currently under development, is the

formulation and publication of conservation standards for the production of fully successful,

preservation-friendly exhibitions.

APPENDIX

APPENDIX: A SUMMARY OF STRATEGIES AND PRACTICES FOR

PRESERVATION-FRIENDLY EXHIBITIONS


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(FromExhibit Conservation Guidelineswith permission of the author)

1 A. INTEGRATED PLANNING

1.1 Conservation and the Exhibit Process

1.1.1 Integrating Conservation into the Exhibit Process

Integrate conservation early in the exhibit planning phase. Make a commitment to

preserving objects placed on exhibit by including conservation concerns throughout

the development and production of the exhibit.

Provide adequate time and resources. Build in enough time for development and

review of technical designs, case prototypes, lighting mockups, and the testing of

proposed materials. The schedule must allow for safe handling, exhibit mount

making, and installation of objects. Include the costs of addressing preservation

issues, such as treatment and special casework, in the budget.

1.1.2 The Exhibit Team

Work cooperatively. Each team member should take responsibility for understanding

basic conservation issues and working with other members to achieve preservation-

responsible displays. The search for balanced and appropriate solutions often

requires compromise.

Hire supportive design staff. Use designers who are experienced in working with

exhibit conservators and firms that have a history of producing preservation-

responsible exhibits.

Demand high construction standards. Develop drawings and specifications that

clearly articulate the intended conservation features; consider including performance

criteria. Oversee production contractors to ensure that conservation components are

built as specified.

1.1.3 The Role of the Exhibit Conservator

Include an exhibit conservator on the exhibit team. Select a conservator who is

qualified in the specialty of exhibit conservation. Often, a part-time consultant is


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sufficient.

Involve the exhibit conservator in the earliest stages and throughout the exhibit

planning, design, fabrication, and installation process. An exhibit conservator should

set conservation criteria, attend planning meetings, review conservation-relateddecisions and designs, and assess prototypes and exhibit work after installation.

1.2 Preservation-Responsible Planning

1.2.1 Selecting Objects

Select appropriate display objects. Make the selection in conjunction with a

conservator who can establish the current condition of the object and the preparation

and care required before and during the exhibit.

Avoid selecting too many objects. Review the number of objects that can be

accommodated safely within the available space.

Consider the aesthetics of each object. Object selection should include curatorial

review of the visual message presented. Incomplete, deteriorated, or dirty objects

may require extensive treatment.

Avoid permanent exhibit of objects. Consider rotating vulnerable objects,

substituting alternate objects, or using reproductions. When possible, use a

reproduction to demonstrate the function of an object.

Allow enough time and resources to safely prepare, mount, install, or replicate

exhibit objects.

1.2.2 Establishing Conservation Criteria

Review the objects. Examine each object chosen for display to determine its current

condition and individualize its conservation requirements. Complete a written

condition assessment of the objects.

Establish necessary but realistic conservation criteria. Base the requirements on an

assessment of the individual objects, the likely environment in the exhibit space, and

current conservation research.


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Address the conservation criteria. Incorporate the conservation recommendations

into the exhibit design. The designer, conservator, curator, and other team members

must work cooperatively to ensure practical display methods that preserve the

objects.

1.2.3 Collections Management

Ensure safe handling. Provide training for anyone who handles an object during the

exhibit process. Dedicate a clean, secure space for temporary storage of objects

during exhibit development, construction, and installation.

Stabilize all objects. Have a conservator document their condition and provide a

treatment proposal for those that need care. Secure the necessary funding for treatingunstable objects before display.

Document objects. An exhibit object list should include the accession or catalogue

number of each object. Photographs of the objects and floor plans marked with

object location facilitate security and condition checks.

Protect objects during photography. Limit an object's total exposure to light, and

avoid overheating objects with studio lights. Use a flash system, especially for light-

sensitive objects. Always provide appropriate support for objects.

2 B. EXHIBIT DESIGN STRATEGIES

2.1 Appropriate Design Solutions

2.1.1 Multilevel Conservation Response

Choose an appropriate and efficient response from among the multiple options

available. Consider what level of protection is obtainable and what kinds of tradeoffs

each will impose on the conservation criteria.

Consider both macro and micro approaches. Weigh the benefits and costs of

addressing conservation criteria throughout the exhibition against creating micro


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solutions using exhibit cases.

2.1.2 Exhibit Format and Layout

Use enclosed display when possible. Avoid open display except in historic house

museums and some gallery settings or when an object's size makes enclosure

impractical. Open display should never be a routine exhibition option or one chosen

solely for financial reasons.

Allow sufficient room for traffic flow. Design the exhibit to avoid accidents. Provide

adequate space through the exhibit and around exhibit cases for the easy movement

of individuals, groups, and people in wheelchairs.

Group similar objects. Consolidating the location of collections with similar

conservation criteria will make it easier and cheaper to meet the design goals.

2.2 Understanding the Exhibit Environment

2.2.1 Temperature and Relative Humidity

Know the environment. Monitor an exhibit space for one year to obtain baseline

information about the temperature and relative humidity. Review theseenvironmental data for each exhibit to determine if existing conditions meet the

conservation criteria.

Control the environment within the entire exhibit space. In general, keep temperature

between 60 and 70F (15.5 and 21C) and relative humidity between 40 and 60%,

eliminating rapid cycling of temperature and relative humidity. (Requirements for

special objects and certain geographical areas may vary.)

Locate sensitive objects in the most stable locations. Do not place moisture-sensitive

collections in the path of direct sunlight, near heating or air-conducting ducts, against

external walls, or in damp locations such as basements. Avoid putting cases and

framed works along exterior walls.

Provide additional control for sensitive objects. Use sealed cases to slow air

exchange and thus stabilize environments inside cases. When called for, create a

microclimate by incorporating silica gel or other climate control products within


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cases that contain moisture-sensitive materials.

2.2.2 Particulate Contamination

Enclose sensitive objects. Use high-efficiency filters in HVAC equipment to remove

particles down to 10.3 microns (6080%). Change filters regularly.

Use localized filtration equipment. If improving filtration throughout the museum is

not feasible, consider using room-sized units in construction areas or within the

exhibit space.

2.2.3 Chemical Pollutants

Monitor pollutants. Assess the air quality within the museum to establish the ambient

level of contaminants. This knowledge will point to the measures necessary to meet

the conservation criteria for an exhibit.

Incorporate chemical filters in the environmental systems. For susceptible collections

or in highly polluted locations, include activated charcoal or potassium

permanganate filters in the environmental system.

Provide air circulation. Adequate air circulation will lower total concentrations; high

rates of airflow over or near objects, however, increases their exposure. Design theexhibit layout to minimize the objects' exposure to pollutants.

Select stable construction materials. Avoid materials known to outgas, become

acidic, or lose their physical or chemical stability with age.

Aerate the exhibition space before object installation. Allow time for initial levels of

outgassing from new materials to dissipate.

Enclose sensitive collections. Cases that incorporate a chemical pollutant scavenger

provide a high level of protection for sensitive objects.

2.2.4 Exhibit Lighting

Develop a lighting plan that responds to the established conservation criteria.

Produce the plan early in the process to allow enough time for coordination of the

complex issues that determine final lighting choices and levels.

Limit total light exposure. Provide separate lighting for security checks, exhibit


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cleaning and maintenance, object installation, and other routine work. Turn off lights

during nonpublic hours so as not to expose objects to light unnecessarily. When

possible, use occupancy sensors in the room or at the case to turn lighting on and off

during visitation hours.

Filter all sources of ultraviolet radiation. Use commercially available filters on all

light sources to reduce the levels of ultraviolet radiation to 10 microwatts per lumen.

Control infrared radiation. Locate objects at least 24 inches from fluorescent lights

and at least 36 inches from incandescent or tungsten halogen lights.

Exclude sunlight. Design new exhibit spaces that prevent daylight from reaching

display objects. Daylight that is already present in the exhibit space should be

filtered for UV radiation and lowered in intensity.

Construct lighting mockups to evaluate the amount and quality of light provided by

the proposed lighting plan. Measure final light levels and adjust them accordingly

during installation.

2.2.5 Biological Infestation

Examine objects for signs of infestation and active mold as part of the preliminary

condition check. If signs of infestation are found, consult a conservator abouttreatment options.

Design exhibits to inhibit infestations. Make sure the exhibit area is insect-proof by

screening open windows or doors, filling gaps in the building construction, and

avoiding gaps and undercuts where dust can collect.

Enclose objects. When the risk of infestation is high, place susceptible objects inside

well-sealed cases or sealed acrylic boxes to prevent new infestation. Limit the gaps

and holes to prevent insect entry.

Avoid introducing insects through props and unchecked exhibit materials. Do not use

wool carpets and other materials that attract and harbor insects. Avoid using organic

exhibit props. Fumigate vegetative props or expose them to freezing temperatures

before bringing them into the museum.

Control human behaviors that encourage infestation. During exhibit production and

installation and after the exhibit opens, never allow food in the object holding areas


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or the exhibit space, even if no objects are in the area.

2.2.6 Physical Security

Conduct a risk assessment. Identify the likelihood of theft and vandalism. Provide

protection against human damage. Exhibits in a museum with a history of vandalism

and theft may require additional security measures.

Provide the appropriate level of protection. Tailor security features to the

vulnerability of the objects. Highly vulnerable and valuable objects require more

sophisticated protection measures than others.

Use secure case hardware. Mount objects to panels or shelves, bolt freestanding

cases to the floor, and lock exhibit cases.

Facilitate authorized curatorial access to the objects. Each object in an exhibit should

be readily removable without having to remove or disturb adjacent objects.

2.2.7 Emergency Preparedness and Fire Protection

Develop fire protection and emergency response plans. The museum staff should

have an emergency plan for each exhibit space. The plans should minimize threats to

museum objects, protecting them during a disaster, during their evacuation, and aftera disaster.

Perform a risk assessment and address potential problems. Anticipate the types of

damage that may occur to display objects. For example, avoid placing objects,

especially if they are water-sensitive, in the path of fire sprinkler heads.

3 C. EXHIBIT CASE DESIGN

3.1 Conservation and Case Design

3.1.1 Designing a Conservation-Grade Case

Design cases as protective enclosures. Take advantage of a well-designed case to

control the microenvironment of sensitive collections. A case designed with the

participation of an exhibit conservator is an efficient and often cost-effective way to

meet conservation criteria for an object.


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Establish performance criteria. Determine what conservation features will be built

into each case, and clearly identify performance criteria for each feature. Design the

case to provide this performance.

When possible, build and test a prototype case to decide whether it meets designobjectives. Modify the case until acceptable performance is achieved.

Provide detailed, explicit drawings and specifications. Inspect cases during

fabrication to ensure that the fabricators stick to specifications and construction

tolerances.

Test the fully assembled case in its final location to ensure that conservation criteria

have been met. Such testing should occur before object installation to allow for

adjustments.

3.1.2 Case Stability, Security, and Access

Construct a physically stable, structurally secure case. Limit vibration by using

movement dampening devices. Include space for weight ballast to prevent jarring

and tipping.

Provide appropriate security features. Choose from security options to include the

level of protection that the design team considers prudent. The case strength,resistance, and security devices should match the projected threat from vandalism

and theft.

Provide for legitimate access. Incorporate doors or other practical access options in

the case design. Ensure that a single person can enter the case and remove artifacts

with ease and in a short amount of time.

3.1.3 Sealed Exhibit Cases

Use sealed display cases when appropriate. Determine which objects, if any, require

protective microenvironments, and design cases accordingly.

Design well-sealed cases with tight joints and with gaskets around all removable

panels and entry doors. Choose construction materials that limit air exchange and,

for climate-controlled case designs, are not moisture-permeable. Well-sealed cases

should allow no more than one complete air exchange every 72 hours.


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Use conservation-approved sealants. Minimize leaks with adequate gaskets and

caulk. Always choose materials that do not outgas.

Test case performance. When possible, use leak detection equipment to identify air

leaks and determine air exchange rates. Modify the case design or add caulk andgaskets to reduce leakage.

3.1.4 Ventilated Exhibit Cases

Use ventilated cases for appropriate applications. Select vented cases for use in an

exhibit space with a good climate-control and pollutant-control system that functions

24 hours a day.

Control the design and construction of ventilated cases. Design well-sealed cases,

and place an adequate number of vents to provide for air movement. Filter the vents

to prevent dust, insects, and chemical pollutants from being drawn into the case.

Use positive-pressure cases when appropriate. Museums with good climate-control

systems may be able to use these cases, which are easier and cheaper to build

because they do not have to be well-sealed.

3.1.5 Lighting Design within Cases

Isolate lights from the display chamber. Place all lighting fixtures outside the display

area of a case. Contain any lights that are integral to the case in a separate

compartment. Seal off the lighting chamber to prevent the entry of insects, heat, and

dust into the display chamber.

Reduce heat gain and temperature cycling. Ventilate the lighting chamber to

dissipate heat from fixtures and lamps. In larger cases or cases located in enclosed

spaces, electric fans may be required. Heat gain inside the display chamber should beno more than 2F when lights are turned on.

Incorporate heat-reflecting and insulating materials when necessary. Consider heat-

reflecting glass or double-glazed construction for panels that separate the lighting

chamber. To help prevent heat buildup, use metal products to construct the chamber

and insulate lighting compartments below the display area.

Develop an appropriate case lighting plan. Choose a lighting system that allows


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sufficient distance between lamps and separation panel. Control heat buildup in the

lighting chamber by using efficient, low-voltage systems, reducing lamp wattage,

and, when necessary, using fans.

3.2 Microclimates within Exhibit Cases

3.2.1 Humidity-Control Principles

Design a well-sealed case that will support humidity control. To achieve an effective

microenvironment, minimize the air exchange between the case and the room. No

more than 1 air exchange per 72 hours is recommended.

Provide adequate air circulation within the case. Use a perforated deck or a floating

deck with a perimeter gap to allow air to circulate throughout the display chamber

and the maintenance chamber.

Provide separate access for maintenance. Climate-control equipment and materials in

both active and passive systems will need to be maintained and adjusted.

Test the case before enclosing objects. Ensure that the humidity inside the case meets

the conservation criteria.

Monitor the interior relative humidity for the duration of the exhibit. If identical

cases are used, systematic sampling may be adequate.

3.2.2 Active and Passive Humidity Control

Establish whether the goal is stabilization or control. Stabilizing the humidity inside

a case is usually sufficient unless objects require a highly restrictive or specific RH

range.

Select an appropriate method. Use mechanical systems cautiously, and choose

specific equipment carefully. When using a passive system, design the case to

include a holding area for the moisture-absorbent medium with easy access for

maintenance.

Provide safeguards for mechanical systems. Locate equipment in a maintenance area

that does not transfer heat or vibration to the objects. Provide a constant power

supply (including emergency generators), a monitoring alarm to alert staff to

equipment malfunction, and adequate water supply and drain lines.


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Include appropriate and sufficient moisture-absorbent materials for passive control.

Systematically calculate the quantity and type of silica gel or cellulosic materials to

be used.

Test and monitor the case. Evaluate the initial performance of active or passivesystems before enclosing objects. Monitor the relative humidity for the duration of

the exhibit to alert staff when maintenance is required.

3.2.3 Pollution-Control Systems

Incorporate enough absorber to remove pollutants for six months to one year.

Objects must never touch a chemical absorber.

Ensure unrestricted airflow. Case design should encourage air movement across the

surface of the pollutant absorber. Ensure that the case is well-sealed.

Provide access to change the absorber. A small access port can serve both moisture

and pollutant absorbers.

Maintain the absorber. Renewal of activated charcoal is critical to prevent secondary

outgassing. To ensure continual filtration, both activated charcoal and potassium

permanganate must be replaced when exhausted.

4 D. EXHIBIT FABRICATION, INSTALLATION, AND MAINTENANCE

4.1 Case Construction Materials

4.1.1 Choosing Stable Materials

Use high-quality, non-hazardous materials close to objects, within case interiors, and

in exhibit furniture. Select high quality, conservation-safe materials; avoid materials

known to outgas, become acidic, or lose their physical or chemical stability. Consult

lists of materials that have been researched, talk with other museum professionals,

and test proposed materials.

Avoid adhesives when possible. If necessary within the object display area, use a

conservation-quality adhesive with a successful track record in exhibits, such as one

based on tested resinsacrylic, polyvinyl acetate, or certain high-temperature heat-

activated adhesives.


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Review the composition of commercial interior finishes. Select nonhazardous paints

and finishes, such as formulations based on 100% acrylic resin for wood or metal

surfaces and powder coatings for metal surfaces.

Allow sufficient curing time before installing objects. Approved caulk sealants andfinishes require a minimum of three weeks to reduce emissions.

Isolate objects from painted or varnished surfaces. Separate objects with a mount or

a layer of inert paper, foil, or other acceptable barrier, such as polyethylene or

polyester sheeting.

Select and attach decorative fabrics with care. Check fabrics for dye stability and

fastness; prewash and dry them before installation to preshrink and remove excess

dyes and finishes. Use a mechanical attachment method or sew fabric to itself;

archival-quality double-sided adhesive tape is useful for temporary exhibits.

4.1.2 Using Less Stable Materials

Use the least hazardous materials, and isolate objects from them. When problematic

materials cannot be avoided, select low-acid, low-outgassing, formaldehyde-free

products.

Seal or isolate all wood products. Apply barrier coatings, foils, or laminates to isolateraw wood and wood-composite surfaces that are close to objects, especially within

exhibit cases.

Aerate the case. After applying coatings and sealants, allow enough time for curing

before installing objects. A minimum of three weeks is recommended, with case

doors open and vitrine bonnets removed.

Isolate objects from problematic surfaces. Wood products, even when coated, must

not come into direct contact with objects. Physically isolate objects with safe fabric

coverings, acid-free paper or board, foil, or an acceptable plastic barrier such as

polyester or polyethylene sheeting.

4.2 Exhibit Fabrication, Installation, and Maintenance

4.2.1 Design and Fabrication of Exhibit Mounts

Design and fabricate mounts for object installation ahead of time. Use a qualified


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mounting specialist who has conservation training; some objects require the direct

involvement of a conservator. How an object will be displayed and what type of

mount is required are early design decisions.

Protect the integrity of the object. No object can be physically altered or dismantledto accommodate placement or mounting in the exhibit. Objects must not be drilled,

trimmed, tacked, nailed, taped, screwed down, or glued down. Use mechanical

designs to lock mounts in place.

Support the entire object. The object's center of gravity or originally intended

attitude should be considered when designing a mount. Support provided by the

mount must prevent physical stress or unbalanced weight distribution.

Provide adequate support for flexible objects. Create custom-padded mounts for

organic materials that support the structure over its entire contour. Textiles, papers,

organic materials, and other susceptible objects should not be creased or folded, nor

should heavy objects be placed directly on top of them.

Support all parts independently. Fragile objects, including textiles, should be

supported over as large an area as practical. Attached parts, such as straps, may

require independent support.

Stabilize objects from vibration. The mount design should reduce vibration when a

case is bumped. A cushioning material is often required. The mount should fit the

object evenly to prevent abrasion.

Ensure the security of framed works. Attach them to the wall with appropriate

hardware such as D hooks and braided metal wire. Anchor the wall fastener firmly

to the wall and be sure that it can support the weight of the framed object.

4.3 Exhibit Production and Object Installation

Avoid transporting objects into production areas. Ensure the safety of objects during

measurement and fitting sessions. Implement techniques to reduce, contain, and

collect dust in areas where objects must be transported.

Inspect exhibit assemblages that affect objects. Include several inspections during

the production phase to ensure that the preservation elements are built to

specifications. Test and approve exhibit cases with conservation features before

object installation.


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Complete construction before object installation. The exhibit area should be cleared

of debris and dust.

Evaluate the exhibit team's performance. Review the exhibit process and evaluate the

exhibit environment to assess how well the final product addressed the initialconservation concerns. Introduce any improvements and adjustments to the exhibit

process for the next project.

Provide a maintenance manual. Document the construction details, lighting, and

conservation features for future reference. Outline procedures and schedules for

maintaining the exhibit and conservation criteria for the objects.

Monitor exhibit conditions. Assign a staff member to inspect the objects daily. Any

controlled environmenteither in the overall exhibit space or in a casemust be

monitored to identify when maintenance is necessary.

Perform necessary maintenance. Replenish relative humidity and pollutant control

systems as needed. When replacing lamps, refer to the maintenance plan for the lamp

type and aim of the beam. Monitor light levels after the new lamps have been

installed.

Keep the exhibit area clean. A regular cleaning schedule facilitates preservation of

the objects and offers an opportunity to assess any change in the conditions of the

exhibit or the objects. Consult a conservator for appropriate methods and products.

Plan ahead for the safe movement of objects. During object rotations and inspections

or at the close of the exhibit, systematic removal of objects is necessary and requires

proper equipment. Before beginning demolition of an exhibit, ensure that objects are

carefully removed.

SUPPLIERS

Exhibit Conservation Guidelines, published as a CD-ROM by the National Park Service, can

be ordered from the Harpers Ferry Historical Association (telephone 800-821-5206); also

available from vendor University Products, Inc.

REFERENCES

NPS. 1999.Exhibit Conservation Guidelines: Incorporating Conservation into Exhibit


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Planning, Design and Fabrication; Harpers Ferry, WV.: Division of Conservation, Harpers

Ferry Center; CD-ROM publication; http://www.nps.gov/hfc/products/cons/ex-con-

guidelines.htm. U. S. National Park Service.

AUTHOR INFORMATION

TOBY RAPHAEL is a museum conservator specializing in exhibitions. He has served as an

exhibit conservation coordinator in countless exhibits nationwide, including the Ellis Island

Museum of Immigration, the exhibition of the Declaration of Independence at Independence

Hall, and exhibits at Lincoln's Birthplace, Manzanar, and the Selma to Montgomery March.

He has organized seminars and workshops on various exhibition/conservation topics for the

American Institute for Conservation, of which he is a Fellow, and for the National

Association for Museum Exhibitions, of which he is currently Conservation Advisor. In

1990 he was a Fellow at the Getty Conservation Institute; in 1993 and 2001 he received

Fulbright Fellowships to teach conservation in Latin America; and in 2005 he was awarded

an ICCROM Fellowship in Rome to create conservation standards for development of new

exhibitions. Address: PO Box 819, Shepardstown, WV 25443; [email protected]

Copyright 2005 American Institution for Conservation of Historic & Artistic Works

jaic 2005 - preventive conservation and the exhibition process

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