Environmental Guidelines Opportunities and Risks

Fenella G. France, Preservation ScientistEric F. Hansen, Chief, PRTD

Library of Congress

How well do current environmental standards and guidelines align with

the conservation of heritage?

Attaining Standards: Assessing Risk

Existing Environmental Standards Recommendations and Guidelines (a selection)• British Standard BS5454: Recommendations for the

storage and exhibition of archival documents. • ISO 11799:2003: Information and Documentation –

Document Storage Requirements for Archive and Library Materials

• ANSI/NISO Z39.79-2001 ISSN: 1041-5653: Environmental Conditions for Exhibiting Library & Archival Materials

• NARA 1571: Archival Storage Standards• Library of Congress Guidelines & Specifications• Thomson, G., The Museum Environment• ASHRAE Chapter• CEN Guidelines

Goals

Standards should enable, not deter

From historic practice to heritage based

The underlying goal of best practice in environmental preservation is to attainoptimum conditions to protect cultural

heritage

This should be aligned with the specific material-based needs of the artefact

Environmental controls for preservation are long overdue for revision

The current economic, political & climate changes challenge standards to be

addressed in context of the above issues

Museums

Libraries

Archives

Historic Houses/ Buildings

Cultural Heritage Institutions: Convergence

Exhibition & Display

Storage: Immediate & Archive

Access: Public &

Researchers

Common Environmental Issues

The Environment: “Macro to Micro”Standards for cultural heritage in context:• The Building (historic architecture or modern)

– Building materials, – Cost of upgrade of structure & systems– Potential for retrofit

• The Room: Storage / Exhibition / Research– Collection type / material specific needs– Cost of humidification / mechanical systems (active vs. passive control– Level of access / zoning– Tolerance levels for materials– Separation of collection: material based vs. content based– Collection vs. human comfort

• The Case: Display / Storage (Visual)– Controlled environment (reduced energy costs)– Range of storage case control

The Building

Rooms: Storage / Exhibition /Research

Cases: Display / Visual Storage

Climate

Standards

Energy

Economic

Factors that Impact

Collections

Buildings: Historic, Modern (define modern), Customised

Knowledge

Where are we currently?

What do we need to define?

Establishment of recognized overarching need to control / limit fluctuating conditions

Standards state that temperature, relative humidity etc. should be at fixed points in a range

To promote longevity customized buildings andspecialized storage evolved

e.g. Library of Congress special storage modules maintained at a constant 10°C and 30% RH

Advances in knowledge of changes in materialsbased on scientific studies

Technology and engineering advances

Collection vs. Human Comfort

Issues• Maintaining and understanding the required

environment• Balancing preservation and access• Collection vs. human comfort• Utilizing technology and engineering advances

effectively– Linking with material properties– Increase access while preserving original

• Adapting standards and knowledge to local environments– Stable versus fluctuating

Gaps

Collaboration, Research, Future

Understanding of fluctuations and cycling for relative humidity of specific materials

Determining major cause of deterioration for specific materials

Differing requirements for materials & materials composites on exhibit, storage

Linking materials research with building control systems / level of control

Internationally agreed standards for cultural heritage buildings and collections

Incorporation of local climate adaptations based upon measured material properties

Whole Artefact

Area /Loss Fragility

Molecular or fibre level

Environmental Control RH, Temp etc.

Micro Changes Acceptable / Irreversible Damage

Damage Factor Tolerance Levels

Standards Impacts / Concerns: Materials “Macro to Micro”

Overview• Establish Advanced Knowledge of Materials Science

for Preservation– Tolerances & Actual Damage– Control of Damage Factors vs. Bulk Parameter

• International Materials Research Collaboration • Implementation of Standards Consensus /

– International loans– Enabling Optimum Protection of Cultural Heritage

• Reality: Achieving Preservation in Current Economic, Energy (mandates) & Climate Changes– Best Allocation of Resources (cost benefit)

• Preservation & Access linked to Damage/Risk• Risk versus Value Assessments

– What is Acceptable / Inevitable Loss