Assessment of indoor air quality and the risk of damage to cultural heritage objects using MEMORI® dosimetry

Air pollution is one of the environmental influences that degrade cultural heritage objects situated indoors. Other essential influences, such as temperature, relative humidity, and light are often well monitored. The presence of air pollutants is less often measured or included in risk assessment. The MEMORI^® technology presented in this paper was developed as a tool for easy measurement and assessment of the general risk of degradation of heritage objects situated indoors due to indoor exposure to air pollutants. MEMORI dosimetry was performed in locations belonging to English Heritage and Tate (both located in London) and the National Archives of Norway in Oslo, to assess air quality. The related damage risk for collection objects and the protection offered by display and storage designs was assessed. A high level of acidic effect was observed inside a number of showcases, and a high level of oxidizing effect was observed in some room locations. Relatively simple mitigation measures, such as constructing tightly sealed showcases using low emitting materials, installing active carbon absorbing media inside a ‘microclimate’ frame, and using cardboard storage boxes for paper, significantly improved air quality. Overall, implementation of such measures is likely to improve the preservation of objects and reduce conservation costs.     

Investigation of Fogging on Glass Display Cases at the Royal Ontario Museum

ABSTRACT

Shortly after a major renovation at the Royal Ontario Museum, it was noticed that the glass panels in many of the new display cases exhibited fogging or hazing on the surface, sometimes in very specific patterns. Cleaning removed the fogging temporarily, but it began to reappear within 12 months. An investigation of fogged glass panels in display cases was undertaken to understand the source of the fogging and to develop an appropriate cleaning method. This included the analysis of residues from glass panels in several galleries, and surface imaging and compositional analysis of glass panels. The fogging residues on the glass panels consist mainly of sodium salts of organic acids and inorganic anions. Sources of the sodium in the residues include air particulate matter and the glass itself. The organic acids and inorganic anions that form salts with the sodium cations likely originate from volatile organic compounds (VOCs) and particulate matter in the air. Examination of the fogging patterns on the glass panels revealed that the sodium salts grow on marks made during cleaning attempts and the manufacturing process. These cleaning and manufacturing marks contain greasy residues that encourage crystal growth. Because of the variation in surface cleanliness, panels with more cleaning and manufacturing residues appear to be heavily fogged while those with less may appear to be unfogged in the museum display cases. A cleaning protocol was tested on two of the glass panels, and was found to remove all traces of grease and fogging residue.     

The application of vapour-permeable synthetic membranes to the climatic stabilization of museum showcases

Abstract

This paper describes a novel technique to stabilize the relative humidity (RH) of the air inside museum showcases by using a synthetic hydrophobic membrane coupled with a hygroscopic solution in a membrane contactor. RH-monitoring data for two identical test cases, one of them controlled by a set-up with a plane-plate membrane contactor crossed by forced air and lithium chloride (LiCl) solution flows, show a significant stabilizing effect on RH fluctuations. A theoretical model permits forecasts in close agreement with the experimental RH data. Further calculations carried out over a one-year period show that notable damping of external RH variations can be obtained by using a low air circulation rate, small membrane surface area and low solution mass per unit case volume. A more general analytical solution in harmonic conditions is derived and discussed.     

Search,Serendipity, and the Researcher Experience

ABSTRACT

Lettie Conrad reported on the findings of original research on academic user experience with serendipitous discovery in scholarly research. This research has been released as the fourth installment of a series about discoverability as part of the SAGE White Papers. This research was designed to examine how students and faculty seek content beyond the search box. The researchers being studied take advantage of unplanned or unexpected content discoveries such as selecting a link in an e-mail alert, following a trail of citations within an important paper, or making use of recommendations. The study found that researchers decide to follow recommendations, either machine generated or from an acquaintance, based on a combination of perception of relevance to the field of study, access to the recommended article, and trust in the provider. SAGE has used these findings to enhance its products to better showcase content to users and then help them to more readily make sense of it.     

Conserving contemporary artworks: perspectives of artists and curators at the National Art Gallery of Zimbabwe

In fine arts, contemporary artists seek to showcase their artistic skills and concepts. There is very little awareness by most artists on the quality of materials they use in art production and the conservation needs of contemporary artworks which pose conservation challenges as materials used and the physical quality of artworks produced are secondary to what the artists seek to express. Of prime interest to them is the expression of concepts through various genres of art creation. However, the quality of material used by most artists is largely affected by their financial situation and inadequate knowledge on the durability of such materials. Artworks created using recycled materials such as found objects and cheap materials like poor quality paint on paintings, low grade paper in artworks, or poor quality wood present conservation challenges to professionals in galleries. The end product are artworks made from composite materials, some stable and unstable. Thus professionals are faced with a dilemma to reconcile the conservation needs of these artworks and the artists’ expression of their concepts. Moreover, in the absence of remedial conservation measures, artworks are prone to deterioration. This is worsened by dwindling donor and government funding which negatively impacts on the gallery's capacity to conserve the art. Additionally, conceptual expression, artistic creativity, and commercialisation of the art are of priority over conservation. Therefore there is need to maintain a balance between the need to express concepts and commercialise the art on one hand and to conserve the contemporary artworks on the other hand.     

Dimensional Stability and Moisture Properties of Gap-Fillers Based on Wood Powder and Glass Microballoons

ABSTRACT

Conservation of wooden objects exposed outdoors is extremely difficult and complex due to their constant exposure to fluctuating weather conditions and biological degradation. Filling the gaps in such objects requires the use of specific materials that in particular can adapt to changes in wood dimensions in response to humidity variations. Various materials have been used so far for filling voids in wooden artefacts but none of them was entirely suitable. Therefore, the authors have attempted to provide the basic characteristics of the selected commonly used filling materials based on pine wood powder or glass microballoons as fillers and Paraloid® B-72, Klucel® G, or glutin glue as binders, as the first step in research aiming at developing new and more appropriate gap-fillers. Special attention was paid to the dimensional stability of filling materials upon drying and exposure to water vapour and liquid water. The overall results indicate that among the examined fills those consisting of Paraloid® B-72 and glass microballoons revealed best properties as they were relatively dimensionally stable upon drying and exposure to moisture – despite high absorption of water – and were quite easy to finish. Generally, better properties were observed for filling materials containing higher concentrations of adhesives and these materials will be modified in the next step of the research. Since the main drawbacks of the examined gap-fillers were low water resistance, poor dimensional stability upon drying or exposure to water vapour or liquid water, and fragility or friability, future research into their modification will head towards improvement of the above-mentioned properties.     

Material characterization and preservation guidance for a collection of prosthetic limbs developed since 1960

National Museums Scotland has collections relating to many areas of science and technology, including medical science. This paper considers technical and conservation issues of an important collection of more than 150 prosthetic limbs. Much of the collection is of prosthetics developed for children born lacking or with malformed upper limbs caused by the prenatal morning sickness drug Thalidomide. However, many other examples are represented and the collection showcases a timeline of bioengineering development covering the past five decades. A wide range of plastics and metals were observed within the pieces examined, with many visibly degraded and degrading. The identification and characterization of these materials and their condition are fundamental to interpreting the development of the collection, for deciding on treatment, and for setting a strategy for future preservation. In addition to visual inspection, three analytical techniques were used to examine the various parts of the selected examples: Fourier transform infrared spectroscopy for polymer identification and condition; X-ray fluorescence spectroscopy to identify the metals and alloys present, and X-radiography to reveal the internal mechanisms of the limbs. Interpretation of the results was greatly enhanced by documentation and conversation with engineers and scientists involved in research and development of the limbs. The combination of different materials, some with conflicting environmental requirements, makes storage and display challenging as the goal is to prevent degradation of any part the object. Some objects were found to be actively degrading and for these separate storage solutions have been recommended to slow the emission of volatile degradation products that would cause further damage throughout the collection.     

When Glass and Metal Corrode Together,VI: Chalconatronite

ABSTRACT

Chalconatronite, Na₂[Cu(CO₃)]₂·3H₂O, is formed as a corrosion product when copper alloys are exposed to sodium carbonate solutions in the air. This also happens when metals come into contact with corroding soda glass which forms alkaline surface films in reaction with humidity from clean air. More often, substantial amounts of formaldehyde are present indoors which react to formate via the Cannizzarro reaction and accumulate over time in the films. Twenty cases of chalconatronite (including two mentioned in the literature) are reported as occurring on heritage objects with glass in contact with copper alloys: Baroque reliquaries with set glass gems, enamel on metal (sixteenth century and a modern replica of intentionally unstable composition), Christmas tree glass baubles with wires, glass buttons with metal shanks, a glass figure with a wire support, miners’ lamps, and a glass framed daguerreotype. These confirmed identifications might help conservators in investigating similar cases to shed more light on the formation conditions.     

When Glass and Metal Corrode Together,V: Sodium Copper Formate

A sodium copper formate, first described in 2002, can also form on copper alloys with sodium originating from soda glass hydrolysis. The frequent occurrence (50% of 250 cases of glass-induced metal corrosion) is due to the presence of formaldehyde emissions in storage and its direct reaction to formate in the alkaline surface films. The compound can be produced without the presence of acetate when chalconatronite or metal coupons immersed in soda solution are exposed to formaldehyde vapours. The crystal structure, derived from X-ray powder diffraction, yielded the sum formula Cu₄Na₄O(HCOO)₈(OH)₂·4H₂O. Except for the absence of acetate in the structure, this is in good agreement with the 2002 publication. To assess which kind of combined glass/metal objects are affected, a number of large museum collections were surveyed. Sodium copper formate was detected as a corrosion product using mainly micro-Raman spectroscopy, for instance, on 18 painted Limoges enamels, eight glass vessels with metal mountings, glass beads on metal wire from 11 bridal crowns, nine Christmas tree balls with wire decoration, 40 pieces of jewellery with glass gems, three daguerreotypes, and one miniature with cover glasses.     

Building Community: Partnering with Students and Faculty to Design a Library Exhibition Space

ABSTRACT

An academic library's space has traditionally operated as a repository, but with the proliferation of new media and interactive technologies, libraries now also serve as incubators of ideas. Architecture students at Auburn University recently took part in renovating the design library. With the librarian acting as client, they were asked to investigate diverse materials and design methods to create a dynamic and interactive exhibition wall which would showcase the creation of new knowledge and facilitate the dissemination of new information. This article discusses how the plug-in wall acted as a catalyst for the school's renewed communal investment in the library.     

Frontiers of Preventive Conservation

ABSTRACT

This work considers areas where our present lack of knowledge curtails the effectiveness or efficiency of preventive conservation practice. Mixed media, especially archaeological metals and organics have incompatible requirements for relative humidity (RH). An approach based on understanding the risk versus RH for both materials and considering the showcase performance is elucidated as a solution. Pollution, both the mixed atmospheres around most cultural heritage and the complex, variable nature of deposited particles, are further areas in need of more research. Damage functions and measurement of object deterioration rates are investigated as a path forward, and examples are given.     

Symbols of service: Oral histories of veterans tattoos as outreach

Outreach to special populations can be a sensitive endeavor, especially when the population, such as veterans, has a unique life experience in comparison to the general population. The use of oral histories for engagement and outreach can be a useful tool in making a connection to the veteran population because it gives them an opportunity to talk without being judged and the library a chance to listen. This case study highlights the collaboration between the library and the campus veteran center in an effort to come together and showcase veteran stories around their tattoos.     

Enhancing the case for Electronic Government in developing nations: A people-centric study focused in Saudi Arabia

The pace of implementing Electronic Government (E-Gov) is rapidly increasing. However, despite high levels of investment, a broad range of applications, and various methods of access relatively low levels of various methods of access, relatively low levels of usage (and even familiarity with e-gov) are still common. For example, in Canada, long recognized as a leader in implementing e-gov, less than 27% of Canadians used E-Gov during the past 12 months and 81% of c non-users report a low level of familiarity with either federal or provincial governmental services available through e-gov (Canada, 2004). Or, consider the showcase e-gov Gyandoot project in the Dhar district in central India, whose population is estimated at 1.7 million. Even after implementing e-gov in a showcase project for the rural poor, a study by the Center for Electronic Governance, Indian Institute of Management, Ahmedabad concluded that this model of “government to citizen” service delivery has serious sustenance problems (World Bank, 2004). The research reported in this paper takes a step back and focuses on the acceptability of e-gov by individuals. It is a people-centric approach to determine the overall acceptability of e-gov to people in a developing country, Saudi Arabia. Although this research may be generalizable to other situations, the primary intention of this project is to shed light on how to approach and manage implementation projects in developing nations.     

Data in conservation: the missing link in the process

Abstract

There is a missing link in the strategic introduction of new materials in conservation, which lies between the identification of new processes/materials and their widespread use in conservation treatments. Clinical trials to monitor the results of treatment success provide an effective procedure to evaluate the conservation process. This is now possible due to the increasing power and widespread use in conservation laboratories of computers, which provide an analytical tool for evaluating and examining treatments and procedures. Information, such as object condition, is routinely generated during the conservation of objects. To use this information statistically, it has to be structured to answer specific questions. Medical professionals have already established epidemiological techniques as a means of evaluating patient health and treatment performance. These techniques can be applied to conservation questions to provide statistically valid answers. This is an important tool with which to judge and prioritize strategies in the conservation process.     

Chemical air filtration in archives and libraries reconsidered

The implementation of chemical filtration in air-conditioning systems in archive and library repositories has become standard practice for heritage institutions in many countries. This practice is codified in official standards with general reference to a substantial body of scientific publications on the effects of air pollutants on paper materials. In this paper we report the application of a well-established decision analysis approach elaborating an integral cost-benefit perspective to provide decision support to four European national heritage institutions confronted with dilemmas in connection to chemical air filtration. Available scientific evidence for air pollution induced damage of paper material is reviewed and weighed against financial and environmental costs of air pollution control. Exposure of paper to both indoor and outdoor generated air pollutants at typical concentration levels observed within storage areas is expected to cause minimal to no additional yellowing and embrittlement, while the costs of chemical air filtration are significant. From a cost-benefit perspective the use of chemical air filtration in typical library and archive repositories is therefore discouraged.     

Real World Objects: Conceptual Framework and University Library Consortium Study

Expanding libraries' repertoire of relevant materials is one of the most important areas of concern for librarians. Incorporation of objects into library collections is an ongoing practice for which librarians remain under-equipped. Having a common language to discuss less conventional library materials across specialization areas helps libraries provide patrons with access to valuable informational objects. In order to provide access and preservation for objects, libraries need a conceptual framework, which is developed here. An observational case study was conducted to inform the reader of the current landscape of objects in libraries by sampling the websites and catalogs of a university consortium utilizing definitions established in the framework. The qualitative data from this study will be presented in a table after the framework is explored. This paper has implications for informational objects in every academic subject area, as well as for ongoing services in makerspaces and media centers.     

Disfiguring organic residues on industrially produced sheet metal coupons simulating copper and brass works of art by Donald Judd: Attenuated total reflectance Fourier transform infrared spectroscopy analysis and treatment recommendations

Abstract

The Minimalist work of Donald Judd exemplifies modern and contemporary works of art that utilize the appearance of bare metal as an integral component of the artist's intent. Decades after fabrication, disfiguring patterns have appeared on the surfaces of many such works. These patterns are not related to the formation of tarnish or other corrosion effects caused by improper storage, display, or transportation and handling; rather, they are associated with the initial processing of the metal sheets and subsequent fabrication of the art objects. Due to the challenges of obtaining analytical data directly from works of art, the authors present results from industrial sheet metal coupons prepared to simulate materials and techniques used in Donald Judd's copper and brass artworks. Attenuated total reflectance Fourier transform infrared spectroscopy carried out on each side of 55 coupons indicated the presence of organic materials such as long-chain aliphatic hydrocarbons, esters, and ethers, consistent with the types of compounds used in industrial lubricants. In addition to conducting the first systematic instrumental analysis of these residues, the authors propose the use of specific solvents for their removal as an alternative to abrasive methods, which cause removal of original surface from the objects.     

Link It or Lump It

Abstract

Mounting digital images of art objects on a Web site is only the first step in providing patron access to such materials. Libraries and museums have a responsibility to provide not only high-quality digital reproductions but also high-quality access from an integrated library catalog with controlled vocabulary and consistent access points. While some digital collections may have excellent internal searchability and require no more than collection level cataloging in a library's OPAC, others may demand cataloging of individual components of the collection. A particular collection's significance, its potential audience, the types of access required, as well as factors such as its size and cohesiveness need to be considered before becoming locked into a specific Web designespecially when it is that of another institution.

This paper examines several online library catalogs in which records for art objects as well as historical objects and natural history specimens have been merged, with varying degrees of success, and briefly addresses a modest proposal to catalog ceramic objects at the Ohio State University Libraries. The importance of consistent subject access in a merged catalog, regardless of the thesaurus or thesauri used, is stressed. Library consortia and bibliographic utilities may offer an economically appealing alternative for libraries that cannot design and construct their own digital libraries but these external organizations often have limited capability for-or interest in-modifying the design for a particular library and even less interest in cataloging the collections. Libraries, too, must be faulted for simply listing available electronic resources, either alphabetically or in broad subject categories, on a separate portion of their Web page and failing to provide full catalog records in their catalog. Finally, it is emphasized that the current debate over the viability of MARC 21 versus other metadata standards remains largely irrelevant to the importance of continuing to cultivate a monolithic online catalog, maintaining cataloging standards, and not mindlessly developing what amounts to a separate, rudimentary catalog solely for electronic resources.     

Influence of Process Parameters on Chlorinated Biocide Decontamination by li-CO2 on Artificially Contaminated Model Materials

ABSTRACT

Previously, heavy use of biocides for the treatment of objects made of organic materials in museum collections (e.g. ethnographic, historical collections) was very common. Now suitable decontamination methods/technologies are being sought. A decontamination treatment by li-CO₂ was optimized that considered the specific requirements of museum objects. The treatment was tested on model materials artificially contaminated with biocide solutions containing dichlorodiphenyltrichloroethane (DDT), pentachlorophenol (PCP), lindane, and permethrin or cypermethrin. High decontamination was achieved for DDT, lindane, PCP, and permethrin on artificially biocide loaded wool and wood model materials. Optimal process parameter settings for li-CO₂ decontamination include a single 30?min cycle for woolen materials and three sequential 30?min cycles each for wood. These methods allow a reduction of at least 90% of all biocides for wool and between 70% and 85% for wood. Decontamination of the latter was more effective for less polar biocides as DDT and permethrin. Despite a significant improvement in decontamination for wood using co-solvents such as acetone, ethanol, and methyl tertiary-butyl ether (MTBE), their use is not recommended due to the increased risk of damage to the objects, in particular if a surface coating is present.