Conservation at the Weltmuseum Wien

The Conservation Department is responsible for the preservation, conservation, investigation and display of the museum’s collection. The department has grown to encompass five areas of conservation expertise, these are paper, textiles, objects, preventive care and research. The team comprises conservators, technicians and interns.

At the Museum of Ethnology the Conservation Department was established in 1955 as a chemistry laboratory with the aim to unite the art of restoration with the material science. Dr Wilhelm P. Bauer, a chemist, was appointed for this role. His contribution to the development of the conservation of ethnographic collection at the museum is greatly acknowledged and his story still needs to be written.

In 1968 the laboratory was expanded into a conservation workshop with one staff conservator with an academic training. Over the years the team grew and specialisations were acquired in organic and inorganic materials. After a major renovation of the museum in the 1990s, the Conservation Department moved to its new modern conservation labs of about 300 m² in size.

From the perspective of object conservation, the seemingly endless spectrum of different materials is divided into organic – wood, bark, plant fibres, skin, leather, feathers, horn, ivory, plastic etc. – and inorganic materials – metal, stone, ceramic, glass etc. The conservators examine and evaluate the material-specific alterations and corrosion processes of the objects. After the state of preservation is meticulously documented, the artefacts are subjected to various measures of conservation and restoration to either protect them from further damage or minimise any damage that might have occurred in the past.

Several preparatory steps must be taken before any of these procedures can be performed:
First the object is examined for its materials and manufacturing techniques – often in collaboration with the Conservation Science Department of the KHM-Museumsverband as well as other institutions – and its state of preservation is documented both photographically and in writing. The results are also of significant value to art-technological research. Any new information than can be obtained is entered into the database of the Museum. The conservators work with the curatorial team to learn more about the object’s cultural significance and original function, which enables them to consider the historical context in practical conservation. In some cases, it is even possible to enter into a dialogue with representatives of the object’s country of origin to coordinate a joint approach of preservation. The resulting conservation concept takes into account all the information on the planned use of the object (e.g. temporary exhibitions, permanent exhibition, loan etc.) and serves as the basis of any subsequent conservation and restoration measures.

An integral area of responsibility is the care and maintenance of exhibitions and loans, which includes the development of conservation quality standards, expert opinions on loans, preservation state documentation, the supervision of packaging, and courier trips.

Measures of preventive conservation are designed to continuously monitor and improve the conditions for collection objects inside the depot (ca. 3,800 m²). This applies to various parameters, such as relative humidity, temperature, lighting, pest control pollutants etc.

In cooperation with universities, the conservators also extend their services to offer internships and advise diploma theses in their respective field of specialisation.

In terms of the Weltmuseum Wien’s reopening, the department’s main task for the years 2016/17 includes planning the display cases, developing an object mounting plan, and carrying out the conservation and restoration of about 3,200 objects for the new permanent exhibition.

In the field of textile conservation, the daily routine of the conservators is primarily characterised by collection and depot maintenance, conservation and restoration, and the presentation and mounting of exhibitions.

Every object has many different stories to tell: about its making, materials, techniques, everyday use, trade, transitions, estimation, care, repairs, changes, times of neglect in humid or infested places, varying exhibition practices, and on foreign, older, and own cultural phenomena. The great passion and yet challenge of textile conservation lies in recognising, documenting, storing, and passing on all this information.

Collection care and preventive conservation measures in the depot for textiles:
Refurnished in 2013, the depot for textiles accommodates ca. 600 m²of usable space for about 15,000 textile objects. This is the home of small tissue fragments, accessories, containers, clothes from all over the world, larger hangings textile furniture, carpets, or part of tents. All objects are woven, felted, braided, netted, knitted, sewn, coloured, embroidered, printed … and usually decorated in countless ways.

There is a lot of work involved in conducting research, taking pictures and documenting the objects, improving the conditions for storage, climate, and pest control, and registering and caring for new acquisitions.

Conservation and restoration:
In the workshop for textile objects, there is a central area with large tables to prepare selected objects for exhibitions: such preparatory work usually means cleaning, smoothing, and forming the object, especially if the previous storage resulted in folded or crinkled sections, which would otherwise affect the “legibility” and aesthetic of the exhibit.

Any damages need to be repaired by means of adequate support and sewing measures. The right kind of thread or textile material is often dyed in the “wet area” of the workshop. All these steps of object conservation can only happen after the careful examination, damage documentation, and sometimes scientific analysis in collaboration with the respective collection’s curator, which in turn means that a significant share of the work time is spent at the computer.

Presentation and exhibition mounting:
Each new exhibition, especially the new permanent exhibition of the Weltmuseum Wien, demands a great deal of ingenuity, manual skills, and creativity from the team. Among the typical challenges is the development of virtually invisible bases for floating or moving presentations of textiles with minimal tissue damage. There is hardly a textile object that could be mounted without a protective and supporting base, sophisticated “circumventions of gravity”, and hidden measures for light and dust protection. Quite often, the limited exhibition budget makes it necessary to strive for a compromise in the interests of object preservation.

A wide range of artworks are in the care of the paper conservator including drawings in all media and techniques, prints, manuscripts, paintings and albums, photographs as well as plant-based writing materials and artefacts made from bark. This includes barkcloth that can be made from a variety of plants and is one of the world’s oldest non-woven fabric, providing a link between paper and textiles. In addition, many composite objects, consisting of other materials besides paper or materials with a paper-like qualities, are in the care of paper conservator.

This crossover between the material types and conservators specialisations reflects the collaborative approach to conservation of the team. Such approach ensures that complex and composite artefacts receive the most appropriate long-term conservation care.

While conservation treatment is often necessary to allow artworks to be exhibited, where possible, the collections are preserved by reducing the potential for deterioration rather than through treatment and repair, the preventive conservation methods are applied in preference to interventive conservation treatments. This approach is applied to the work of external contract conservators who assist in special exhibition-focused projects.

Improving the storage of paper based artwork is one of the core activities of the paper conservator. Surveying the collection and understanding the needs of individual artefacts or collection of items is the key to making customised solutions. These decisions are taken in consultation with museum curators.

The correct handling of the objects is of utmost significance for their preservation. Absorbent material such as paper and particularly sensitive photographic materials are easily contaminated. Traces of sweat, oils or dirt cause chemical changes that are often only visible on the object after a period of time. For this reason, particular attention is given to simple preventive protective measures such as protective covers, supporting materials and passepartouts.

Preventive conservation can be defined as all the actions taken to minimise or slow the rate of deterioration and to prevent damage to collections. It includes activities such as risk assessment, development and implementation of guidelines for appropriate environmental conditions for storage and exhibition, procedures for handling, packing, transport and use, and integrated pest management (IPM). These responsibilities are shared by the collection team, conservators, technicians, curators, facility management and other museum specialists.

Environmental factors that can damage collection items include light, temperature, humidity, pests, volatile organic compounds, airborne pollutants, shocks and vibrations.

Climate
The Neue Burg in the complex of the Hofburg Palace was originally planned to house the new living quarters of the imperial family (building work began in 1881 and partially finished in 1913). To provide a high level of living comfort, an innovative heating and ventilation concept, developed by Carl Böhm, was implemented. Air heating, with air supplied from outside, provided warm temperatures during winter, while the second basement level was explicitly constructed as an „air well“ (Luftbrunnen) to establish a higher level of air quality in the living rooms in the summer.

As part of the new opening of the Weltmuseum Wien, the historical „air well“ system was improved in order to establish a higher level of air quality in the museum.

Basics of a conservational operations concept for the Neue Burg in Vienna
by Dr. Alfons Huber

In collaboration with the climate specialists, ASHRAE environmental guidelines were chosen for the historic Neue Burg building, with the aim of refurbishing original historic air channels and using passive methods of environment control. The climate in the storage areas and exhibition galleries is subject to seasonal changes in air temperature and relative humidity. Exterior metal blinds and interior climate buffer areas between the exhibition galleries will facilitate a stable climate. Artefacts that are extremely sensitive to fluctuations will be stored in conditioned display cases or in climate controlled storage units. Artefacts that are at risk of damage by the fluctuating climatic conditions, these are collections of ivory, Asian lacquer, metal, leather or fur, are kept in storage areas equipped with climate control systems.

Light management
The balancing act between preserving and exhibiting artefacts is challenging. Light causes permanent and irreversible damage that affects the chemical composition, physical structure, and the appearance of the collection item. Common examples of damage from ambient light include: faded inks, yellowed paper, colour changes and fading of textiles, dark and brittle materials.

For this reason, it is important to define the duration of the exhibition display, the light intensity, and the value of a light-sensitive artefact.
There are two possible routes to reduce the potential damage from light – reducing the amount of light in a space and reducing the overall amount of time that the artefacts is exposed to light.

Not all materials are light-sensitive and guidelines exist concerning the expected light-sensitivity of materials. In this regard, the ISO Blue Wool Scale (BWS) is used by conservators as a reference. The scale consists of eight textile strips, with each previous strip being three times more light-sensitive than the following one. The majority of plant materials, many natural dyes and lacdyes, early synthetic dyes and coloured photographs are extremely light-sensitive (ISO BWS #1, #2, #3). Some feathers, furs, leather or natural fibres also belong to this category.

Often the guidelines do not adequately reflect the actual light-sensitivity of a specific artefact. Therefore, in situ spot tests have been developed such as microfading, that is a non-destructive and artefact-specific method of testing light sensitivity. The microfader exposes a submillimeter section of the artefact’s surface to very intense UV free light and uses a spectrophotometer to measure the light reflected by the irradiated spot in real time of exposure.

For the new exhibition, which is planned to be on view for the next 10 years, light sensitivity tests have been carried out on selected textiles and works of art on paper. Because of the light sensitivity, certain artefacts will only be displayed as reproductions; others will be rotated after a specific number of lux-hours (lux = unit of illuminance), or will be technically protected by touch sensors.

Integrated Pest Management
Integrated Pest Management (IPM) at the Weltmuseum Wien has been established since 2002. IPM is a preventive, long-term, low toxicity means of controlling pests. When applied in the museum context, it employs a variety of techniques to prevent and solve pest problems without compromising the safety of collections, museum staff and visitors. This programme is instrumental in preventing damage to our significant collections made from vulnerable organic materials that are most at risk from pest infestation – paper, textiles, objects made from wood, fur and feathers, leather and plant materials. While not often directly consumed by most pests, inorganic objects (eg. stone, metals and ceramics) can be damaged by general dirt and staining caused by pests.

Preventive measures are applied to all areas of the museum environment, these are the building, the exhibition and storage rooms, the exhibition and storage cases, and the actual objects themselves. The first step in an IPM plan is to prevent pests from accessing the collection by maintaining an environment that is not hospitable for pests. We make sure that collections areas are kept clean and free of debris and foodstuff that could encourage pests. Pest infestations can often be directly related to temperature and relative humidity. We work to ensure that collection areas do not have high heat or humidity conditions that will allow pest populations to flourish.

Monitoring the ecosystem of our building provides a useful way to determine the pest species common to our facilities. Insect traps, such as sticky traps and pheromone traps, are placed throughout the collection areas and checked on a regular basis. Identification of pests and evaluation of their potential danger to the collection allows decisions to be made on their elimination.

For both, preventive and quarantine purposes we use two treatments of pest elimination, these are controlled low temperature treatment, also known as ‚freezing’ and anoxic treatment (the elimination of oxygen from a microenvironment).

The duties of the conservation technicians are very diverse. Of great importance are the practical handling of the objects in exhibition and storage areas, and all aspects of transportation. Collection technicians also assist in creating ideal conditions for the objects' preservation and storage. All of this is carried out in consultation with conservators and curators, employing creativity, technical skill, capacity for teamwork, organisational talent and, above all, a great sense of responsibility for the objects.

Packing/Moving/Transport:
At first glance, the transportation of objects appears to be a very simple task: the object is moved from „A to B“. Yes, this task involves a great deal of planning and organization, the size and the various materials of the objects to be transported increase the complexity of the task. For example, large objects are stored at the central storage of the KHM-Museumsverband. Already one year ahead of this, the availability of adequate space in the central storage has to be discussed. The registrar records the appropriate location for the objects with the following details: room / rack / shelf. This information is stored in the museum database and printed on labels, which are attached to the object.

Ahead of transportation, objects must be safely and carefully packed and supported. Fragile objects require additional supports and mounts to prevent the damage. Large objects do not always fit through the doors of the museum. In these special cases, a freight crane must be used to lift the object.
Even then, however, the work is not yet finished: very often the objects have to be quarantined for possible pest infestation before entering the storage.

Object Storage & Housing
Another area of responsibility is housing of objects at the main storage of the Weltmuseum Wien and the external depot in Himberg. Here the objects are stored according to their origin as well as their relative humidity requirements. Collection manager and collection technicians monitor the environmental conditions, maintain the climatic equipment and assist in setting up an Integration Pest Management (IPM) system.

Object Preparation
The collection technicians assist conservators and curators with the installation of the objects on exhibition display. This includes designing and manufacturing protective supports and/or enclosures for objects, installation; preparation also may involve materials testing and environmental control.