Risk assessment of Museum Amstelkring: application to an historic building and its collections and the consequences for preservation management Agnes W Brokerhof*, Tessa Luger, Bart Ankersmit and Frank Bergevoet Instituut Collectie Nederland (ICN) PO Box 76709 1070 KA Amsterdam The Netherlands E-mail: [email protected] Web site: www.icn.nl Robert Schillemans, Peter Schoutens, Tine Muller and Judikje Kiers Museum Amstelkring Oudezijds Voorburgwal 40 1012 GE Amsterdam The Netherlands E-mail: [email protected] Web site: www.museumamstelkring.nl Garnet Muething and Robert Waller Canadian Museum of Nature PO Box 3443 Station ‘D’ Ottawa ON K1P 6P4 Canada E-mail: [email protected] Web site: www.nature.ca *Author to whom correspondence should be addressed Abstract Museum Amstelkring is an historic building with a hidden church and mixed collections. It attracts many visitors and the church is still in use. The museum is concerned that it can no longer adequately balance preservation and presentation requirements. Instituut Collectie Nederland (ICN) was asked to give integral advice on preventive conservation, visitor impact and collection management, and to investigate whether building an extension to the museum might ease the pressure on the main building and create better opportunities for the collection. A complete risk assessment and other investigations were done to attach objective measures to perceived issues and quantify risks so that their relative importance could be determined. This approach enables museum management to prioritize and make reasoned decisions about improvements and investments. For museum staff it draws attention to weaknesses in working procedures while for conservation scientists it reveals issues that need further research. Keywords preventive conservation, risk assessment, preservation management, collection management, historic building, historic interior Introduction Museum Amstelkring, Our Lord in the Attic, is one of the oldest museums in Amsterdam, The Netherlands. It is a 17th century canal house with an interior that shows the splendour of the Dutch Golden Age. Looking like an ordinary house from the outside, visitors are highly surprised to find a complete church in the attic. This church – built at a time when Catholic services were officially prohibited – is one of the few hidden Catholic churches to have survived in its original state. The church building is the most important ‘object’ of the museum and is still used for special masses, weddings and concerts. The moveable collections consists of some 10,000 objects, ranging from 17th century furniture to paintings, catholic artifacts, books and archives (Figure 1). As such Museum Figure 1. Exterior and interior of Museum Amstelkring, Our Lord in the Attic (photos: Gert-Jan van Rooij) Amstelkring keeps a building and a collection which tell the story of faith despite social exclusion. It is a story of inventiveness and perseverance but also of society’s tolerance. In any social or religious context, the story of acceptance of those who think differently forms the basis for keeping and preserving collections. The mission statement of Museum Amstelkring describes a task that consists of two conflicting parts: preservation of the 17th century canal house, the hidden church and the moveable collections on the one hand and providing accessibility of the monument for visitors on the other hand. There is a growing tension between these two. With visitor numbers increasing from 42,000 in 1992 to 70,000 in 2003 museum management has the feeling that it can no longer adequately balance preservation and presentation requirements. Climate conditions in the building are not optimal while the services provided to visitors do not meet current museum standards. Yet, a mere feeling is not a strong argument in discussions with the museum board, city council and financers when looking for improvements. Therefore museum management decided to substantiate the feeling and systematically study the needs for improvement. The Instituut Collectie Nederland (ICN) was asked to give integral advice on the issues of preventive conservation, visitor impact, and collection management, and to investigate whether building an extension to the museum would significantly ease the pressure on the main building and create a better environment for the moveable collection. Research methods The primary concern of the museum staff is the issue of visitor impact. The most striking example is the wear and tear of the original 17th century staircase which had to be closed off to the public to stop further damage (Figure 2). To gain insight into visitor impact and to weigh this risk against all the other risks that threaten building and collections, a complete risk assessment was done. It was considered important to investigate whether visitor impact is indeed the biggest threat to the building and the collections, or whether this is just a matter of perception. The integral approach of the risk assessment has acted as a safeguard against focusing exclusively on one issue. Another important feature of this risk assessment is that it dealt with moveable as well as non-moveable collection units. The reason for this is the fact that the building and its historic interior are considered to be an essential part of the museum. In addition to the risk assessment, other research methods were used. A visitor appreciation survey revealed shortcomings in services, desires to be met and bottlenecks to be dealt with. Interviews, tours of inspection, temperature and relative humidity (RH) measurements, and survey of the documentation provided insight into the entire context of the museum. The diversity of research methods called for an interdisciplinary team, in which the input of the museum staff was indispensable. They were able to provide important information on the value of the collections and their use. The restoration architect contributed his knowledge about the building. The conservation scientists provided knowledge about interaction of materials with their environment. All of that combined enabled the consultants to translate the outcomes into collection management advice. Risk assessment Methodology The risk assessment was done in cooperation with the Canadian Museum of Nature using the ‘Cultural Property Risk Analysis Model’ developed by Waller (2003). All risks were divided into ten generic risks: physical force, fire, water, criminals, pests, contaminants, light/ultraviolet (UV), incorrect temperature, incorrect relative humidity and loss. These generic risks were subdivided into three types each: type 1 being rare but catastrophic, type 2 being sporadic but intermediate in severity, and type 3 being constant but mild. For each of the ten generic risks and their three types, relevance was considered. Earthquakes and Figure 2. Damage after 350 years wear and tear of the 17th century staircase cyclones for instance (physical force type 1) do not occur in Amsterdam; water spillage during maintenance of humidifiers (water type 3) is relevant. A list of 58 relevant specific risks was compiled and for each of these a scenario of events causing damage was described. Collection units and values To facilitate calculation of risks the building and collections were divided into collection units to assess. The moveable collection units were paintings, wood sculptures, furniture, textiles, nonmetal inorganic objects, books, metals, works on paper, ancillary/archives and composite objects. The non-moveable collection units were windows, doors, walls, floors, ceilings, stairs, the organ and architectural elements. For all collection units, relevant quanta were defined and the quanta were counted or measured. As examples, objects were quantified by number, windows by square metre of glass and stairs by number of steps. In a brainstorm session the values of the various units and their quanta were discussed. All have cultural and artistic value, most have historical, documentary and educational value. The historical value of the non-moveable units and the objects still used during services and events, conflicted as usual with the functional value. Considering loss of the various values due to different risks stimulated the debate about the relative importance of values. Confrontation with loss led to the appreciation of possession. At the start, the main value of the wooden floors was their function to carry people and thus their structural integrity was of prime concern. One could see that wear and tear had caused considerable loss of material in time and had required replacement of floor parts. This led to the realization that it is not advisable to just stick to this view. At the same time, however, it raised the question how original the floor actually is. Replaced floor parts tell their own story (Figure 3). Assessing risks For each combination of collection unit and specific risk, the magnitude of risk (MR) was calculated. First the fraction susceptible (FS) within the unit and the maximum loss of value (LV) of that fraction due to the specific risk were determined. Then the probability (P) of the scenario taking place within a century was determined. Finally the extent (E) to which the specific risk will affect the fraction susceptible and result in loss of value was determined. MR was then calculated as the product of these four parameters. The MR-values of the specific risks for the various units can be added within a generic risk to give the overall impression of the collection loss over a century due to that generic risk. These are not precise figures, but they give a good impression of relative magnitudes and enable internal comparison (Figure 4). Figure 3. Wear and tear of floor and replaced parts telling their own story Figure 4. Graph of MR values (z-axis) for all generic risks (x-axis) for each collection unit (yaxis) Results The risk assessment showed that for both building and collection Fire type 1 and 2 calculated based on equations of Harmathy et al. (1989), came out as the biggest risks. However, these figures were based on general statistics, which show a high probability of fire spread in buildings without a sprinkler system. The museum is aware of the fire risk, has strict procedures, and it was felt that, for these reasons, these risks are actually lower than that calculated for a typical ‘educational’ building. This shows that, at least in The Netherlands, fire incident registration and statistics in museums are lacking. Collecting better museum statistics would enable more accurate assessment of type 1 and 2 risks. The initial cause for concern, wear and tear due to visitors (Physical Force type 3), proved to be a high risk indeed when looked at more objectively, especially for stairs and floors. Here the conflict between history and structural integrity was most obvious. An important question is how much loss of material is considered acceptable and in how much time. Museum management is faced with a dilemma: it wishes to let as many visitors as possible experience the museum in all its facets, but at the same time, it wants to preserve the building’s authenticity. For each solution to lower the risk of wear and tear of stairs and floors, the consequences for functional, historical, ensemble and authenticity values has to be weighed. This can be done by either weighing the value or calculating the loss due to intervention options. Covering the wooden floors (with carpet or transparent boards) seriously intervenes with authenticity, esthetical and ensemble value. Applying lacquer to the floor is a huge intervention in material integrity. Another relatively high risk, both for the building and the collections, is damage as a result of internal transport of objects and repair and maintenance activities in and around the building (Physical Force type 2). Temporary exhibitions are an important instrument to present more in-depth aspects of the collections and the stories it has to tell. Therefore, the museum has an active exhibitions program, yet it has very little space for exhibitions and events. Each exhibition or event requires moving of objects and causes damage to the building as a result of installation. Storage rooms are overcrowded and hardly accessible, which also contributes to the risk of physical damage. Addition of a new wing to the museum with space for temporary exhibitions and sufficient room for packing, transit and storage, would significantly reduce all these risks. This outcome could have been predicted, but the risk assessment made clear that actually both building and moveable collections are fully exposed to these risks and that a substantial reduction in risk can be achieved through a building project. The risk assessment also dealt with the issues of climate conditions and light. As was expected, the risks of incoming sunlight and UV radiation (LUV type 3) and incorrect RH and Temperature turned out to be relatively high, even though a less strict regime was accepted than the currently used guidelines in The Netherlands. These problems are not easily solved since many necessary measures would involve the violation of the historical value of the building. A possible solution would be to move the most fragile objects out of the main building to an extension, where better conditions can be created. Given that heating of the museum in winter requires humidification with portable equipment, which involves a risk of water spillage and condensation on cold walls, it is worth considering accepting a lower average winter temperature at the expense of visitor comfort. As climate control systems cannot be installed in the building the possibility of forced ventilation under the roof will be looked into. The issues of microclimates in show cases and certain parts of the building, and the effect of large groups of visitors on temperature and RH still need further investigation. Two risks that turned out to be relatively high are connected with the level of internal organization and collection management. Pilfering by employees (Criminals type 3), came out as a much higher risk than had been anticipated. It is high not because the staff are considered so inclined, but because the ‘opportunity that creates the thief’ is present. The good atmosphere with much mutual trust goes hand in hand with a lack of internal control. This is recognized and confirmed by staff, which facilitates setting up stricter procedures without creating an unpleasant working environment. Loss of written and unwritten information about collection and building, owing to loss of documentation, memory-loss or change of personnel, scored high (Loss type 1–3). Although it is common practice to record historical data and conservation treatments of the objects this has not been the case for the building. These two risks could easily be mitigated in the present situation by introducing stricter procedures for handling objects and keeping records of all the work that is being done on the building. Interviewing maintenance staff and recording their knowledge may reveal valuable information about the building and its restoration history. Improvement options The advice and recommendations that were put forward in the final report, based on the risk assessment, interviews, inspections and environmental monitoring, could be divided into (1) improvements that can be made in the present situation, (2) improvements that can be realized by building an extension to the museum and (3) issues that need further investigation or research. The first type of improvements is being incorporated in the policy plan and work plans for the near and longer future. Because several of them hardly require financial investments, they can easily be implemented. Examples are designing procedures for access to storage areas, handling objects and keeping records of building maintenance. Encouraged by the awareness that the damage to the building caused by installing exhibitions is rather extensive, money was spent on a new system of clamp-fit moveable frames to attach small display cases, information boards and lighting systems. This has reduced the need for drilling holes in walls and ceiling (Figure 5). The second type of improvement is being used to found the feasibility study for the extension plans. For example, the options for improving the environmental conditions in the historic building are limited, but they can be realized in a new building. The risks to susceptible objects on display due to incorrect RH, temperature and lighting can thus be lowered. Meanwhile extra exhibition space is created which lowers the risk of damage to the building each time temporary exhibitions are being installed while the character of the 17th century interior is kept intact while temporary activities take place. Extra storage space and adequate access can be realized reducing the physical force type 2 risks. Also better visitor services can be offered with front desk, proper cloakroom, cafe, toilets and the museum shop, which means a big improvement compared with the heavily congested reception area of the historic building. An auditorium and an education area ease the pressure that presentations, events and the school tours put on the church. A second, hypothetical risk assessment for the new situation should be done to make a comparative risk– cost–benefit analysis for the extension. Several issues need further investigation. For example, apart from the obvious physical damage, it was difficult to link other risks to the number of visitors. More detailed monitoring of the climate inside the building, related to both outside climate, visitor numbers and airflow through the rooms has to be carried out before the complex interactions can be modelled and understood. In some instances the data needed to assess risks properly just is not available. The interaction of various materials and objects with the specific risks needs further research. Sometimes the uncertainty in estimated risks is still very large and further research is required to narrow the uncertainty and enable a better quantitative assessment. Side effects of the risk assessment An important step in the process of consciousness-raising proved to be the attribution of values to building and collection units and the fact that they can be attributed from the perspective of the museum, of the visitor, of the city and of the community at large. The discussions revealed the full value of objects as the sum of the values from individual perspectives. Thinking about loss of value in the risk assessment opens one’s eyes to the relative importance of the different values. Interestingly, the building gained overall value as a result of making the various values explicit! Figure 5. Clamp-fit frames for temporary displays put an end to drilling holes in walls and ceilings (design: Theo Tienhoven) Carrying out the risk assessment also increased awareness of the current condition of building and collections. In some instances the condition of objects was actually better then expected after more than 300 years in use and on subsequent display. In other instances weak spots in objects and building were revealed. Even though results from the past are no guarantee for the future, the current condition of collection units provided much information for the risk assessment parameters ‘probability’ and ‘extent’, while observed damage served as a guide in the determination of ‘fraction susceptible’ and ‘loss of value’. Describing risk scenarios focused attention on handling of building and collection units. The risk assessment also increased the awareness of the importance of documentation in both word and image. Documentation of information lays down the basic values. The risk assessment actually served as an instrument to internalize the collective knowledge about the building and the collections. As such it raised the level of professionalism of museum staff. Finally, doing the risk assessment and being so intensely occupied with collecting all available data to feed into the model’s equations, proved to be a team-building experience. Even though it is a time-consuming exercise that requires much commitment from everyone involved, it is highly rewarding. Being the first museum in The Netherlands to follow the systematic approach of the risk assessment and including the building as a full part of the museum collection attracts attention in the Dutch museum world. It shows how seriously a medium-sized museum deals with its problems and how efficiently it can do that. Conclusions The integral approach to the problems of Museum Amstelkring has helped to view all the problems in connection with each other. It has made clear which improvements can be made to the present situation in the short-, mid- and longterm and these will be incorporated in the work plans and adjusted procedures. It has also revealed which problems require a long-term strategy. The risk assessment has focused attention on all the possible risks in their integral context. Simple awareness of risks is, in itself, the beginning of reduction. The assessment has added insight into the relative magnitude of the various risks, thus enabling prioritizing actions for improvement. It has made it possible to identify the risks that are linked to visitor impact and the ones that are not. Comparison of these risks places visitor impact on the building and the collections in the proper perspective. Thus the instinctive concerns have become more objective. A complete assessment forces one to take the less obvious risks into account and to see possible relationships between risks and the combined influences of their various causes. Defining values of non-moveable collection units and thinking about the loss of value due to, for example, a scratch on a door was a very interesting exercise. Including the building in the assessment has led to a more conscious appreciation of the building. Building an extension to the museum could prove to reduce more than only the visitor related risks. A hypothetical risk assessment for the situation after building the extension provides semi-quantitative arguments in the negotiations with financers and decision-makers. Altogether the risk assessment of Museum Amstelkring turned out to be an important tool for both consultants and museum staff. The assessment has made clear where scientific knowledge is needed to enable proper calculation of risks rather than best guesses. It points out where further research is needed, such as into susceptibility of materials and dose–effect relations, especially in the area of temperature and relative humidity. Also the impact of visitors on the indoor environment needs more study. Overall, both Museum Amstelkring and ICN feel that by taking one step back from the details and looking at the bigger picture, they have taken a large step forward in preventive conservation and collection management. Acknowledgements We thank all those involved in the risk assessment, especially Frank Ligterink and Birgit Reissland (ICN), Annemiek van Soestbergen, Thijs Boers and Pjotter van Leeuwen (Museum Amstelkring) and Frederik Franken (Bureau voor Bouwhistorisch onderzoek en Restauratie). References Harmathy, T Z et al. 1989, ‘A decision logic for trading between fire safety measures’, Fire and Materials 14, 1–10. Waller, R R, 2003, Cultural Property Risk Analysis Model: Development and Application to Preventive Conservation at the Canadian Museum of Nature, Acta Universitatis Gothoburgensis, Göteborg, Sweden.