Shingo Hidaka

Continuous Efforts over 10 Years for Storage Re-organization at the National Museum of Ethnology, Japan

ABSTRACT The National Museum of Ethnology, Osaka, Japan, collects a vast amount of materials and information related to peoples’ life and culture, and makes them available to society through exhibitions and other activities. The number of collected items is increasing every year: 343581 objects have been collected from Japan and abroad as of March 2017. The continuous efforts have been necessary to improve storage conditions and to save space for both general and special storerooms. The former, which account for 90% of the storage capacity of the museum, are air-conditioned during working hours, with temperature and relative humidity (RH) settings varying with the seasons. The latter, which house objects for which strict conservation conditions are required, are air-conditioned for 24 hours with fixed settings of temperature/RH throughout the year determined by the nature of the materials from which the objects have been made or formed. Storage re-organization began with special storerooms, for which the number of objects and the storage area are far more limited in comparison with the general storerooms. The storage shelves for fur/skin/feather (almost 1000 objects) and for carpets (almost 550 objects) were all renewed in FY2007/2008. Then two large-scale innovation projects for general storerooms were conducted: construction of storage areas for ships equipped with a CO2-based and anoxic pest treatment facility (FY2015), and a complete refurbishing of the general storeroom for large objects (FY2016). Windows were set in the corner of this storeroom to provide visitors an opportunity to view and learn about the museum activities. In parallel to the above projects, daily storage improvement efforts have been undertaken. Storeroom No. 3, chosen as an example for general storerooms for small and medium-sized objects, was used to investigate the range of issues related to the shelving arrangement and storage conditions. Guidelines for storage re-organization were formulated according to the results of the investigation and according to the experiences gained through the renewal of special storerooms. Storage re-organization undertaken in storeroom No. 3 was conducted for 6 years at the rate of around 2000–4000 objects per year with a low budget and with reuse of existing shelves. In FY2016, all objects in storeroom No. 3 were properly redistributed. About 40% of the storage space was saved. Over these 10 years of storage re-organization, preventive measures have been taken for sustainable collection management. As early as FY1992, pest trap investigations have been carried out seasonally. Since FY2004, the results of investigations have been analyzed using a customized computer program. Subsequently, appropriate integrated pest management measures have been taken. In addition, since FY2014, energy-efficient air-condition control has been adopted for general storerooms. It consists of switching off air-conditioning in spring and autumn, and of starting it only when the temperature or RH values become too high in summer or too low in winter. Because the turning-off of air-conditioning causes comparable or even less climatic fluctuation, it was considered acceptable both economically and from a conservation perspective. It is estimated that turning the air-conditioning off during transitional seasons brings cost savings of about 3000000–4000000 JPY (about 26800–35700 USD as of 23 September 2017) per annum, which accounts for almost 30% of the electricity expenditures for all general storerooms.

Common challenges for ethnographic and modern art collections: Pest control for large and complex objects containing new materials

Introduction When it comes to pest control measures, ethnographic collections and modern art have to overcome a common challenge: the necessity of considering diverse and new materials. The National Museum of Ethnology, Osaka, Japan, has an extensive collection of artefacts from all over the world. Since the objects frequently contain organic or composite materials, pest prevention and control are inevitable. Many of the new acquisitions contain synthetic materials, therefore the effects of pest control measures on these modern materials have to be taken into account. After the proclamation of the Montreal Protocol on Substances that Deplete the Ozone Layer in 1989, the use of a mixture of methyl bromide and ethylene oxide, the then commonly used fumigant for cultural properties in Japan, was gradually reduced. When methyl bromide was totally banned in Japan at the end of 2004, pest control policies needed to be revised. Since January 2005 the National Museum of Ethnology has used ethylene oxide only for fumigation following quarantine, of artefacts collected abroad. Artefacts collected or travelling within Japan are treated with one of the alternative and more environmentally friendly methods, mainly by carbon dioxide (CO2) treatment, and complementarily by anoxia treatment, heat treatment, and freezing. Occasionally, objects are treated with a pyrethroid insecticide. This poster describes three case studies that illustrate how an appropriate pest control measure is selected depending on material, size, condition, and location of the artefacts.

Conservation Science Research at the Museum: Development of Carbon Dioxide Treatment for Museum Collection

The development of an enclosure-type insecticidal treatment for ethnographic/folklore artifacts using carbon dioxide is described. After the successful installation of the system, the technique was applied on a larger scale using a special enclosure-type bag (11.5 m in length, 10 m in width, and 2 m in height). Since one of the preconditions for development of the system was that the treatment procedures could be performed by museum staff, close attention was paid to worker safety. Other challenges faced were to: minimize the decrease in humidity inside the bag when carbon dioxide is supplied; achieve a uniform distribution of carbon dioxide concentration in a large-scale treatment facility; and establish supplementary methods for killing insects that resist by carbon dioxide treatment (e.g. longicorn beetles).

A New Evaluation Method for Paper Deterioration: The Rolling Test

Abstract: A new evaluation method for paper deterioration tentatively called the ‘rolling test’ is described. The paper to be tested is rolled using cylinders of different diameters, and paper which can be safely rolled on cylinders of smaller diameters is considered more “flexible”. The rolling test was shown to have a good correlation with artificial ageing. Correlation between conventional mechanical measurements and the rolling test was studied on paper samples of varying levels of degradation. While the formers are suited to the characterization of papers which are not much deteriorated, the rolling test revealed to be a more effective measurement method for artificially aged and weakened papers. The rolling test performed on a limited number of pages from the Kyocera Collection of British Parliamentary Papers (Kyoto University Library) showed that samples from the second half of the 1800s are comparatively less “flexible” than samples from the other periods. The analysis of the fibre composition suggested that the use of groundwood pulp was a potential cause of the deterioration seen in the papers of this period.