| ■Tokyo National Research
Institute for Cultural Properties |
■Center for Conservation
Science |
| ■Department of Art Research,
Archives and Information Systems |
■Japan Center for
International Cooperation in Conservation |
| ■Department of Intangible
Cultural Heritage |
|
Oral presentation at Stone 2025
Study tour: visit to Notre-Dame Cathedral
From September 8 to 12, 2025, Dr. MIZUTANI Etsuko (author) participated in the 15th International Congress on the Deterioration and Conservation of Stone (Stone 2025), held at the Sorbonne University in Paris, France, and delivered an oral presentation. This congress, which takes place every four to five years, is an international forum on the conservation and restoration of sculptures and architectural structures made of stone and brick.
The congress brought together a wide range of participants, including conservation scientists and geologists studying the deterioration of stone and brick, practitioners involved in conservation and restoration, and experts in architecture and building physics. Presentations covered diverse topics, from fundamental studies on deterioration caused by air pollution and salt weathering, to new restoration techniques and practical conservation measures, as well as sustainable environmental control strategies and the evaluation of climate change impacts.
In her presentation, the author reported on research conducted at the Center for Conservation Science, Preventive Conservation Section, which focuses on improving the humid environment inside a rock cave housing a Buddhist wooden architecture, without relying on air conditioning, to preserve the structure. Following the presentation, the author received many questions and comments from researchers engaged in the preservation of cultural properties facing similar high-humidity challenges and others interested in sustainable environmental control. This provided an opportunity to exchange views on the potential for future collaboration.
Going forward, the author intends to continue actively disseminating research outcomes internationally, while also gathering the latest knowledge from around the world to further contribute to the preservation of Japan’s cultural heritage.
Scene from a research presentation in GCI
Scene of researcher exchange
As global warming has become a pressing global issue, the need for sustainable environmental management in cultural heritage preservation has also gained importance. In 2014, a joint declaration was issued by the International Institute for Conservation of Historic and Artistic Works (IIC) and the International Council of Museums – Committee for Conservation (ICOM-CC), calling for environmentally responsible approaches to preservation practices. At the Center for Conservation Science, Preventive Conservation Section, we have been pursuing research to explore sustainable environmental management methods suited to the preservation of cultural properties in Japan.
As part of these efforts, in August 2023 (Reiwa 5), a team from the Tokyo National Research Institute for Cultural Properties (TOBUNKEN) participated in the “Changing Climate Management Strategies Workshop: Sustainable Collection Environments and Monitoring Object Response,” co-hosted by the Getty Conservation Institute and The National Gallery of Victoria in Australia, and since then have continued exchanges with researchers at the Getty Conservation Institute.
From September 24 to 26, 2025 (Reiwa year 7), we visited the Getty Conservation Institute in Los Angeles. Two years after the workshop, members of both TOBUNKEN and the Getty Conservation Institute presented updates on their respective research and engaged in discussions. Representing TOBUNKEN, Dr. MIZUTANI Etsuko (Researcher, Preventive Conservation Section, Center for Conservation Science) and Assoc. Prof. IBA Chiemi (Graduate School of Engineering, Kyoto University; Visiting Researcher of TOBUNKEN) delivered the presentations. Active discussions were held on topics such as Japan’s climatic conditions, the unique structural characteristics of cultural property materials, and measurement methods required for risk assessment of deterioration.
Following the discussions, we toured the research facilities and had the opportunity to interact with researchers from diverse disciplinary backgrounds. The Japanese case provides valuable insights into the challenges of managing conservation environments for cultural heritage in countries with humid temperate climates. This visit was a highly meaningful opportunity to re-examine environmental conservation research from an international perspective and to explore possible directions for future collaboration.
Workshop venue
This seminar was jointly held by the National Center for the Promotion of Cultural Properties and Tokyo National Research Institute for Cultural Properties with the aim of gaining a common understanding of the specialized survey and evaluation methods used for the conservation environment for cultural properties, as well as of the materials and tools used in improving storage environments or providing safe storage.
The 7th meeting, titled “Sustainable Environmental Management in Consideration of Global Warming” was held on March 1, 2024, in a conference room of the National Center for the Promotion of Cultural Properties. Dr. MIZUTANI Etsuko, a researcher with the Cultural Heritage Disaster Risk Management Center, joined in an international workshop, “Changing Climate Management Strategies Workshop” held in Melbourne, Australia, in August 2023. She shared the contents of the workshop, identified issues in this seminar, and held discussions. She talked about the outlook of the workshop, held in response to the global climate change crisis, which has increased the worldwide need to conserve and utilize cultural heritage in more sustainable ways. Lectures, practical training, and discussions were held on the issues and solutions to be implemented in museums around the world. In particular, in a lecture on the historical background of management of the conservation environment for cultural heritage, changes to the guidelines for the temperature and humidity of conservation environment were shown as essential for promoting sustainable management strategies in the future. At the same time, a lecture was held on risk assessment and monitoring methods for cultural heritage, and on the last day, there were reports and discussions about individual cases; thus, it was a very dense workshop.
While participating in the workshop, Dr. MIZUTANI presented the participants with an issue concerning the impact of global warming on the conservation environment, and raised the subject of management of the conservation environment, and how to proceed with management strategies in Japan. There were five curators in charge of conservation or experts in conservation science at the venue in person, and 12 such persons participated in the seminar online, and these participants posed various questions related to the fundamentals of the conservation environment.
This seminar was a good opportunity to learn about overseas trends in environmental management for the sustainable preservation of cultural properties, and to reconsider how to deal with global warming and management of the conservation environment in Japan.
Home page of HERIe website
Professor Łukasz Bratasz giving a lecture
Lecture by Dr. Michal Lukomski
Scene from the workshop
A workshop on “Sustainable Risk Management for Collection in Museum, Utilization of HERIe Digital Preventive Conservation Platform” was held jointly by the Department of Conservation of the Graduate School of Fine Arts at the Tokyo University of the Arts, the Cultural Heritage Disaster Risk Management Center, and Tokyo National Research Institute for Cultural Properties (TOBUNKEN), on December 17, 2023.
The HERIe Digital Preventive Conservation Platform (https://herie.pl/Home/Info) is designed to support the collaboration between museum curators and conservation professionals when assessing the conservation conditions and safety of collections for display. It is a decision-making support platform that provides a quantitative assessment of risks to collections. At the moment, it includes modules that address environmental degradation factors such as air pollutants, lighting, inappropriate temperature, and relative humidity, and modules that allow estimation of fire hazards. The platform is being developed by several institutions with financial support from the European Commission and the Getty Conservation Institute.
The purpose of this workshop was to give museum conservators and restoration professionals experience with the use of the data of their own museums on the platform. It was a very good opportunity to invite teachers from overseas who are among the developers of this platform to hear directly about its effectiveness and how to use it, and to try it out in a classroom. As an introduction, Prof. Łukasz Bratasz of the Polish Academy of Sciences introduced the platform and explained the concept and structure, and introduced the topic of pollutants and chemical degradation in museums and galleries. Next, Dr. Michał Łukomski of the Getty Conservation Institute talked about modelling mechanical damage and using the tool to assess museum climates. Prof. Boris Pretzel (Invited Professor of Conservation Science at Tokyo University of the Arts) introduced the topic of the light degradation tool and the presentations finished with Prof. Bratasz explaining the tool for fire risk assessment. Other tools, such as the showcase tool, were also introduced and demonstrated during the day, giving all delegates a good introduction of the kind of information each tool can provide.
Many of the participants commented that they had deepened their understanding of the platform, with remarks such as that they wanted to return to the museum and use it because they learned about a very useful tool, and that they wanted to use it to assess light damage when they brought their collection to the restoration studio.
Since this platform is provided free of charge, we hope that it will be widely used both by those who participated, and those who could not participate in the workshop.
Measuring the surface temperature of the rock
Measuring the moisture penetration status above the rock
Measuring the surface temperature of the honden
The Center for Conservation Science conducts investigations for the conservation environment of wooden architecture built in rock caves.
The Natadera Temple in Komatsu City, Ishikawa Prefecture is a temple of the fusion of the Indigenous Hakusan Faith (the faith for Mt. Hakusan), and Buddhism. Its wooden honden (main shrine), which is an Important Cultural Property, was reconstructed in 1642 in a rock cave created via natural erosion. In recent years, aseismic reinforcing works have been installed. Since then, moisture condensation has often occurred during spring to summer time, which is problematic because it causes wood decay. Therefore, it is desirable to reduce the frequency of moisture condensation to conserve the shrine and its decoration in good condition.
To tackle this, the Center is conducting an environmental investigation to identify the occurrence factors of moisture condensation and to determine the appropriate countermeasures to reduce them. Rainwater, outer air, and heat capacity (ability to store heat) of the rocks affect the environment inside the cave. Therefore, the temperature and humidity in the cave, moisture penetration into the rocks, and surface temperature of the rock and the honden are being measured. We plan to pursue our investigation by continuous measurements of environmental data and analysis.
Moisture condensation causes many problems at many masonry constructions and stone chambers of burial mounds. In recent years in particular, the rise of temperature and absolute humidity in the summer season increases the condensation occurrence risk. There is an urgent need to tackle the global environmental challenges. However, for now, we suggest the achievable countermeasures in everyday management.
Injecting nitrogen into the bag set in the display case
Extracting the air from the bag using a pump
The Center for Conservation Science investigates the conservation environments of museums. Recently, the Kanagawa Prefectural Museum of Cultural History requested us to investigate the air quality in their exhibition cases. They detected some organic acids, however, the emission source was not identified. The emission source was needed for taking appropriate counter-measures. Moreover, the ratio of acetic acid and formic acid is called for as the current measurement was taking them collectively as organic acids.
Therefore, the Preventive Conservation and the Analytical Science Sections decided to investigate the emission source by applying the air quality investigation methods developed by the Analytical Science Section. Five points including the floors of two wall display cases (big and small size), the display surface of a tabletop case, the display stand, and the back panel, were targeted. As shown in the photos, the targeted measurement points were covered with bags made of airtight film and the 4.5 kg lead rings were set to seal them. Then, after replacing the air inside the bags with nitrogen and leaving them for 24 hours, the air was extracted from the bags using a pump, dissolved in ultrapure water, and analyzed using ion chromatography. Consequently, we measured the amount of acetic acid and formic acid emissions. Simultaneously, we checked the sealing degree by the measurement of CO2 density change inside bags over time.
We have identified the density of acetic acid and formic acid at each measurement point and will leverage these outcomes for future air quality improvement.
Lecture on measures against biodeterioration
Lecture on scientific research on cultural properties
The abovementioned training was held from October 5th to October 15th, 2020. Although we have received many applications, the training was provided to 17 curators and others (or half the usual number) as a measure against the spread of COVID-19. Starting from last year, the training is implemented jointly with the National Center for the Promotion of Cultural Properties (CPCP). The CPCP took charge of the training sessions in the first week and Tokyo National Research Institute for Cultural Properties (TNRICP) in the second week. During the training, various control measures were thoroughly implemented to prevent the spread of infection: body temperature checking, sanitizing, and avoidance of the “3C’s.” Moreover, the participants wore gloves during hands-on training sessions. Furthermore, training materials were distributed to each trainee.
During the first week when the CPCP was in charge, participants learned the basics of the conservation environment through classroom lectures. In addition, reports were made on the instruction and advice regarding the “Virus Removal and Disinfection Work at Museums, etc.” addressed jointly by three organizations, namely the Agency for Cultural Affairs, CPCP, and TNRICP. During the second week, certain sections at the Center for Conservation Science provided separate half-day sessions and provided classroom lectures and practical workshops with a variety of topics such as the concept of conservation and restoration of cultural properties, the method of addressing on-site issues with the application of basic natural science knowledge, and other topics. Participants appreciated these sessions, commenting that they were informative and useful. On the last day of the training, Dr. KOUZUMA, Director of the Cultural Heritage Disaster Risk Management Center established in October 2020, was invited to give a lecture on the “Disaster Risk Management of Museums,” which turned out to be a valuable occasion to think about the role played by museums in protecting cultural properties from disasters.
We will keep working to provide better trainings to suit the needs of the time in 2021.
