Conservation Practices in Museums: For Researchers and Museum Professionals 4431569081, 9784431569084

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Nobuyuki Kamba

Conservation Practices in Museums For Researchers and Museum Professionals

Conservation Practices in Museums

Nobuyuki Kamba

Conservation Practices in Museums For Researchers and Museum Professionals

Nobuyuki Kamba Tokyo National Museum Tokyo, Japan

ISBN 978-4-431-56908-4 ISBN 978-4-431-56910-7 (eBook) https://doi.org/10.1007/978-4-431-56910-7 Translation from the Japanese language edition: Hakubutsukan Shiryo no Rinsho Hozon Gaku by Nobuyuki Kamba, © Nobuyuki Kamba 2014. Published by Musashino Art University Press. All Rights Reserved. © Springer Japan KK, part of Springer Nature 2022 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, expressed or implied, with respect to the material contained herein or for any errors or omissions that may have been made. The publisher remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. This Springer imprint is published by the registered company Springer Japan KK part of Springer Nature. The registered company address is: Shiroyama Trust Tower, 4-3-1 Toranomon, Minato-ku, Tokyo 1056005, Japan

Preface

Of the many years of my experience in the conservation of cultural heritages, over the last 20 years, I have noticed the high effectiveness of integrated practice of diagnosis, preventive conservation, and remedial conservation of cultural heritage. The effect, of course, is that a higher level of stability and security is achieved for objects and the environment when exhibiting and storing of cultural properties. The appropriate balance of diagnosis, preventive conservation, and remedial conservation is important from the perspective of conservation of the object against the environment surrounding the object such as temperature and relative humidity, the human environment of curators and visitors, and the physical stability of the object. By approaching the object, the environment, and also the staff in such a way, the object can be stabilized or treated, and can be exhibited and stored in a low-risk state. Previously, I have conducted scientific research on conservation individually, such as research on objects, research on the relationship between the environment and deterioration of objects, and development and improvement of conservation processes. I started my conservation activities, from an integrated perspective as it is now, about 20 years ago when I started working at the Tokyo National Museum. About 20 years ago, the Tokyo National Museum was a facility that not only had a huge number of objects handled, such as loaning, renting, replacements, and remedial treatments, but also had many storage rooms and exhibition rooms that required environmental improvements. The challenges faced by the museums were so diverse and complex that they had no idea where to start. Therefore, it was necessary to create new approaches that could deal with these complex and diverse issues. In order to provide clear guidelines comprehensively for complicated intertwined issues and situations in which clues to solutions are not visible, individual methodologies were integrated and applied to the museum as one package. Clinical conservation has been created as a result of such conservation activities. In clinical conservation, deterioration is considered to be caused by the interaction of people, objects, and the environment, and the main theme is how to control the relationship of these three factors. Therefore, the person in charge of conserving the object must consider not only the object, but also the environment and people surrounding the object. In other words, it is important to approach people, objects, and the environment, and it is v

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necessary to keep in mind that the situation will greatly change depending on the approach. This book describes the conservation of cultural properties according to the concept of clinical conservation with this background. In recent years, the onehealth approach has been attracting attention as a countermeasure against infectious diseases. The one-health approach is a term that expresses the concept that stakeholders work together to solve cross-cutting issues related to human, animal, and environmental hygiene. It has a similar direction to the content of this book. It is becoming more and more recognized internationally. At 14:46 on March 11, 2011, a massive 9.0 magnitude earthquake occurred on the sea floor about 24 km off Sanriku coast. In Japan’s own seismic intensity class determined by the Japan Meteorological Agency, a maximum seismic intensity of 7 was observed in Kurihara City, Miyagi prefecture, and the epicenter extended approximately 100,000 square kilometers from offshore Iwate to offshore Ibaraki, about 500 km north-south and about 200 km east-west. The quake caused a massive tsunami with a maximum run-up of 40.1m in some places, causing catastrophic damage to the Pacific coast of the Tohoku and Kanto regions. The author has been supporting the conservation of damaged objects at the Rikuzentakata City Museum in Iwate prefecture since the earthquake, but his activities are based on the practice of clinical conservation developed at the Tokyo National Museum during normal times. First of all, the priority was given to understanding the condition of objects contaminated with salt, sludge, mold, and various bacteria due to the tsunami, and the environmental conditions of the closed elementary school where the objects were carried and where there was no footsteps. Next, various measures were taken to stabilize the objects and to improve the environment for conservation, thereby the deterioration of the objects is suppressed. These activities are still ongoing today. Damaged objects that have undergone the initial stage of treatment will be gradually performed full-scale remedial treatment in the future. In this way, this experience has verified that the methodology of normal times can be useful even in crisis situations, and we are now reaffirming its effectiveness. The Conservation Department of the Tokyo National Museum is a group of experts from the field of conservation, arts, and history, who have worked together to solve problems. In addition, clinical conservation has gradually grown and developed by improving the accuracy of practical skills while verifying the results obtained. I hope that this book translated with some changes in the order and contents of the Japanese version, which summarizes the methodology developed in this way, will be useful not only to those who aim to practice clinical conservation, but also to those who work at museums and those who are interested in cultural heritages. Tokyo, Japan

Nobuyuki Kamba

Conservation Practices in Museum with Integration of Diagnosis, Prevention and Treatment

Fig. 1 Removal of facing papers affixed for protection during treatment of a hanging scroll

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Conservation Practices in Museum …

Fig. 2 During dismantling of a folding screen

Fig. 3 Investigation of folding screen structure using terahertz spectroscopic analysis

Conservation Practices in Museum …

Fig. 4 Rejoined side arms of a wooden Buddha statue with Japanese lacquer mixed with flour

Fig. 5 Examination of a mummy using X-ray radiography

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Contents

1 Significance of Conservation of Cultural Heritages in Museums . . . . 1.1 Cultural Heritages and Museums . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1.1 Types of Cultural Heritages . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1.2 Museum Facilities that Preserve and Exhibit Objects . . . . . . 1.1.3 History of a Political System of Preservation of Cultural Heritages in Japan . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1.4 Conservation of Original Section . . . . . . . . . . . . . . . . . . . . . . . 1.1.5 Traditional Technology and Science . . . . . . . . . . . . . . . . . . . . 1.1.6 Organizations that Bring Museum Objects to Life . . . . . . . . . 1.2 What Are the Risks to Conservation? . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2.1 Risks Existing in Museums . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2.2 Causes of Damage to Objects . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3 The Reasons for the Need of Clinical Conservation . . . . . . . . . . . . . . 1.3.1 Planned and Systematic Implementation of Conservation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3.2 The Basic Three Elements for Conservation . . . . . . . . . . . . . . 1.3.3 Priorities in Conservation Activities . . . . . . . . . . . . . . . . . . . . 1.3.4 Costs in Conservation Activities . . . . . . . . . . . . . . . . . . . . . . . . 1.3.5 Practice of Clinical Conservation . . . . . . . . . . . . . . . . . . . . . . . 1.4 A Code of Professional Ethics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4.1 ICOM Code of Ethics for Museum . . . . . . . . . . . . . . . . . . . . . 1.4.2 Code of Professional Ethics for the Japan Society for the Conservation of Cultural Property . . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Diagnosis of Museum Environment and Collections . . . . . . . . . . . . . . . 2.1 Relationship Between Preservation and Environment . . . . . . . . . . . . 2.1.1 Risk Concentration and Preventive Measures . . . . . . . . . . . . . 2.1.2 Causes of Degradation and Period up to the Degradation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 Monitoring and Evaluation of Environment . . . . . . . . . . . . . . . . . . . .

1 1 1 2 2 4 5 6 7 7 8 10 10 11 13 14 15 16 16 18 20 21 21 21 22 29

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2.2.1 Clarify the Target of Monitoring . . . . . . . . . . . . . . . . . . . . . . . 2.2.2 Necessary Guideline for Optimization . . . . . . . . . . . . . . . . . . . 2.3 Diagnosis of Objects and Recording of It . . . . . . . . . . . . . . . . . . . . . . 2.3.1 Examination of the Condition of Objects . . . . . . . . . . . . . . . . 2.3.2 Diagnosis of the Condition of Objects . . . . . . . . . . . . . . . . . . . 2.3.3 Recording to Conservation Charts . . . . . . . . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

29 36 44 44 46 50 60

3 Environment and Preventive Conservation . . . . . . . . . . . . . . . . . . . . . . . 3.1 Improving the Environment and Preserving Objects . . . . . . . . . . . . . 3.1.1 The Significance of Control of Environment . . . . . . . . . . . . . 3.1.2 Preventive Conservation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1.3 Applying Risk Management . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1.4 Case Example at Exhibitions . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1.5 Case Example at Store House . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2 Safe Transport of Museum Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.1 Fundamental Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.2 Case Example of Transport of a Large Buddha Statue . . . . . 3.3 Preparation of a Safe Environment by Storage Box . . . . . . . . . . . . . . 3.3.1 Stabilizing Temperature and Humidity . . . . . . . . . . . . . . . . . . 3.3.2 Protection from Scratches, Soiling, and Impact . . . . . . . . . . . 3.3.3 Caution for Component . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

63 63 63 64 65 66 72 81 81 86 90 90 94 95 97

4 Deterioration and Remedial Conservation . . . . . . . . . . . . . . . . . . . . . . . . 4.1 Preliminary Examination for Treatment . . . . . . . . . . . . . . . . . . . . . . . . 4.1.1 Diagnosis and Recording of Condition of Objects . . . . . . . . . 4.1.2 Conservation Charts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2 Roles of Preventive Treatment and Full-Scale Treatment . . . . . . . . . 4.2.1 Reasons for Deterioration with Age . . . . . . . . . . . . . . . . . . . . . 4.2.2 Preventive Treatment and Full-Scale Treatment . . . . . . . . . . . 4.3 Conservation Reports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.1 Reports by Conservators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.2 Reports by Owners and Persons Keeping Objects . . . . . . . . . 4.3.3 Digital Databases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.4 Recording of Moving Images . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4 Case Examples of Full-Scale Treatment . . . . . . . . . . . . . . . . . . . . . . . . 4.4.1 Archaeological Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4.2 Art Craft . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4.3 Sculpture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4.4 Painting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4.5 Ethnographical Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

101 101 101 104 105 105 107 112 112 113 114 114 114 114 120 129 136 143 147

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5 Environmental Protection and Role of Museums . . . . . . . . . . . . . . . . . . 5.1 Coexistence with a Decarbonized Society . . . . . . . . . . . . . . . . . . . . . . 5.1.1 Global Warming and Regulations . . . . . . . . . . . . . . . . . . . . . . . 5.1.2 Efforts and Challenges for Making Reductions . . . . . . . . . . . 5.2 Preparedness to Natural Disaster . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.1 Rescue Operation of Cultural Heritages . . . . . . . . . . . . . . . . . 5.2.2 Stabilization of Damaged Objects by Seawater . . . . . . . . . . . 5.2.3 Crisis Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

149 149 149 154 157 157 166 167 171

6 Education and Disseminate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1 Disclosure of Conservation Activities . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.1 Showing Our Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.2 Showing to Visitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2 Conservation Education . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2.1 Training Specialists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2.2 Broadening the Importance of Conservation . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

173 173 173 174 178 178 181 182

Chapter 1

Significance of Conservation of Cultural Heritages in Museums

1.1 Cultural Heritages and Museums 1.1.1 Types of Cultural Heritages In the Act on Protection of Cultural Heritages established in 1950 is a fundamental system concerning protection of Japan’s cultural heritages. In Article 2 of the General Provisions of the Law for the Protection of Cultural Heritages, cultural heritages are categorized and defined into six fields of tangible cultural heritages, intangible cultural heritages, folk culture objects, monuments, cultural landscapes, and historic buildings. 1.

2. 3.

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Tangible Cultural Heritages: Tangible cultural objects, including building, pictures, carvings, folk crafts, writings, calligraphy and books, and old manuscripts upon which are placed high historical and artistic value. Tangible cultural heritages include land and other objects that form an integral part of these. Archaeological objects and historical objects of high scholastic value are also tangible cultural heritages. Intangible Cultural Heritages: Intangible cultural products of high historical and/or artistic value to Japan that include theater, music, and craft skills. Folk Cultural Heritages: Folk cultural heritages are those objects essential for understanding of transitions in the ways of living for Japanese that includes daily necessities, and also occupation and religious beliefs and annual events. And as well as clothing, implements, houses used in the above ways of living are included. Monuments: Cultural Heritages of high historical and/or artistic value for Japan include shell mounds, ancient tombs, site for forts, castle remains, old residences and other ruins. Historical sites of artistic and/or academic value that include gardens, bridges, ravines, beachfronts, mountains and others. Fauna are also categorized in this type of cultural object and include their habitats, breeding grounds, and migration. Flora, including natural habitats, and also geographical

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features and minerals belong to this category and include land providing unique natural phenomena, which are highly valued by Japan for their academic value. Cultural Scenery: Cultural heritages of scenic places formed by the climate of corresponding regions and the way of living and livelihoods of people in regions requiring understanding for the way of living and livelihoods of Japanese. Traditional Buildings: Traditional buildings that combine with the surrounding environment to form a historical essence and are of high value.

1.1.2 Museum Facilities that Preserve and Exhibit Objects Objects to be protected under the Act on Protection of Cultural Heritages are as previously stated, however, to these are added objects for preserving and exhibiting to the public by museum facilities and these include flora and fauna, minerals, fossils, meteorites among natural historic objects of academic value. This section shows a part of the Japanese Museum Act and introduces the definition of the Act that these objects are subject to preservation and exhibition. According to Act 1, this law is based on the spirit of the Social Education Law (1949 No. 207), which provides for necessary items concerning the establishment and administration of museums, and also promotes the social development of the museum with the purpose of contributing to the development of education, academics, and culture of Japanese citizens. In Act 2.3, “museum objects” means objects collected, stored, or exhibited by museums including electromagnetic records. And in Act 3.1 these are specifically real objects, specimens, reproductions, models, documents, Preamble s, photographs, films, records, etc. Act 3.4 and 3.5 mention that these museum objects shall be considered as a subject of research on history, preservation and exhibition.

1.1.3 History of a Political System of Preservation of Cultural Heritages in Japan Cultural heritages of Japan are those passed down until the early-modern times as private home treasures of the Imperial Household, noble families, and warrior families, treasures of temples and shrines, and the citizen. Until that time, a national political system for protecting and preserving such treasures did not exist. Leading into the Meiji Restoration in 1868, the new Meiji government issued the Ordinance Distinguishing Shintoism and Buddhism to establish Shintoism as a state religion. Buddhism lost its momentum rapidly due to the execution of the Edict, leading to ‘Haibutsu-kishaku’ means a movement to abolish Buddhism and the destruction of Buddhist facilities, statues, and objects in various places which with the assistance of rapid westernization after the Meiji restoration also came the sweeping in of the anti-Buddhism movement. The earliest ordinance concerning cultural heritages

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in Japan is the ‘Edict for the Preservation of Antiquities and Old Items,’ which was announced by the Meiji government in 1871. Items were classified into 31 categories, which later became the standard for cultural asset categorization. “Jinshin Kensa,” the first investigation on cultural heritages in Japan, was conducted from May through October of 1872 one year after the Edict. Based on this Edict, and a checklist of “Antiques and Old Items” was submitted to the government by temples and shrines mainly in the Kinki region. At that time, economic impoverishment of temples was extreme and multitudes of treasures were parted with by their owners to move out the extreme economic distress. The Horyuji-Temple, one of the most historical temple in Japan, donated a portion of their temple treasures to the Imperial Family Household, for which subsidies have been granted for temple’s building repair and also prevent the loss or disappearance of the rest of temple treasures. Donated items at that time have been preserved and exhibited as treasures of the Horyuji-Temple at the current Tokyo National Museum. Okakura Tenshin and Ernest Francisco Fenollosa, who at that time emphasized preservation of Japanese art, in 1888 in the Bureau of Provincial Inspection of National Treasures established in the Imperial Household Ministry, conducted an inspection with Ryuichi Kuki. That inspection focused on old temple and shrine treasures have been handed down from generation to generation that numbered approximately 215,000 pieces of object by 1897. In 1897, the “Law for The Preservation of Old Temples and Shrines” was established and the subsidy called “conservation fund” was released for conservation of applicable cultural heritages. In addition, the law objected for prohibiting the disposal and foreclosure of cultural heritages. Despite this system being only for temples and shrines, the law is significant as the first subsidy program in Japan. Entering the Showa Period (from 1925), due to extreme economic crisis and panic, private treasures collected by former daimyo who was warlords in Edo period were dispersed and lost. Furthermore, with pressing necessity to restore former daimyo’s castle structures which were left unattended for a long time, the conventional “Law for The Preservation of Old Temples and Shrines” was unable to meet keep pace with conservation requirements of general cultural heritages. Under such circumstances, in 1929, the “National Treasure Preservation Act” was then established to cover privately held cultural heritages. At the time of executing the law, 3704 treasures and 845 architectural structures were judged as national treasures. During the period until the newest “Law for the Protection of Cultural Heritages” was established in 1950, cultural heritages which were designated as national treasures were referred to as “old national treasures” later. During that period, in 1932, with the flowing out of the Kibidaijin Nitto Emaki, a picture scroll not yet designated as a national treasure and which is currently in the possession of the Boston Museum of Fine Arts, such grave circumstances resulted in the establishment of the “the Law of the preservation of important fine arts” in April of 1933 with the aim to prevent valuable art objects from going abroad that were not designated as national treasures. Shortly after the end of the Second World War, on January 26, 1949, the Horyuji Temple’s wall paintings were lost due to a fire in the Horyuji Kond, which is the main hall of the Temple. This situation presented government lawmakers with the

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opportunity in May of 1950 to establish the “Law for the Protection of Cultural Heritages” that was commenced in that same year in August. The “Law for the Protection of Cultural Heritages” is a comprehensive law pertaining to the cultural heritages, and by utilizing a two-tier designation system for national treasures and important cultural heritages. The enforcement of the law allowed delicate control in formulating protective measures. Currently, cultural heritages preservation measures are still executed based on the “Law for the Protection of Cultural Heritages”, which has gone through revisions repeatedly. On April 1, 2019, 1,116 national treasures were designated and 13,232 important cultural heritages were designated. In 1947, the Imperial Museum was transferred to be under the control of the Ministry of Education and it started as National Museum. The “Conservation Section” was created in the new museum, where surveying, designation, and also conservation of national treasures and other objects took place. In 1950, the “Cultural Heritages Protection Committee” was created as an external bureau of the Ministry of Education, to which administration of cultural heritage protection was transferred from the museum. Then in 1954, with the Tokyo National Research Institute for Cultural Heritages becoming independent of Art Research Institute of the National Museum, surveying and research pertaining to conservation of cultural heritage were separated from the National Museum. Following simplification of administrative organizations, in 1968, when the Cultural Heritage Protection Committee and the Culture Bureau of Ministry of Education merged to form the Agency for Cultural Affairs, the National Museum and the Research Institute for Cultural Heritages became attached organizations of the Agency for Cultural Affairs; however, in 1984, these were then further changed to an auxiliary organization. In 2001, the three museums comprising the Tokyo National Museum, Kyoto National Museum, and Nara National Museum merged to become the “Independent Administrative Institution National Museum”、after which in 2005, Kyushu National Museum was opened and also became part of this institution. In 2007, the “Independent Administrative Institution National Museum” and the Research Institute of Tokyo and the Research Institute of Nara that are part of the “Independent Administrative Institution National Research Institute for Cultural heritages” merged to become the present National Institutes for Cultural Heritage. The “International Research Centre for Intangible Cultural Heritage in the Asia–Pacific Region (IRCI)” was established in 2011 as a Category 2 Centre under the auspices of UNESCO and as one of the institutions of the National Institutes for Cultural Heritage. In 2019, the National Science Museum has joined the “Independent Administrative Institution National Museum”.

1.1.4 Conservation of Original Section The area in an as-manufactured condition of cultural heritages is termed “original”. Curative treatment or restoration is done to return cultural heritages to a stable condition and stop progress of deterioration arising from display of them for long years. As cultural heritages continue to receive restoration, such treatment results in those

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objects being preserved until the present. The repeated treatment increases physical stability of objects and allows for ease of handling objects although the original information and materials of the objects may not necessarily be preserved. On the other hand limitations then do also exist if objects are simply housed in a storage to preserve. The environment of temperature and relative humidity surrounding objects normally varies without being stable and absolutely set. In addition, large environmental changes cause mold and insect growth, a dimensional change in shape or destruction and it may lead to fatal deterioration. Therefore, the effect of storage will be produced only by understanding the appropriate environmental conditions for objects. Deterioration causing during display or storage are usually receive treatment such as restoration to recover the stable condition, and the same process is repeated for generations resulting original sections are affected gradually. Application such as display, preservation such as storage, and treatment such as restoration are closely connected to the conservation of cultural heritages, and erring in any of these three may result in significant impact on objects. In comparison with restorations provided for significantly damaged objects, the ratio of remaining original sections increases considerably with the treatment provided for slight deterioration that has steadily progressed by appropriately storage. The more severe the handling and the environment during the exhibition, the more demands are placed on restorations of objects to withstand them. Thus, the need decreases for treatment of objects being housed and exhibited under appropriate condition. Conservation of cultural heritages without requiring excessive reinforcement leads to preservation of the objects in their original condition.

1.1.5 Traditional Technology and Science East Asian objects of arts such as a painting and a calligraphy seen at museums and art galleries are exhibited in the form of hand scrolls, hanging scrolls, and/or folding screens. Maintaining of objects in such forms is possible owing to the traditional techniques of the “scroll mounting”. The scroll mounting is not only a skill for manufacturing new folding screens and hanging scrolls but also the skill required for conservation treatment. In addition, the full-scale restoration conducted about once every half century to wooden architectural structures that include temples, shrines, and castles are done by temple carpenters possessing special skill, which is supported by traditional techniques. Term of 10 years is said to be need at least to master these traditional techniques and skills, and even at the present, many young artisans and crafts people work on training to become specialists. It is no exaggeration to say that many of the cultural heritages we see today have been preserved by these traditional techniques. Additionally, we have learned from many years of experience from ancient, as an empirical rule, that housing of precious objects in paulownia wooden boxes and traditional wooden and clay storehouses maintains such objects in excellent condition for long periods, and we can really see the cultural heritages which

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have been preserved under such environments. Traditional materials and technologies are not only historical methods that have been inherited from the past, but also methods whose stability and usefulness have been evaluated over many years. Experience and intuitiveness, as well as various traditional materials have preserved cultural heritages; however, only these matters do not necessarily assure objects to remain in original condition. Under such circumstances, in addition to the above contributing factors, scientific views and approaches and also skills and materials should have been introduced with the current aim for truly assuring conservation. Combining tradition, whose stability has been confirmed over a long period of time, and the scientific methods with a variety of possibilities, will ensure the preservation of heritages if both perform their respective roles appropriately.

1.1.6 Organizations that Bring Museum Objects to Life Activities of museums are classified broadly into displaying objects of arts for the public and housing objects for preservation. Various aims of displaying objects of art to the public include exhibition of the collection and special exhibitions; accounting management of the objects on loan and for lent for exhibitions; transporting objects for the exhibitions; acquisition of objects by purchase or donation; and academic study of objects. The aims of conservation activities include housing the objects; conservation treatment to damaged objects, and environmental control of a storage and display areas, scientific investigations of objects. Such activities are not done separately, but are predominately done in combination (Ambrose & Paine, 2018). An exhibition will be given next as an example. In order to exhibit objects of art, first a list of the objects to be exhibited is constructed, and depending on the exhibition content, objects of other museums may arise as candidates. Whether a conservation condition of objects are in allowing such objects to be displayed will be confirmed, and whether the exposition period is appropriate for the objects must be judged. In cases that conservation condition is absolutely insufficient, it is necessary to consider whether displaying the objects can be performed by conservation treatment in a limited period of time. In the case of objects on loan, considerations are made for the methods of packing and transport, and whether fumigation treatment is required to prevent insects and mold from infecting the museum. In addition, in case of the object is transported after it has been received conservation treatment, the timing for the treatment must also be determined. Once the list of exhibits has been finalized, it is necessary to prepare an exhibition environment suitable for the content and condition of the objects. There are many points to consider, including the use of display cases, the use of seismic isolation devices to prevent tipping, the use of ramps for easy viewing, fixtures such as metal supports and fishing gut, the selection of rugs to be pulled under the objects, and lighting etc. All materials used in the fabrication of temporary exhibition cases and walls must receive prior inspection in order to investigate whether harmful gas is emitted that negatively impacts the conservation

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of objects. It is necessary to stabilize relative humidity and organic gases at target values in the exhibition area and within display cases prior to displaying of objects. For objects on loan from other museums, objects are packed in a crate and transported after checking of their condition. Upon arriving at the museum, one shall open shipping crates and inspect their condition after seasoning or fumigating if necessary. Objects requiring some form of treatment shall be done before packing or after opening the crate. Treatment of objects on display are usually small-scale or minimum one, and full-scale treatment is extremely rare. Various examples exist involving minimum treatments to prevent chipping of paint layers on polychrome Buddha statues and also gluing a weaker joint section of the main body. In the case of paintings, examples exist for replacement of such as damaged hanging strings for hanging scrolls and also affixing either peeled paper or silk. Required minimum treatments must be taken within the short permissible time by using appropriate materials and techniques which not interfere the future full-scale treatment. Upon completing a confirmation of the environment of the exhibition area and confirmation of the condition of the objects, the objects are finally carried into the exhibition space and positioned in prepared cases and on exhibition stages. Once positioning of the objects is completed, while adjusting lighting angles and the degree of the diffusion, the illuminance level suitable to the materials of the objects and their condition are decided. Exhibition area is checked every day to recognize presence/absence of abnormality with respect to the objects and the environment during the exhibition. In addition, in the event the objects are exchanged to another objects during the period of the exhibition, there are cases in which objects are returned to their original museums and borrowed other objects. In this manner it is understood at a merely glance in regard to an exhibition that display is made possible with the cooperation of myriad fields including aspects of art and history, collection management, conservation, and design (de Guichen & Kabaoglu, 1985).

1.2 What Are the Risks to Conservation? 1.2.1 Risks Existing in Museums Cultural objects collected in museums are almost all created in differing regions and eras, and have been housed separately until the present. It is not thought that they deteriorate by the same cause at the same time under such circumstances. By housing such objects together in a museum, the possibility increases for aging and damage which simultaneously occur in storages and exhibition area. Being aware that such a risk fundamentally exists in museums is extremely important. In addition to this, all of the following activities also carry the risk of degrading cultural objects, such as displaying objects in an exhibition room; housing objects in a storage house; transporting objects on loan; conservation treatment of damaged objects; photographs and videos shoot; and a researcher directly handling of objects

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for his study. Museums of modern times, which require active exhibition, are required to take concrete measures against these risks, to prepare for accidents and to operate in a sophisticated manner to respond to social demands. Activities performed in a more open environment and activities performed under an environment that seeks to avoid risks seem to be incompatible activities in different directions. However, realizing a higher level of publicity and a less dangerous environment while satisfying both is the mission of museums, and it is truly museum activity itself. In order to fulfill this mission, several points must be achieved. First, possessing accurate acknowledgement for the historical aspects and also physical conditions of objects while also acknowledging correctly the condition of the environment surrounding these objects are important. And following selection of an appropriate countermeasure and achieving solutions from a long-term viewpoint. There are various risks in museums. It is difficult to eliminate them completely, but it is possible to reduce the risks step by step and to preserve the cultural properties for a long time.

1.2.2 Causes of Damage to Objects The cause of damage to cultural objects is categorized into three groups by length of time until deterioration occurs—long-term effects from 10 to 100 years; midterm effects from one year to 10 years; and a short period less than one year or instantaneous effects. These three groups are explained in detail in a latter chapter, but a simple explanation is presented below. Damage resulting from long-term effects is deterioration of objects with the cause being continuing over a period of time from 10 to 100 years (Fig. 1.1). Abrasion is the concrete cause of hanging scrolls and hand scrolls due to repeated exhibition, changes in humidity, a high-humidity of storage environment, and repeated exposure of lights in exhibitions. Due to the progress of deterioration being so slow, the rate of damage progression is not able to perceive in many cases. In addition, the impact from repeated restoration to original sections progress slowly, but this is also included long-term effects. Damage resulting from mid-term effects is deterioration of objects with the cause is sustained for a period from one year to 10 years (Fig. 1.2). Indoor air contamination from such as formaldehyde and/or acetic acid gas emitted from construction materials inside buildings; intrusion of air pollutants such as nitrogen oxide and sulfur oxide from outdoors; and also biological damage due to mold and/or insects originating from outside and inside the museum are corresponding causes of mid-term effects. In addition, other causes include discoloration, hardening, and deformation of such as synthetic resins for which stability is not confirmed as conservation and restoration materials. The cause for damage resulting from short-term effects are shock and vibration during transport resulting from peeling and/or chipping of objects, the impact brought about by disasters such as earthquakes, fires, and/or flooding (Fig. 1.3). Myriad examples of accidents in which ceramics fell down that were on the storage shelf

1.2 What Are the Risks to Conservation?

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Fig. 1.1 Damage resulting from long-term effects. Powdering of ancient dyed textiles of the 7–8th centuries due to deterioration over time

Fig. 1.2 Damage resulting from mid-term effects. Damage to picture scrolls caused by insect pests

and on exhibition stand at the time of an earthquake. In rectifying such regrets, recently methods have been adopted for safely displaying of ceramics by placing them on seismic isolator.

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Fig. 1.3 Damage resulting from short-term effects. Overturning and damage of ceramics due to the Great Kanto Earthquake that occurred in 1923

1.3 The Reasons for the Need of Clinical Conservation 1.3.1 Planned and Systematic Implementation of Conservation Prior to being collected in a museum, cultural objects under the management of separate owners are preserved and managed together in a lot after the objects become to a part of the museum collection. Under the object owned separately and the management is dispersed, a multiple simultaneous deterioration of these objects is thought to be highly unlikely. However, because museums intend to collect objects under individual management previously, there exists the risk of deterioration and/or damaging to those objects for artificial reasons. In other words, if no measures are taken in museums, the risk increasing of deterioration by collecting objects must be taken as a premise. If the environment of a display and a storage areas of objects is inappropriate, deterioration to objects may be further accelerated. Also, excessive restoration treatment to prevent further deterioration tend to be applied to the objects even more. This situation goes against the initial purpose of preserving original part of objects. In the case of collected objects in museums being separately managed depending on the classification and value of the objects, lack of understanding of the entire collection makes it difficult to identify problems to be improved and rank them. In

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many cases, opportunities for extreme high-quality measures of conservation are easily attained for highly valued objects: however, lesser valued objects are often only housed without sufficient care. Thus, a situation of extreme imbalance should be replaced with organizational management necessary for averaging and lowering risk. With these points in mind, awareness of the possibility that degradation may concurrently occur because of managing the collection under the same environment. Thus, organizational and planned conservation activities become essential.

1.3.2 The Basic Three Elements for Conservation 1.3.2.1

Condition Diagnosis of Objects and Environments

The monitoring of the condition of objects and environments, and then recording them by a method of charting is one of the most fundamental operations from the point of managing objects. Monitoring allows the content of methods to be proposed based on the condition of the objects and environments. Three potential situations may be considered as opportunities for monitoring and surveying the condition of objects. The first opportunity involves inspection at the time of loaning objects to other museums. Objects loaned from the Tokyo National Museum to other museums are more than 2000 objects annually and this serves as an effective opportunity. The second opportunity involves inspection prior to displaying objects. Annually, approximately 5000 objects are exhibited. The third opportunity involves prior inspection to be conducted for full-scale remedial treatment, of which from between 200 to 300 are inspected annually. All inspection results are recorded on conservation charts. Subsequently obtained data pertaining to the same objects shall then be sequentially recorded on the same chart. Concrete conditions of objects concerning degradations, the causes, time and date shall be recorded as well as person who records the chart. Inspection of the environment is done to discover abnormalities by regular monitoring, involving such as reading a thermo-hygrograph in a storage and exhibition room. Such regular monitoring also involves confirming concentrations of harmful gases, and also grasping the number of organisms and also inhabiting distribution of harmful insects and mold. When any abnormality is discovered, whether the abnormality is associated with a facility failure shall be investigated, which would then lead to improvement. For any environment exceeding appropriate scope for a long time, it is important to continue monitoring and make improvement efforts in order to lead to future fundamental solutions. Also, even if the values indicated are appropriate for the environment, continuous monitoring to discover abnormalities is essential.

1.3.2.2

Preventive Conservation

Nevertheless cultural heritages are kept in a museum which is a special facility, they do become degraded. Degradation of objects progresses despite it being extremely

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minor when objects are touched by hand at the time of displaying and mere lit up with lighting. Deterioration progresses slowly due to the impact of various environments. Wear is one impact from repeated contact in case of display and the delicate change of dimension of paper and wooden materials due to fluctuation of temperature and humidity. Another factor is chemical reactions resulting from light and atmospheric contamination, as well as biological deterioration due to harmful insects and mold. The aim of preventive conservation is to control the speed of deterioration of objects and reduce negative environmental impact by maintaining all environments to where objects are carried. Concretely, measures to assure stability and safety of objects are as follows: elimination of contaminated air such as that containing sulfur oxides, nitrogen oxides and aldehydes etc.; appropriate intensity of illumination based on the material and elimination of hazardous light rays such as ultraviolet and thermic radiation; and also extermination of organisms such as harmful insects and also molds causing biological deterioration; measures to reduce vibration and impact associated with transporting of objects; and disaster preparedness for either natural or human-made disasters such as earthquake and a fire. In order for preventive conservation to be carried out effectively, the on-site environment must be understood scientifically by monitoring, and then the data analyzed and evaluated. In addition, a countermanagement proposal and on-site feedback must be conducted. Museum-wide efforts to allow environmental maintenance would comprise close coordination between conservation scientists, conservation specialists of objects, facility-related personnel, curators, cleaner staffs and others. From there, it is imperative to formulate an action plan for preventive conservation, while ensuring that staff members always have an interest in that action. A detailed explanation concerning preventive conservation will be presented in Chap. 3.

1.3.2.3

Remedial Conservation

Remedial conservation involves symptomatic treatment, full-scale treatment, and emergency treatment, of which any are measures taken to maintain original sections of objects. The terms restoration and repair will be referred to hereinafter as remedial treatment. Until executing a major and serious treatment, which is called full-scale treatment, generally stabilization of objects with normally providing symptomatic treatment is achieved, and also an exhibition is restricted to control the progress of damage. Prevention of vital damage to objects is possible through meticulous symptomatic treatment; however, when it is no longer safe to handle safely with symptomatic treatment, full-scale treatment is done. In judging if objects are able to be displayed, an important requirement is whether the objects can be handled safely. Prompt treatments to prevent minor damage from aggravating can ensure the safe handling of objects and enable active exhibition. By attempting to stabilize all damage in the end by full-scale treatment, damage will spread and becomes to be more serious during the time until full-scale treatment will be done. Thus, providing symptomatic

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treatment as daily management is done with the necessity of slowing the progress of deterioration. Yet, in this event, the premise is selection of methods and materials that do not hinder full-scale treatment in the future. Full-scale treatment is applied to objects whose condition are worse beyond the scope of symptomatic treatment, these are methods requiring sufficient time and cost. Full-scale treatment requires thorough prior inspection of object condition, selection of materials and techniques based on inspection results, and accumulating all records during treatment. There are also cases in which careful management is essential for the content of treatment that significantly impact the aesthetic value of objects, and a consensus based on those people relevant for such management is required. Emergency treatment is a temporary measure that in many cases is done as a premise especially for full-scale treatment. A detailed explanation is presented in Chap. 4 for remedial conservation.

1.3.3 Priorities in Conservation Activities It is hard to think that exhibition of objects can be separated from conservation because extreme care to protect against the risk of degradation at every stage of all activities is required so that cooperation is achieved for the safety of objects. This is achieved by the presence of a conservation expert or a person in charge. Daily activities as the intent of conservation of objects is not limited to only special spaces such as the conservation studio and laboratory, but must be carried out in all places both inside and outside the museum. It’s a clinical task to watch and snuggle the object to preserve it anytime, anywhere. In order to continue exhibiting objects to the public and at conservation of objects simultaneously, appropriate length of work time and expenses shall be allotted for the three elements which were previously given of “diagnosis”, “preventive conservation”, and “remedial conservation”. Placing together these elements designing of conservation activities as a whole is essential, and appropriate allotment is not universal, but differs by facility. For diagnosis, prioritizing is essential in order to correctly acknowledge and evaluate current conditions both of objects and environments. In a facility where clinical task must be carried out such as a museum, preventive conservation is positioned to be the prioritized concern over remedial conservation, and it is important to improve the environment of all spaces to where objects are carried and housed (Fig. 1.4). Additionally, in order to prevent deterioration of objects from exhibiting, by carrying out symptomatic treatment that assures stabilization of damage at an early stage, stability and safety are bestowed upon the objects with opportunities made possible to exhibit them. Through symptomatic treatment, the delaying full-scale treatment is extremely effective from the viewpoint of preserving the objects in their original condition as much as possible while reducing degradation of objects from displaying. Objects that have reached the stage of receiving full-scale treatment must be done it at the appropriate time. The flow of activities to be carried is then diagnosis at first, preventive

Treatment

Shift from cure to care

Environment

Preventive Conservation

Fig. 1.4 Shift from a concept centered on remedial conservation to preventive conservation

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Remedial Conservation

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conservation secondly, and finally remedial conservation and ultimately preventive conservation must fulfill central roles.

1.3.4 Costs in Conservation Activities Necessary environmental control for conservation is a costly task while being essential one. While air conditioning operation is 24 h per day at some museum facilities, many museums run air conditioning only one third per day. In the case of air conditioning a large building for 24 h, the museum must be ready for the necessary, high cost. As a museum, while maintaining exhibition, maintaining a high-level conservation environment is the goal of all museum. However, in reality, due to financial limitations, many museum facilities cannot help running air conditioning for short periods. In one respect, museums face difficulties in dealing with the recent situation of society about global environment, which seeks a solution to the mutually opposed issue that is termed invigorating administration and control of the amount of energy consumed. With the high costs necessary for air condition and also control of the amount of energy consumed, both serve as factors not allowing movement to maintain an appropriate museum environment. In another respect, the cost of necessary remedial treatment increases higher for objects as deterioration and damage become more severe. Furthermore, the more pieces of objects in such condition much more expenses of treatment greatly increase. In making direct efforts to conservation of objects, with the actual possible executable funds being too few for necessary treatment, often improvement lags without any progress. In such cases, the will to sustain activities has the tendency to wear away. However, even in such circumstances, it is important to pursue constantly those things one by one that can put into practice. At the same time, data must be kept for use in the future. Within limited financial resources, appropriate fund allocation for achieving effective goals is possible only by appropriate understanding the conditions of the environment and objects.

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1.3.5 Practice of Clinical Conservation 1.3.5.1

Mission

The mission of those involved in conservation of cultural heritages are as provided in the following: “Maximizing conservation skills and ideas through practice of such as preventive conservation and remedial conservation. Conservation research and education must be promoted to the aim of improving the social environment for preservation of cultural heritages. Conservation of objects shall always be done with awareness of exhibiting objects to the public, and having exhibiting of objects always being aware of conservation. Conservation and exhibition of objects are the two necessary wheels for passing down objects to the future.” In giving concrete meaning to this mission, the fields relate to cultural object preservation such as conservation science, cultural heritage science, archaeometry, and museology etc. explain from myriad angles about the meaning and practice of conservation.

1.3.5.2

Clinical Conservation

In making the aforementioned mission the premise, next is the role of a conservator. “With the goal of cultural heritages accession to a next or further generations and exhibiting the objects to the public, in order to ensure safety for large amounts of cultural heritages in various forms of degradation, realistic management must be appropriate and swift”. Stated more concretely, this is putting into practice “remedial conservation” which ensures safety with providing treatment to deteriorated objects, and “preventive conservation” which ensures the safety of objects from environmental changes during transport, exhibitions, and housing. The former manages visible risks, whereas the latter manages invisible risks. By this concrete management, helping to stabilize the deterioration of objects, then the quality of museum operations switches to a safe level for the collection. In broadening and deepening coordination with the various operations of museums, conservation activities and museum operations are necessary to be inseparably linked for achieving improved safety in all aspects. Conservators in museums are always close to objects, monitor the condition of the objects and the environment, and ensure the safety and stability of objects. Here, clinical management that restated is “clinical conservation” is necessary (Kamba, 2007).

1.3.5.3

Primary Care

The word “conservation” is associated conservational aspects as a matter of course, which include diagnosis of objects and environment, environmental control in storages and exhibition rooms, and remedial treatment based on the condition of objects.

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However, awareness of the existence and value of objects are only able to be recognized through exhibition for visitors. This leads to a better understanding of the significance of conservation. When objects are displayed in exhibition rooms, therefore, it is necessary to control the condition of objects and an environment surrounding them to allow maximized value to be received by visitors of museum so as to not lose both the historical and aesthetic value of objects. In other words, as conservation and exhibition are strongly correlated, conservation is always to be carried out while having awareness of both. Clinical conservation is stands with the fundamental principle from the position of conservation and exhibition of objects. For this to be achieved, efforts based on principles of effective implementation of conservation measures in the early stage and reliable assurance of remedial conservation based on necessity. Such conservation based on this principle is called “primary care” with meaning which is viewed as a whole.

1.3.5.4

Reform of Awareness of Conservation

The number of professionals or personnel assigned to the field of conservation in one institution is by no means large. Regardless of how small compared to the number of collected objects, size of the exhibit space, and area of the space for housing, from the viewpoint of only one specialist or person responsible, the volume is enormous and the area expansive. Concrete activities begin with a long-term perspective at the onset of operations, but eventually, they realize that it is impossible for a small number of experts to grasp all the space and objects. It is necessary at that time to make up for the shortage of manpower by dividing the roles of staffs in other departments rather than limiting the target to just what you can do. In order to achieve this, along with having awareness that experts and staff will practice conservation jointly, and then educational considerations should be given to raising staff awareness of preservation and sharing their mission. The only way to ensure sustained preservation activities is to spread awareness of conservation across museum staff.

1.4 A Code of Professional Ethics 1.4.1 ICOM Code of Ethics for Museum ICOM, the International Council of Museums, is an international non-government organization founded in 1947 with approximately 30,000 museum specialists participating from 137 countries around the world. Within ICOM are comprised 119 National Committees organized by country, and 30 International Committees organized by various museum fields. Regularly annual meetings are held at which information exchange and knowledge is shared.

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ICOM Code of Ethics for Museum, revised in October of 2004, are the simplest standards designated for museums throughout the world, and are the fundamental principles for occupation practices designated for those objecting therein. By individual country, acceptance of such simple standards designated here may receive differently with certain countries regulated by laws and other without such laws. Museum professionals include curators, conservators and conservation scientists, but each fields are formed by Code of Professional Ethics. However, few countries have public qualification systems, such as for “architects” and “doctors”, for specialized conservators. Thus currently, with anyone able to handle precious objects, clarification is sought for furthering Professional Ethics. ICOM Code of Ethics for Museum comprise the below 8 items (ICOM 2017). 1.

MUSEUMS PRESERVE, INTERPRET AND PROMOTE THE NATURAL AND CULTURAL INHERITANCE OF HUMANITY

Principle: Museums are responsible for the tangible and intangible natural and cultural heritage. Governing bodies and those concerned with the strategic direction and oversight of museums have a primary responsibility to protect and promote this heritage as well as the human, physical and financial resources made available for that purpose. 2.

MUSEUMS THAT MAINTAIN COLLECTIONS HOLD THEM IN TRUST FOR THE BENEFIT OF SOCIETY AND ITS DEVELOPMENT

Principle: Museums have the duty to acquire, preserve and promote their collections as a contribution to safeguarding the natural, cultural and scientific heritage. Their collections are a significant public inheritance, have a special position in law and are protected by international legislation. Inherent in this public trust is the notion of stewardship that includes rightful ownership, permanence, documentation, accessibility and responsible disposal. 3.

MUSEUMS HOLD PRIMARY EVIDENCE AND FURTHERINFG KNOWLEDGE

FOR

ESTABLISHING

Principle: Museums have particular responsibilities to all for the care, accessibility and interpretation of primary evidence collected and held in their collections. 4.

MUSEUMS PROVIDE OPPTUNITIES FOR THE APPRECIATION, UNDERSTANDING AND MANAGEMENT OF THE NATURAL AND CULTURAL HERITAGE

Principle: Museums have an important duty to develop their educational role and attract wider audiences from the community, locality, or group they serve. Interaction with the constituent community and promotion of their heritage is an integral part of the educational role of the museum. 5.

MUSEUMS HOLD RESOURCES THAT PROVIDE OPPORTUNITIES FOR OTHER PUBLIC SERVICES AND BENEFITS

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Principle: Museums utilize a wide variety of specialisms, skills and physical resources that have a far broader application than in the museum. This may lead to shared resources or the provision of services as an extension of the museum’s activities. These should be organized in such a way that they do not compromise the museum’s stated mission. 6.

MUSEUMS OBJECT IN CLOSE COLLABORATION WITH THE COMMUNITIES FROM WHICH THEIR COLLECTIONS ORIGINATE AS WALL AS THOSE THEY SERVE

Principle: Museum collections reflect the cultural and natural heritage of the communities from which they have been derived. As such, they have a character beyond that of ordinary object, which may include strong affinities with national, regional, local, ethnic, religious or political identity. It is important therefore that museum policy is responsive to this situation. 7.

MUSEUMS OPERATE IN A LEGAL MANNER

Principle: Museums must conform fully to international, regional, national and local legislation and treaty obligations. In addition, the governing body should comply with any legally binding trusts or conditions relating to any aspect of the museum, its collections and operations. 8.

MUSEUMS OPERATE IN A PROFESSIONAL MANNER

Principle: Members of the museum profession should observe accepted standards and laws and uphold the dignity and honour of their profession. They should safeguard the public against illegal or unethical professional conduct. Every opportunity should be used to inform and educate the public about the aims, purposes, and aspirations of the profession to develop a better public understanding of the contributions of museums to society.

1.4.2 Code of Professional Ethics for the Japan Society for the Conservation of Cultural Property In Japan, with many conservators and scientists belonging to the Japan Society for the Conservation of Cultural Property, the “Code of Professional Ethics for People Involved in the Japan Society”, established on July 8, 2008, with worldly trends indicated on the previous page (The Japan Society for the Conservation of Cultural Property, 2008), and also “Code of Conduct for Scientists” provides for a strong sense of crisis for incorrect behavior of scientists as indicated by the Science Council of Japan (Science Council of Japan, 2013). The Code of Professional Ethics is introduced below. PREAMBLE

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Cultural heritages comprises tangible and intangible heritages of esthetic, historic, and academic values that have been created by both humans and nature. Heritage, shared and common inheritance of mankind, is not only used in our generation, but must be conserved for future generations. The Japan Society for the Conservation of Cultural Property thus has the aim to achieve expansion and spreading awareness of science and technology relating to preservation and utilization of cultural heritages. In order to achieve this aim, the Japan Society for the Conservation of Cultural Property members fulfill their responsibilities as specialists and also act with the selfdetermination to own responsibility for the public peace, the health of humankind, and also historical, cultural, and natural environments. Additionally, they dedicate their best efforts to expanding this field to broaden understanding toward conservation of cultural heritages through education and spreading awareness. With this acknowledged, code of professional ethics of the Japan Society for the Conservation of Cultural Property is established here, and is the code that should be followed by its members. At the same time, it is believed that this will broadly become the professional ethics that should be followed by those involved with conservation. 1.

RESPECT FOR CULTURAL GERITAGES

The members of the Japan Society for the Conservation of Cultural Property, in recognizing cultural heritages are precious heritage of humankind and having respect to them, perform measures for surveying, research, exhibition, conservation, and restoration. 2.

RESPECT FOR THE VALUE OF CULTURAL HERITAGES

Members of the Japan Society for the Conservation of Cultural Property, in performing measures for surveying, research, exhibition, conservation, and restoration, they will consider and select correct methods and materials so as not to lose the esthetic, historical, and academic value of cultural heritages. 3.

ENSUREING SAFETY

Members the Japan Society for the Conservation of Cultural Property, in considering safety for the health and the environment, will select that which is appropriate among such methods and materials used in performing measures for surveying, research, exhibition, conservation, and restoration. 4.

EMPHASIS ON THE ENVIRONMENT FOR CULTURAL HERITAGES

Members of the Japan Society for the Conservation of Cultural Property, in recognizing that establishing an appropriate environment for long-term conservation of cultural heritages is most important, they should object to realize a better environment for cultural heritages. 5.

SELF-STUDY

Members of the Japan Society for the Conservation of Cultural Property make best efforts to fulfill maintaining and improving specialized knowledge, ability, and skill on their own through opportunities such as academic meeting, education, and research.

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COOPERATION WITH EXPERTS

Members of the Japan Society for the Conservation of Cultural Property will show self-determination in the conservation of cultural heritages that involves a multitude of fields, including esthetic, history, culture, and natural science. They will actively seek cooperation of other experts for measures in surveying, research, exhibition, conservation, and restoration. 7.

RELATIONSHIPS WITH OTHER EXPERTS

Members of the Japan Society for the Conservation of Cultural Property will be self-determined to be loyal and respectful in objecting with other experts and while concurrently judging correctly what other experts have achieved, they have to humbly listen to criticism of those experts. 8.

PREPARATION OF RECORD, KEEPING A RECORD, AND PUBLISHING

Members of the Japan Society for the Conservation of Cultural Property will create correct records and reports in continuing to secure trust for measures in surveying, research, conservation, and restoration, and also make efforts to make public announcements along with correct storage and management. 9.

OBSERVANCE OF ORDINANCE

Members of the Japan Society for the Conservation of Cultural Property shall observe ordinances and related rules pertaining to measures for surveying, research, exhibition, conservation, and restoration. In addition, they shall observe intellectual outcomes and intellectual object rights and not infringe upon them. 10.

OBSERVING A CODE OF ETHICSD

Members of the Japan Society for the Conservation of Cultural Property shall observe the code of ethics and encourage other members to observe them.

References Ambrose, T., & Paine, C. (2018). Museum basic. Routledge. de Guichen, G., & Kabaoglu, C. (1985) How to make a rotten show-case. Museum (UNESCO) (Vol. 146, pp. 64–67). International Council of Museum. (Ed.). (2017). ICOM code of ethics for museums. https://icom. museum/wp-content/uploads/2018/07/ICOM-code-En-web.pdf Kamba, N. (2007). Primary care and practice of conservation. Report on the International Symposium on Practice of Conservation in Museums—Present and Future, Tokyo National Museum, Tokyo, 6 June 2006. Science Council of Japan. (Ed.). (2013). Code of conduct for scientists. http://www.scj.go.jp/en/rep ort/Code_of_Conduct_for_Scientists-Revised_version.pdf The Japan Society for the Conservation of Cultural Property. (Ed.). (2008). Bunkazai no hozon ni tazusawaru hito no tameno kodokihan (Code of professional ethics for the Japan Society for the Conservation of Cultural Property). https://jsccp.or.jp/abstract/regulate_08.html

Chapter 2

Diagnosis of Museum Environment and Collections

2.1 Relationship Between Preservation and Environment 2.1.1 Risk Concentration and Preventive Measures Cultural objects are a valuable heritage in which knowledges and experiences developed by mankind are indwelled. There is no substitute for those. While being an index of looking back at the path walked for humans, this is at the same time the seed of creation, and that which is essential for building a prosperous future. Therefore, these cultural objects should be passed down in the future and used effectively at present generation. Additionally, museums continue to systematic research on the esthetic and historical value of cultural heritages, and it is necessary for museums to be the place of the core to realize preservation and exhibition of the objects. Prior to objects being added to museum collections, such objects were kept separately by individuals and families. If daily management of each object were to be done appropriately, possibility associated with damage occurrence to objects exist not in proximity of one another would be extremely low with concurrent damage being difficult to imagine. This circumstance is the condition of the risk dispersion. Whereas, when objects being managed together in the same environment as museum collections the possibility of concurrent damage occurrence increases, resulting in the risk concentration. Museums keep large volume of collection must recognize this latent risk with concentrating objects in one location, and active and planned efforts must be made for establishing a circumstance to preserve collections in the museum. Although there may be some cooperation to lower the risk until this time, such efforts may be said to have been excessively partial and individual. Because museums achieve their role as a place of the core for preserving and utilizing cultural heritages, it is necessary for the entirety of risk to be acknowledged and necessary for measures to reduce risk to be possessed on an organizational level.

© Springer Japan KK, part of Springer Nature 2022 N. Kamba, Conservation Practices in Museums, https://doi.org/10.1007/978-4-431-56910-7_2

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2.1.2 Causes of Degradation and Period up to the Degradation The cause leads objects to degradation is categorized according to the period required until a condition of degradation can be confirmed. Such period is divided into three categories—from 10 to 100 years, which is a period called “long-term effects”; from one year to 10 years, which is termed “mid-term effects”, and a period of less than one year, which is called “short-term or instantaneous effects”. An understanding of the differences among these three effects leads to appropriate management of objects.

2.1.2.1

Long-Term Effects

Aging, relative humidity, illuminance, utilization, and remedial treatment are included in this category. Deterioration and/or damage resulting from long-term effects occur when the effects last for an extended period of about 10–100 years. Over a long period, accumulated impact results in gradually progressive deterioration. Due to the change being so gradual, it is difficult for humans to recognize such degree of change. One cannot aware of the impact results until damage is clear in many cases. Such long-term effects are those for which humans are not good at perceiving. For the reason that cultural objects comprise physical matter, objects gradually deteriorate and the original form is lost by aging effect. This aging deterioration is a kind of natural disintegration, and there are also artificial causes that affect the promotion of deterioration. Clearly differentiating these two causes of deterioration is difficult. Therefore, it is challenging to determine the main cause in the process of deterioration up to this present, as well as clearly surmising changes thereafter. Concretely, changes in relative humidity, high temperatures and relative humidity, the degree of illumination of lighting in exhibition (Kamba, 1991a; Michalski, 1987), and wear resulting from repeated use of such as hanging scrolls and hand scrolls, among other factors lead to deterioration of objects by combined and long-term effects (Fig. 2.1). Changes in temperature and relative humidity which lead to fluctuations in water content of organic objects promote mechanical deterioration of objects through shrinkage and expansion of materials. High relative humidity and temperature promote chemical deterioration of materials. Photochemical reaction from illuminance results in weakening of fibers and fading such as a loss of color and yellowing. Light sources emitting ultraviolet radiations that possess chemical effectiveness bring about similar changes. Light sources emitting infra-red radiations cause objects to heat, resulting in changes to water content in objects which then leads to deformation. In addition, surrounding air temperature is increased, resulting in a loss of water content in objects. Such repeated shrinkage and expansion of objects leads to mechanical deterioration (Thomson, 1978; Toishi, 1970). Quantifying the amount of deterioration in objects over a short period of only one year is extremely difficult.

2.1 Relationship Between Preservation and Environment

23

Fig. 2.1 Creases and sprit cracks on the hanging scroll due to repeated exhibiting with repeated opening and rolling

In the process of remedial treatment/restoration repeated in every 100–200 years, which may include cleaning and lining etc., the original portions may be impacted by the treatment. However, for improving safety in handling of deteriorated objects, options other than remedial treatment/restoration are few. Many objects have survived to this day owing to remedial treatment, which is a fact and is greatly significant. With assurance, it can be said that even with methods of remedial treatment, complete

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2 Diagnosis of Museum Environment and Collections

Fig. 2.2 Ainu textile “Chukaukapu” garment deteriorated by the influence of iron mordant and repeated exhibiting

original sections cannot remain, and the act of remedial treatment will also come to have impact on original condition. The original materials of objects themselves can cause the progress of degradation of objects (Fig. 2.2). The degradation and breakdown of fibers seen in black-dyed textiles is thought to be impact on an iron mordant, which is used at the time of method for dying. In addition, on portions of paper on which a green mineral pigment such as malachite is used, paper turns brownish color with heavy deterioration. There is impact by original materials of either case with only remedial treatment as the way to achieve maintaining the current condition.

2.1.2.2

Mid-Term Effects

Biological degradation, atmospheric contaminating substances, and impact from materials for remedial treatment are involved in this category. Deterioration that appears from mid-term effects is the cause that is sustained spanning over a period from one to 10 years. Harmful insect breeding occurs when temperature/relative

2.1 Relationship Between Preservation and Environment

25

humidity levels and target food for insect pest within the museum match the conditions suitable for breeding. If such conditions repeat for some period of time in every year, a high probability of objects being threatened by mold or harmful insects exists, and material deterioration will progress (Fig. 2.3). Such a circumstance is termed biological degradation. Mold and harmful insects are able to be confirmed by the naked eye from the surface of objects themselves, so immediate insecticidal measure to the mold and insects is possible. However, the same problem can reoccur unless possible basic measures are taken, such as blocking the path of entry or transport, cleaning the inside of the museum, and maintaining the environment for temperature/relative humidity. When both airborne particulate substances such as dust and soot, and automobile exhaust gas contained in air outside the museum have passed through air conditioning systems into the museum, they are gradually collected in the storage and on the surfaces of objects resulting in contamination by such substances (Fig. 2.4). The airborne particulate substances in the air may potentially cause a chemical effect, which cannot be considered simply the accumulation of dust. Interior materials, such as construction materials and shelving brought in to the storage and exhibition room, may release harmful volatile gases. For example, if new cypress lumber that releases a large volume of its volatile oil and resin which is the extracted component of wood is used in a room, the substances released will attach and degrade the surfaces of

Fig. 2.3 White spotted mold on the surface of the wooden storage box due to high relative humidity

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2 Diagnosis of Museum Environment and Collections

Fig. 2.4 In the middle of cleaning the dirt of cloisonné ware in the Qing era of China

objects. Also, from boxes in which plywood boards and acidic paper are used that contain large volumes of such as formaldehyde and acetic acid, the objects will be effected chemically and deteriorate. This is impact from air pollution. Additionally, if synthetic resins, for which stability has not been confirmed, are used as remedial treatment materials, discoloration and deformation, etc. may occur after several years due to deterioration of components of synthetic resin. Objects deteriorate by materials of remedial treatment; for example, a layer of resin remains that changes to brownish color from colorless and transparent, and further shrinks with loosening of the paint layer. As a concrete example of damage that occurred from mistaking the selection of materials, there was the case of a lead weight imbedded in wooden shaft of a hanging scroll from a past era in order to pull the hung paper taut. The lead reacted slowly with the chemical content of the wood, causing the lead to rust. As a result, the beads of rust from the wooden shaft came out and made a hole in the paper or silk of object. By analyzing white rust, the lead had turned into basic lead carbonate. The chemical reaction of the lead is surmised to have required several decades (Fig. 2.5).

2.1.2.3

Short-Term and Instantaneous Effects

Natural disasters, transport, theft, and excavation are included. Deterioration appearing from short-term effects is damage caused by sustained spanning over only

2.1 Relationship Between Preservation and Environment

27

Fig. 2.5 Damaged shaft of hanging scroll due to corrosion of lead embedded in the shaft

a period of short time such as one year or less, and momentary shock, and includes damage from accidents. When objects are severely impacted by earthquakes, fires, flooding, a certain degree of damage must be expected. Although minimizing damage by daily drilling and preparation are effective measures, perfect preparation for unexpected disasters is challenging. In the Great Hanshin Awaji Earthquake in 1995 and the Great East Japan Earthquake in 2011, an enormous amount of cultural heritages were damaged instantaneously by tipping over and the tsunami. For objects damaged by the flooding and tsunami, after disaster, in cases of insufficient housing conditions for objects, secondary damage risks exist from short-term progress of rot due to mold and/or bacteria. Annually, the Tokyo National Museum loans more than 1000 pieces of the collection by requests from other museums (Actual 2018 fiscal year requests were 173 organizations for 1355 pieces requests). On one hand, the museum borrows several hundred works from other museums for holding a special exhibition. The Tokyo National Museum by itself has this much shipping amount, which on a world scale, a tremendous volume of works are transported. Damage to objects results in many cases during shipping and packing operations. Damage during shipping often occurs when carried by human hand, truck, and airport dolly, with dropping, vibration and shock of the packing case thought to be causes. Normally, in many cases clear effects from vibration and shock to objects are unable to be observed after transport; however,

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it must not be forgotten that actually there is some influences being accumulated. Particularly large objects and heavy objects require caution. For ceramic and clay objects assembled by fragments, those periphery of a joining place are characteristically fragile. A difference in the strength of the fragments and the adhesive or filler material are thought to be the cause (Fig. 2.6). A cause of damage in packing operations is scraping, dropping, and shock in the event of inserting and removing objects from a packing case. If upon arriving at the destination the packing case is opened prior to acclimatization for the environment, there is the possibility of peeling of color layers or deformation due to sudden changes in the environment. Recently, shipping by ship, which is now less prevalent, dew may form in the packing case when the case get stuffy if passing in the vicinity of the equator. The dew then forms mold. Severe damage may remain on works due to theft. During a heist, portions of objects may be damaged and intended damage may be afflicted, such as removal of sections. Also, original form may be lost for the purpose of selling an object. Such risk of damage leading to destruction of objects is extremely high. In order to prevent heists, establishing a security system is fundamental. As a special case example, an object unearthed by excavation making contact with the atmosphere concurrently deteriorates rapidly. In waterlogged wooden objects that contain several hundredths percent water, rapid shrinking and deformation occur

Fig. 2.6 Cracks in the legs of ancient clay figure caused by vibration and shock during transportation

2.1 Relationship Between Preservation and Environment

29

along with drying of the wood unless resin or sugar is injected and replaced with water. Unearthed metallic objects making contact with oxygen in the air concurrently reacts and corrosion progresses rapidly on the surface.

2.2 Monitoring and Evaluation of Environment 2.2.1 Clarify the Target of Monitoring Although there are myriad environmental factors relating to deterioration of objects, focusing to give attention to causes of particularly significant impact, while introducing suitable equipment to each, measurement of transition of these factors over a long period is called monitoring (Kamba Kamba, 1991b). Temperature and relative humidity, illuminance, atmospheric contaminating substances, organisms, and vibration for the three categories indicated in the previous “[2] Causes of Degradation and Period Up to the Degradation” are factors fundamentally monitored in museum facilities.

2.2.1.1

Temperature and Relative Humidity

In watching and recording temperature and relative humidity, (a) there is the method by which an air conditioning sensor connected to a central machine room controls for conditioning air inside the museum facility, (b) a method using a small temperature and relative humidity data logger installed in a necessary position and that regularly collects data by computer (Fig. 2.7), (c) recording thermo-hygrograph (2–8) is installed and read on site (Fig. 2.8). The above (a) is a sensor necessary for controlling air conditions, and (b) is used for grasping the environment in extreme detail. Both (a) and (b) data are often used for analysis because they are easy to process on a computer. The above (c) is often used on site to confirm values at that time by direct reading. Also, (c) is often installed for the purpose of comparing the confirming of (a) and (b) accuracy. The data of (a) accumulated in the computer memory in the central machine room is collected once a month and filed. Data accumulated in the small data logger (b) is also read and saved on the computer on fundamentally a monthly basis. Types of small data loggers allow sending and receiving of data by wireless communication, and in matching this to the museum LAN, data can be read in real time from a remote location. An exchange of the recording sheet once per month occurs for data (c) of the recording thermos-hygrograph, and the collected recording sheet is filed and saved. Collected raw data is then soon passed around related departments in the museum and deeper understanding is desirable by sharing of the current situation as a whole. In the case of an abnormality, the confirmed date and time, location are taken as a memo, and the cause of the abnormality is validated together with the related

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2 Diagnosis of Museum Environment and Collections

Fig. 2.7 Temperature and humidity data logger installed in display cases

Fig. 2.8 Hair-type self-recording hygrothermograph

2.2 Monitoring and Evaluation of Environment

31

department. In order to understand the transition of data of (a) and (b) over one year, temperature and relative humidity data of the entire museum is organized for each measurement point. And for whether the temperature and relative humidity conditions are appropriate, a hazard map (degree of risk information map) is created that divides the museum interior by color, which achieves awareness for progressing in understanding current conditions. By reading transitions in daily temperature and relative humidity fluctuations, action is often sought based on necessity. Air conditioning abnormalities are searched for by comparing with data from the previous fiscal year and/or averages, on which is based and improvements. Other than this, on a daily basis, air conditioning operations are performed while observing data. Such operations include settings and control of temperature and relative humidity when holding special exhibitions, setting up portable humidifiers and de-humidifiers during low humidity times of the year in the winter and high humidity months during the summer, countermeasures for condensation that forms on walls, and humidity control within exhibit cases. In the mid-to long-term, the order of priorities are presented against locations that should be improved based on collected data and clarifying environments.

2.2.1.2

Radiation from Light Sources

The strength of visible radiation for irradiating light is measured in illuminance (unit: lx), and total dose of light exposure on objects is product of illuminance and exposure time (unit: lx h). When designing display lighting, performance of equipment and lamps are considered from the point of protecting objects. In particular, considerations are given to quality of light spectrum, which includes whether there are ultra-violet rays or infrared rays, the degree of color rendering, and color temperature. In terms of lighting, while continuous measurement is important, but due to the importance of initial condition settings, measurement of illuminance is usually done only immediately after the display work, not continuously (Fig. 2.9). While continuous monitoring is possible by a data logger that records the strength of illuminance, because the illuminance values can be shown to be stable at almost being fixed, after completing exhibition operations, the goal can be achieved by ensuring measurement of the initial value. Other than this, in order to provide a highly-visible and safe environment for museum visitors, use of the high transparency ratio glass and/or low reflection film on the glass of the display case are also to be considered. Due to an easy to view museum objects leading to keeping illuminance at low level, this is effective for conservation of objects.

2.2.1.3

Atmospheric Contaminating Substances

Contamination of cultural objects from airborne contaminated substances are not only in outdoor sculptures and architectural structures, but also in museum objects

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Fig. 2.9 Measurement and adjustment of illuminance level after displaying objects

that displayed and housed. Rot and erosion resulting from exposure to acid rain outdoors, and also indoor air contaminants from harmful substances emitting from the structural skeleton, interior materials, storage containers within the museum, and air pollutants in outdoor invaded through air conditioning equipment are thought to be atmospheric contamination. Atmospheric air pollutants that flow into the museum and affect objects is airborne dust, such as sand and also particulate matter, photochemical oxidants, nitrogen oxides (NOx), and sulfur oxide (SOx). In addition, chloride ions contained in seawater carried from the sea have a great effect. Indoor air contaminants include formaldehyde, acetaldehyde, acetic acid, formic acid, and other volatile organic compounds (VOC) released from adhesives in plywood and interior materials of wall cloth coverings and paint, and also ammonia released from concrete skeletal structures (Tsujino et al., 2002). Normally, the above mentioned substances are repeatedly measured and those substances with high concentrations and also their sources are specified by the measurement. When the source of such contaminants is determined, concentration is reduced through taking measures such as fitting and changing filters and installing absorbents to air conditioning system, and/or increasing the number of times of ventilation. A solid and fundamental solution requires elimination of the source, however, removal and replacement of interior materials and shelving is often not possible, thus requiring preventive measures to be taken. An assured way to decrease the occurrence of indoor air contaminants is thorough material inspection prior to installation. Measuring of contaminants can be done either by active sampling involving analysis of air collected by using a pump, and also passive sampling, which involves analysis of a chemical agent sampler which is installed for several weeks (Fig. 2.10).

2.2 Monitoring and Evaluation of Environment

33

Fig. 2.10 Measurement of concentration of atmospheric contaminating substances by passive sampling method

Active sampling involves an instantaneous value, and passive sampling seeks an average value for a certain period. Active sampling is utilized immediately after completion of construction of a facility, and passive sampling is appropriate for continuous measuring at normal period. In addition, an Oddy Test, for reference, is safe testing method for materials being used. The Oddy test involves a method for assessing impact from materials being investigating on metal fragments (Bamberger et al., 1999). Photographic Activity Test (PAT) is also a method for assessing materials which is normalized by International Organization for Standardization as ISO 18916.

2.2.1.4

Pests

Infection by mold and also vermin damage caused by harmful insect causes irreversible damage to objects (Tables 2.1 and 2.2). Harmful insects invades from minimal opening of doors and/or invades by attaching to and being carried in by museum visitors, there are cases in which such harmful insects attach to objects that are then transported. Museum interior temperature and relative humidity, volume of accumulated dust that includes nutritional contents and also quantity of materials of objects that feed on pests may result in ideal breeding conditions for harmful insects. Monitoring of the entire interior of a museum and efforts to grasp pest habitat is essential. Methods for grasp pest habitat include regular surveillance measuring by using mold measuring equipment and pest traps (Fig. 2.11), and also extrapolating based on accumulated reporting from the persons who have detected pests. In the case of reliance on reporting, explaining the objective to various staff employed by

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Table 2.1 Major pests that damage cultural objects

Insect pest

Materials that are susceptible to pests

Silverfish

Paper (especially glued areas), woolen fabrics, cotton, linen, silk

Casemaking clothes moth

Fur, woolen, silk, cotton, linen

Anobiid

Wood, paper, fur, woolen

Powderpost beetle

Wood, bamboo, rattan

Carpet beetle

Fur, woolen, silk

Booklouse

Paper, mold

Cockroach

Wood, paper, fur, cotton, linen, silk

the museum is essential to obtain their cooperation. After attaining measurement results, pest number and type are confirmed and if there is a tendency to increase, together with other potential causes, such as temperature and relative humidity, are analyzed. Then necessary insect and mold proofing treatment shall be implemented and/or a facility improvement plan shall be created to prevent intrusion and breeding of pests. Concurrently, a clear policy must be indicated for action that should be taken when pests are found. Such a policy shall pertain to eating and drinking spaces for visitors, and also concerns for considerations that should be taken for drinking and eating spaces of staff also. In recent years, such a method is often explained as an environment management method called IPM, which stands for Integrated Pest Management. In this book, “Improving the Environment for Conservation of objects” is touched on the IPM in Chap. 3, Sect. 3.1.

2.2.1.5

Vibration

In addition to vibration generated during transportation, other causes of vibration are earthquakes, walking of museum visitors, and also vibration transmitted through air from air conditioning vents, and also from street traffic and train travel on nearby rails. Vibration and shock during transporting of objects is measured by a small acceleration meter attached inside the transport packaging case (Fig. 2.12). Characteristics of vibration frequency and vibration amplitude, as well as acceleration from shock are determined by data analysis acquired during transport. From such analysis, packaging and transport methods are considered to make continuous improvements (Saunders et al., 1990). Considerations for high precision require as many measurement case examples as possible. In the worst case, if the work piece is damaged during transportation, the data can be used to verify the transportation process that has had a significant impact on the damage if the packaging case is equipped with vibration and shock gauges. However, it may not be possible to identify the cause

2.2 Monitoring and Evaluation of Environment

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Table 2.2 Major molds that damage cultural objects. Quoted from Takatori, Keisuke: Bunkazai ni miru yuugaikabi to yuugaikabi no tokusei, Bunkazai no tyuukingai, 63, pp. 3–8, 2012 Classification

Characteristics

Examples

Thermophilic mold

Mold with an optimum growth Neosartorya, Byssochlamys, temperature range of 37–50 °C etc

Psychrophile mold

Mold that can grow at low temperatures of 10 °C or less

Mesophilic mold

Molds that are widely Many of the molds that are distributed in the environment likely to occur on cultural and have an optimum growth properties belong to this group temperature range of 20–30 °C

Parasitic mold

There is a mold that attaches to living organisms and absorbs nutrients from them

Hygrophil mold

A group of molds that are likely to occur when the humidity is high

Cladosporium, Alternaria, Fusarium, Trichoderma, Rhizopus and Aureobasidium

Drought resistant mold

A group of molds with an optimal relative humidity in the 85–97% range

Aspergillus and Penicillium

Xerophilous mold

A group of molds with an optimal relative humidity in the 65–90% range

Eurotium, Aspergillus restrictus, and Wallemia

Osmophilic mold

Mold can grow under high osmotic pressure

Eurotium, Aspergillus restrictus, Wallemia, Chaetomium and Chrysosporium

Odor-producing mold

Molds often produce secondary metabolites as it grows. One of them is odor

Among the molds, Penicillium is one of the most odorous molds, and Trichoderma, Chaetomium, and Mycelia are among them

Chromogenic mold

Those that produce dyes, which are secondary metabolites, outside the cells as the mold grows

Fusarium, Penicillium, Cladosporium, Epicoccum and Trichoderma

Specific component lytic mold Mold that damages materials containing specific components such as hard proteins and lipids

Chrysosporium, Scopulariopsis and Phoma

Fusarium, Phoma, Cladosporium, etc.

without clearly knowing the exact time of the accident and what was being done at that time. In the case of earthquakes, damage to objects may be lessened by protective usage of such as seismic isolation devices, anti-tipping devices, fall prevention fence structures in shelves, and wooden storage boxes. Past big earthquakes verify the effectiveness of such protective measures. As a measure to protect the building structure

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Fig. 2.11 Pest habitat survey by trap method

of the museum from earthquakes, some museum facilities have already implemented seismic isolation for both the museum building and the museum floor. Earthquake seismic intensity is measured by seismometer, however, almost no museum facilities are not actually monitoring of it. Most often, earthquake intensity and ways of swinging are verified based on data indicated by governmental agencies such as the Japan Meteorological Agency, upon which earthquake countermeasures are taken. It will also be possible to verify specific seismic countermeasures using artificial seismic motion using official seismic data.

2.2.2 Necessary Guideline for Optimization In order to realize genuine safety in housing and displaying objects, minimization and/or elimination of the aforementioned indicated causes is essential. Organizational implementation is important for achieving such appropriate circumstance by setting concrete target values for security measures and also disaster preparedness for earthquakes, fires, and water flood damage, as well as concentrations of pollutants in air, the insect pest habitation, levels and changes in temperature and relative humidity, and level and dose of illuminance of display lighting. Furthermore, achieving a safe environment of the storages and exhibition rooms must be done concurrently with

2.2 Monitoring and Evaluation of Environment

37

Fig. 2.12 A device for recording vibration and shock during transportation

making it safer and easier to use the facility by staff and visitors. In order to realize space of both a housing environment backed with safety and excellent design, clearly indicating a concrete policy and target values for conservation is essential (Kamba, 2005).

2.2.2.1

Temperature and Relative Humidity

The recommended average temperature is 22 °C, and with slight seasonal fluctuations, the temperature is within the range of 18–26 °C that is 22 ± 4 °C. Facilities and/or objects with a comparatively high history of relative humidity should be 60 ± 5 °C, and for facilities and/or objects historically of or being in comparatively dry relative humidity should be 55 ± 5 °C. Daily fluctuation in one day should each be within 3 °C and 5% to realize an appropriate environment. National treasures and important cultural assets must be in accordance with this conditions except that the temperature fluctuation must be smaller (Thomson, 1978). On the other hand, the temperature inside the museum during the summer is set higher than before, depending on the outside temperature during the day. Such setting of the temperature reduces discomfort experienced by museum visitors due to extreme temperature differences between inside and outside the museum, and is also effective in suppressing energy consumption. Relative humidity throughout the

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four seasons is to be adjusted to a set target value. In case of setting of temperature and relative humidity must be varied, stabilizing relative humidity must be prioritized over temperature. For humidity fluctuations not fitting within the target range, setting up of more mild range than the target value to a level of 40–70% so that at least the percentage fits within this range. For example, relative humidity in a 50–60% environment is to be level 1, and 40–70% is to be level 2 (Table 2.3). Measuring of the environment is done by using both the thermo-hygrograph and data logger. The thermos-hygrograph is used for determining relative humidity on the site, and a data logger is used for analyzing measurement data.

2.2.2.2

Illuminance and Total Dose of Light Exposure

Appropriate illuminance and total dose are based on the material’s vulnerability of objects to light. By keeping the total dose of light exposure for one year at constant, time can be extended for the portion of reduced illuminance. The degree of flexibility of illuminance levels and irradiation time within this range is given. On occasion, within the same fiscal year, in cases that the total dose must exceed the regulation, a corresponding portion is used from the next fiscal year, whereby the portion used in advance is subtracted from the next fiscal year, however, it is necessary to be strict in determining such processing. Maximum illuminance and total dose values are indicated as guidelines by material and object classification from the Agency for Cultural Affairs and International Council of Museums etc. (Tables 2.4 and 2.5). Both illumination and dose indicate the permitted limit, therefore lighting and exhibition planning are designed within the range of permitted values.

2.2.2.3

Insect Pests Inhabitants

The basis of harmful pest management is to segregate habitats away from exhibition and storage space. The aim of such management must not be killing all of insects, bacteria, and/or mold resulting in an environment in which such pests do not inhabit. The basis of habitat isolation is thought to involve ensuring limiting the intrusion of pests from outdoors. Such habitat isolation is thought to be achieved by thorough prevention of bringing into the museum objects and/or materials believed to be contaminated by harmful insects and/or mold. However, some degree of harmful pest intrusion must be taken into account. Reducing environmental conditions preferred by harmful pests on a daily basis and also creating an environment to keep such pests at a distance and making the environment difficult for the pests to inhabit is important. Concrete guidelines to follow include maintaining the relative humidity within the appropriate range, avoidance of dust accumulation which makes for easy nesting of microorganisms, and thorough hygiene management for food and restrooms. Use of a climograph is a convenient method for understanding the deep relationship tying the occurrence of molds to annual transitions in relative humidity change (Fig. 2.13).

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Table 2.3 Environmental assessment at three levels based on relative humidity values Temperature/humidity graph

Climograph

Class [Class 1] A level where the relative humidity value is within the range of 50–60% throughout the year. An environment where most cultural objects are safely stored [Class 2] A level where the relative humidity value is within the range of 40–70% throughout the year. It is necessary to be careful but there is a possibility that it can become Class 1 with small improvement [Environment requires attention] A level that does not fit in the range of Class 2. The feature is that there is no stable period throughout the year. Often requires major refurbishment

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Table 2.4 Illuminance guideline presented by various institutions (unit: lx) Vulnerability Category

Institution Agency for ICOM Cultural Affairs

The United G. IES States—Japan Thomson Conference on Cultural and Educational Interchange (CULCON)

1970

1977

1977

150 or less 50 (especially vulnerable within 30 days)

1985

Very sensitive

Textiles, tapestries, watercolor paintings, Japanese paintings, drawings, manuscripts, stamps, printed materials, wallpaper, natural history specimens

Relatively sensitive

Oil 150 or less 150–180 – paintings, tempera paintings, frescoes, leather goods, bones, horns, ivory, wood, lacquer wares

200

75 (8 h a day, 300 days a year, integrated illuminance 180,000 lx h)

Not sensitive

Metal, stone, – glass, ceramics, gems, enamel, stained glass

–

–

–

100 (10 h a 50 day, 50 days a year, integrated illuminance 50000 lx h)

1987

–

50 (8 h a day, 300 days a year, integrated illuminance 120,000 lx h)

On the climograph, monthly average relative humidity is plotted with temperature on the vertical axis and relative humidity on the horizontal axis.

2.2 Monitoring and Evaluation of Environment Table 2.5 Allowable illuminance and exhibition period for each field of objects at the Tokyo National Museum enacted in January 4, 2005

41

Very sensitive objects Ukiyo-e wood broch print

50 lx or less within 4 weeks per year

Textile

80 lx or less within 8 Weeks per year

Ink wash, watercolor painting

100 lx or less within 4 weeks per year*

Drawing

100 lx or less within 4 weeks per year*

Calligraphy、manuscript

100 lx or less within 8 weeks per year

Polychrome sculpture

100 lx or less within 3 months per year

*In actual operation, the display may be held once one and a half year, and the period will be extended accordingly Relatively sensitive objects Oil painting

150 lx or less within 3 months per year

Lacquer ware

150 lx or less within 3 months per year

Wood, bamboo

150 lx or less within 3 months per year

Uncolored sculpture

150 lx or less within 3 months per year

Ivory, horn and shell

150 lx or less for a year

None sensitive objects Earthenware, ceramics

300 lx or less for a year

Stone

300 lx or less for a year

Metal

300 lx or less for a year*

* The

sword will be exhibited within 3 months a year for regular maintenance

2.2.2.4

Concentration of Atmospheric Contaminating Substances

Air pollutant are not only hazardous to one’s health, but also contaminate and deteriorate the materials of art objects. Accordingly, while it being ideal to make concentration of such air pollutants to be zero, a realistic guiding principle is to reduce the concentration to the level making deterioration difficult to occur. The concentration of air pollutants intruding from outdoors generally decrease in the deep interior of buildings. Concentration of contaminants released from building materials in museums differ depending on the type of the material in a building. Cooperation efforts in preventing air pollutants from intruding from outdoors and also cooperating in eliminating sources of indoor contaminants are fundamental.

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Fig. 2.13 Climograph concerning mold growth and annual transition of relative humidity

From a long-term standpoint, levels considered to have small impact on objects are purported to be less than 30 ppb ammonia, 20 ppb formaldehyde, 10 ppb formic acid, and 40 ppb acetic acid (Sano et al. 2010). At the Tokyo National Museum, we are applying 5 ppb ammonia, 50 ppb formaldehyde, 10 ppb formic acid, and 50 ppb acetic acid as the maximum target values, and we are making cooperative efforts to have fewer in everywhere (Tables 2.6 and 2.7).

2.2.2.5

Vibration

As a guideline for vibration that potentially impacts objects, the below measures are given. First, vibration for which there is generally minor awareness is caused by air flow of air conditioning equipment. Air flow velocity sent from air conditioning vents when large are effective for climate control, however, less wind pressure against objects is desirable (Hama et al., 2013). Air flow speed is considered to be at a safe level for works if it is controlled to be a few centimeters per second at extremely close proximity to objects. Next, even though not occurring on a daily basis, vibration during transportation of objects must be considered. Vibration and shock depend on transporting environment such as machinery used for transporting objects by truck and airplane, and also road conditions for transport. In general, characteristic frequency of vibration of air suspension in trucks is 2 Hz and between

2.2 Monitoring and Evaluation of Environment

43

Table 2.6 An example of guidelines for concentration of atmospheric contaminating substances. The table is modified and quoted with permission from the author. Quoted from Sano et al. (2010): Hakubutsukan Siryo Hozon Ron – Bunkazai to Kuuki Osen (Conservation of Museum ObjectsCultural Objects and Atmospheric Contaminating Substance-), Mimizuku-sha, Tokyo Atmospheric contaminating substances

Unit

Short-term exhibition

Long-term exhibition

Long-term storage

Ammonia (NH3 )

ppb