Anna Serotta and Andrew Smyth
In the spring of 2012, The Metropolitan Museum of Art began a large-scale renovation of galleries, offices and storage areas in The Costume Institute, which is located directly below the galleries of the Egyptian Art Department. Vibration from construction activities poses a serious risk to museum objects, and the fragile nature of objects in the Egyptian galleries makes this collection particularly vulnerable. To safeguard the collection, a project team including curatorial, collections management, and conservation staff, in collaboration with a group from the Department of Civil Engineering and Engineering Mechanics at Columbia University, worked together to assess the risk to the collection on an object by object basis and developed a range of preventive conservation strategies. This paper will discuss the methods and procedures that were developed not only to protect the artworks but also to allow visitors continued access to as much of the collection as possible during the work period.
Before the renovation, tests were carried out to determine the amount of vibration that would be caused by the demolition of both structural and nonstructural elements in the construction zone. Different tools and demolition methods were tested in various locations to assess which would create the least vibration; at the same time, techniques for mitigating vibration were evaluated. The article discusses the implementation of these mitigation solutions, which included isolation of objects and pedestals with Sorbothane and other vibration-dampening materials. Testing also revealed that shelf design and pedestal shape and material contributed significantly to the degree of vibration amplification. Case studies will be presented that illustrate the response of particular installations to vibration and specific solutions devised for each scenario. For some objects, isolation was not possible; deinstallation decisions and logistics will be presented.
During initial testing, a monitoring system to measure vibration levels and to automatically communicate this information to the project team was developed; this system, which used wireless communication, was implemented throughout the effected galleries before the start of demolition. Automated alerts were sent via e-mail or SMS (text) message to the project team when defined vibration velocity thresholds were exceeded. The corresponding vibration event signals were recorded on a central server for reference and review. The vibration sensors were placed on gallery floors, directly on objects, or on shelves and pedestals and display case decks. The rationale for the general vibration thresholds used in the project, which were adjusted depending on the sensor location and context, is discussed. The quantitative feedback provided by the vibration monitoring system was augmented with daily observation and regular hands-on assessment of vibration levels throughout the two-year project.
Although much information was gained through limited initial testing, the actual construction project often produced unexpected vibration and consequently mitigation solutions had to be adapted. Preliminary observations about the response of objects, installations, and the building itself to various demolition and construction activities will be shared. The dynamic nature of the construction project required great flexibility, and constant dialogue between all members of the project team, the construction department, and contractors was essential to the overall success of this project.