IPI's research continued to highlight the complex relationship between temperature, relative humidity, and the moisture content of collection material. These elements were clearly the primary drivers effecting the three major forms of deterioration—natural aging and mechanical and biological decay.
Although the importance of temperature and relative humidity was well documented, there were few resources available to help preservation staff understand the impact of their real-life environments on their collections. Recognizing the need for a way to transform hard data into understandable information that could be easily applied to the daily task of preservation, IPI developed Preservation Metrics.
The first was the Preservation Index (PI), which estimates the rate of chemical decay that would occur in organic materials in given temperature and relative humidity conditions. The PI was a useful guideline for materials in static conditions while the Time-Weighted Preservation Index (TWPI) incorporates the change in conditions over time for a more accurate representation. Mechanical damage metrics determine the amount of dimensional change in an object based on equilibration moisture content (how dry, how damp, and how much fluctuation between the two extremes). The risk of mold growth is derived from temperature and humidity data over time, and metal corrosion from the periods of high moisture content or dampness. Because the Preservation Metrics could assess the impact of the environment on all types of collection materials, IPI's focus expanded to include managing environments for long-term preservation of all collection types.
IPI decided to create an accurate and reliable device that would facilitate the collection and interpretation of environmental data over extended periods. The first Preservation Environment Monitor® (PEM®) was available in 2000 and the new version, PEM2®, came out in 2007. These loggers are in use in hundreds of institutions around the world and have a user satisfaction rate of over 95%.
IPI's first environmental management software program, Climate Notebook®was released in 2004 after two lengthy field trials. The software offered the field a comprehensive tool that graphed data, detailed the effect of the storage environment on over fifty specific materials and collection types, and generated reports with analysis of preservation quality. For some institutions, it became difficult to effectively search and organize data and associated information from a large number of locations. This led to the development of MyClimateData, designed to provide quick access to centralized information about collections, shared access to updates, and a wide range of search and organizational options via the web. A second web-based program, PEMdata [1], was developed to accompany the release of the PEM2®. This site provided streamlined environmental management and a simple way to store and graph data on the web. IPI is currently developing eClimateNotebook, a web application that will combine the strengths of Climate Notebook, MyClimateData, and PEMdata into a single, uniformed platform with several options for small, medium and large institutions.
IPI’s first collaboration with energy-efficiency consultants Herzog/Wheeler and Associates in 1998 evolved into a long-standing partnership and marked the beginning of IPI’s commitment to developing sustainable preservation practices. The objective of that first shared project was to document the operation and energy use of HVAC systems at the Library of Congress and the New York Public Library in order to improve the preservation quality of storage environments while reducing energy costs. This approach became the foundation of IPI’s current environmental management approach.
Our experience demonstrated that significant energy-saving opportunities exist, but it also revealed the formidable challenge of coordinating the often conflicting management strategies and work habits of preservation and facilities departments. In response to this challenge, IPI and Herzog/Wheeler refined a process to facilitate interdepartmental communication and shared management of the storage environment.
More than ever, cultural institutions are feeling the need to adopt new preservation strategies. The growing financial, social, and environmental pressures for “green” and sustainable operations require an approach that allows for dynamic preservation environment. IPI hopes to guide the field in implementing safe and sustainable preservation practices that will enable institutions to balance stewardship of collections with fiscal realities and global environmental responsibilities.