Natural Light Matters: A light level survey at The Museum of Modern Art

The Museum of Modern Art (MoMA) in New York City maintains an active program for 3 million visitors per year, including an average of 50 on-site exhibitions. As attendance climbs, the Museum has sought an expanded range of locations in which to display its collection. Spaces such as the lobby and public hallways, which were not originally designed to meet the Museum’s exacting climate standards, have nonetheless been identified as potential sites for exhibiting artworks. Discussions between conservators and curators about the benefits and risks of displaying art in these spaces, and concern about the preservation implications for the collection, prompted members of MoMA’s Conservation Department to devise a plan to monitor light levels, temperature, and relative humidity in non-gallery public spaces throughout the museum. Conservators from different specializations reviewed floor plans and identified locations that were both popular choices among curatorial staff and thought to have light levels in excess of standard gallery levels. Preliminary light readings were taken to identify additional areas for monitoring. The monitoring team identified sixty-three locations of interest. An inexpensive and unobtrusive model of logger, the Hobo U12-012, was chosen to collect data on light, relative humidity, and temperature. A monitoring plan was devised to rotate nine loggers among the selected locations for four fourteen-day periods: once in each season. Successful execution of this project depended upon careful planning and thorough communication with stakeholders. The project plan was unanimously approved by security, facilities, and each department’s chief curator. Over the course of the year, the monitoring team rotated the loggers on a bi-weekly basis, and made minor adjustments to location as necessary to avoid unduly impacting the aesthetics of a given gallery. At the end of the survey, the data was analyzed by conservation scientists. Reports and raw data for each location are available electronically and in hard copy. Organized by location, each entry includes image and mapping documentation of the site, graphs of light levels, temperature, and relative humidity, and statistical analysis. Each location’s report includes the minimum, maximum, average, and standard deviation for light, temperature, and relative humidity. One of three grades was assigned to each location and season: no risk, low risk, or significant risk. The data and analysis serve as powerful tools for identifying inappropriate locations for works that are sensitive to environmental fluctuations. The survey data has proved to be an essential resource, and a second iteration of the project, to incorporate the Museum’s latest expansion, is planned for 2019.