By Mary Stroka
Stepping into The Field Museum is a breathtaking experience, as the Stanley Field Hall’s physical immensity greets the visitor through its high, vaulted ceiling covering exhibits scattered over its half-acre of floor space, including SUE, the largest Tyrannosaurus rex fossil ever found; two towering Northwest Coast Native American totem poles; and taxidermist Carl Akeley’s “Fighting African Elephants.”
Just as impressive is the vast collection of artifacts and specimens the museum houses and the engineering that keeps each of these 26 million items (only one percent of which are on display) and the more than 1 million annual visitors comfortable throughout the year. Originally opened in 1894 as the Field Columbian Museum at what is now the Museum of Science & Industry, construction on The Field Museum’s permanent home in Grant Park began in 1914. Visitors have seen the collections on that site since May 2, 1921. Just this March, The Field Museum, assisted by Chicago-based non-profit Delta Institute, earned LEED Gold certification for Existing Buildings Operations and Maintenance (EB O+M) — it is one of only two museums nationally to have earned that distinction.
The building now consists of more than 480,000 square feet of exhibition space on three floors and, since 2005, 186,000 square feet in the two underground levels which form the Collections Resource Center (CRC). The CRC facility provides contiguous space for artifacts, including spark-proof storage for specimens stored in alcohol and cryogenic storage to preserve botanical and zoological DNA and tissue samples, along with wet labs, X-ray labs and histology labs. In total, the building spans an impressive 1.3 million square feet.
The incredible undertaking of providing a facility that cares for these millions of artifacts and visitors falls on the shoulders of Earl Duncan, The Field Museum’s chief engineer since May 2001. He has overseen significant changes in the building’s engineering since he started as an assistant engineer on the midnight shift 31 years ago.
“I’ve kind of outlasted everybody,” he quipped. “I’ve done every job I expect the engineers to do now.”
The projects have included replacing high-pressure boilers installed in the 1940s with new, low-pressure boilers as part of the 2003 central plant project; implementing an air conditioning system in 1975; adding new air handlers with variable frequency drives on the roof; and installing solar panels.
The central plant project involved replacing boilers, chillers, fire pumps and air-handling units. The publication ENR Midwest declared
The Field Museum’s construction of a new central plant “Project of the Year” in 2003 because of the challenging logistics through which the Museum was able to fit new equipment on the small campus and allow for further growth of collections space while remaining open to the public.
The team is currently working on the design of a new rooftop air handler for the southwest quadrant of the building and finishing up a 15-year installation of thousands of sprinklers throughout the building, which is at 95-percent completion at the time of this writing, and should be completed by December 2016.
One of the neat things about The Field Museum’s engineering is its use of ice storage tanks as chillers. The Field Museum is one of the few institutions that uses ice to cool its building, and it uses 48 ice storage tanks to do so. These were installed with the 2003 central plant project. As ice in the tanks melts, it is pumped through to the building’s air-handling units. Cooling through ice instead of chillers is less expensive, Duncan said. The Museum runs its four chillers only at night, two for the building and two for making ice, when the electricity is cheaper due to supply and demand. “Every project we do is done to conserve energy,” he said.
“Chilled water in the building 365 days a year keeps artifacts cool and comfy,” Duncan said. They have decoupled the heating and cooling so they can have climate control year-round.
Many of the artifacts, especially those in the Ancient Egypt exhibit, require specific levels of humidity and lighting both for the preservation and look of the presented artifacts. So the engineers create “microclimates” that pinpoint particular artifact cases and allow the conditions to fit the desired parameters, including the ability to change the dew point for the air blown into the case. Loaned exhibits are kept in three designated halls that the staff have designed to be able to more finely control the air.
Director of Facilities Ernst Pierre-Toussaint said The Field Museum also tracks its progress on conservation in a number of ways, primarily focused on its use of resources such as energy, water, consumable purchasing, and waste. The Museum tracks its water and energy use through sub-meters and records them monthly on Energy Star’s Portfolio Manager, a benchmarking and tracking tool offered by the U.S. Environmental Protection Agency. This and other tracking metrics, such as purchasing and recycling, can be used to create a baseline and continuous profile of the environmental impact of the building.
“We’re trying to operate as smart as we can to be more