Among the structures sitting on the 100-acre lot at Fort Meade is the Library of Congress (LOC) Book Storage Facility. As the LOC collection grows, so does its need for more storage space — it receives approximately 8,000 new items every day. The Book Storage Facility currently consists of six modules and five cold storage rooms, with construction funding for a seventh module approved in the Fiscal Year 2023 budget.

The modules boast 35-foot-high ceilings with rows of bookshelves that reach up to 30 feet. Books, maps, manuscripts, photographs, microfilm and music are stored in one of 10 different-sized boxes and placed on one of six shelves of various sizes. There are three separate climates carefully maintained by the AOC, with temperatures set to 50, 35 and 25 degrees Fahrenheit, all at 30 percent relative humidity, to accommodate the various materials. Staging areas, set up outside of the cold storage rooms, allow items to acclimate to the varying temperatures and prevent condensation so they can be safely moved from one climate to another.

Two people working on equipment.
Chris Saylor and Rick Webb service a fan motor for one of the cold storage rooms.

LOC staff are charged with overseeing the collection — receiving, sorting and cataloguing each piece — while AOC staff are responsible for efficiently operating, repairing and maintaining the modules. AOC staff oversee the dehumidifiers, chillers, boilers, humidifiers, pumps, cooling towers, and all other mechanical and electrical equipment required to preserve the LOC's priceless collection.

The items in the LOC collection are tracked through an automated book system that enables LOC workers to quickly find and retrieve them. The process of "checking out" a book is a bit more involved given the distance it has to travel from shelf to hand, but items are transported between Fort Meade and Capitol Hill every day.

Given the height of the shelves, LOC workers often must use specialized lifts to retrieve items. A super-flat floor was installed to prevent the lifts from leaning and turning over, knocking over the thousands of carefully catalogued boxes. Magnets were also installed in certain spots in the floor, a few feet from the end of aisles, to slow the lifts as they enter the main aisles. Every detail of the modules is centered on protecting history in its various forms and preserving it for generations to come.

The first module was completed in 2002. From that year until 2017, the AOC maintained the modules through contract support. Beginning in 2017, the agency was able to add full-time AOC employees to manage the facilities. There are now two shifts overseeing the facilities with recent funding provided to add a much-needed third operations and maintenance shift.

Moving from contract support to AOC staff has resulted in better response times for correcting equipment issues, which has resulted in better environmental conditions. AOC staff have also found ways to create significant energy improvements, leading to a 30 percent reduction of energy consumption from 2016 to 2022.

The new third shift will add enough staff to perform all maintenance, repair and operations at Fort Meade, which is an ongoing task. The Book Storage Facility has increased in size by almost 40 percent since 2017, including the addition of a second heating and cooling plant, and will continue to grow with Module 7.

Two people standing near a ladder.
John Smith and Derrick Smith repair the automatic door closer in Module 4.

With the growth of the facility has come a significant focus on identifying the heating and cooling loads for the HVAC equipment and modifying the way the AOC thinks about matching the required energy loads. The building loads are driven by the outside air dew point, which is the temperature the air must be cooled for it to become saturated. A higher dew point results in a greater amount of moisture in the air and a higher energy load at the facility. AOC staff now incorporate the dew point into their daily operational plans and have modified controls to respond to this important parameter correctly.

What makes it so important? Preservation standards. For AOC staff to preserve the LOC's collection, the air must be cooler and dryer at the Book Storage Facility than in a normal office. This requires special attention. The AOC's work is always a balance between its important historic preservation mission and planning for future improvements. The work at Fort Meade is no different.

Future improvements will prioritize energy efficiency goals. Plans include the installation of special dehumidifiers that will provide for the reuse of up to 60 percent of energy in the facility as well as the implementation of on-site power generation through solar panels and energy storage to maximize energy savings and resiliency.

On Capitol Hill and beyond, the AOC's dedicated employees take pride in maintaining all facilities entrusted to their care and serving those that work to preserve the priceless items housed within them.


A great article to not only read but think about how my life could fit into this mold. I am a retired pipefitter and worked in paper making plants, college storage units, many medical facilities. All of these needed to control moistures and tempture at the same time. Dufault to maintain. Thank You.

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