The environment in ReCAP has been optimized for the storage of library and archival collections, focusing on cellulosic materials, including paper (the majority of ReCAP's contents) and film, as well as the variety of plastics that are common in 20th century audio and video media formats.
The modules are formed by a substantial masonry wall with heavy insulation and vapor barriers, and served by an HVAC system with particulate and gas filters. There are no roof penetrations or wall penetrations to the outside from the modules and specials seals are used at the docks and doors within the modules.
ReCAP maintains an annual operating environment with a Time-Weighted Preservation Index (TWPI) of 180 or better, compared to a TWPI 40-50 for standard library stacks. The humidity in the modules is maintained at 35%, +/- 3%, and temperature is cycled between 50-59° F over the course of the year to minimize power usage during peak demand periods and maximize the benefits of free cooling from the outdoor environment. ReCAP's separate cold-storage vault is set for 35° F, +/- 3° and 25% RH, +/- 3%. Sensors placed throughout each module and the film vault constantly monitor temperature and humidity and alarms are sounded when conditions exceed tolerance.
More information on the preservation environment standards in use at ReCAP are available from the Image Permanence Institute. ReCAP's environment is designed and managed to achieve good ratings on all of IPI's metrics, while maximizing TWPI. Our current operating program achieves a TWPI between 180-200, and we are working on new models that will maintain or even raise our TWPI while also decreasing our energy usage. Initial tests in 2014-15 resulted in stable TWPI while reducing power consumption by more than 10%, and a more formal study and implementation program will begin in 2016-2017.
ReCAP is fully protected with automatic sprinklers. The sprinklers are located at the ceiling above each of the storage aisles as well as within the book storage racks at three different elevations. This sprinkler system, with the help of a 1500 gallon per minute (gpm) diesel fire pump, is designed to deliver over 1800 gpm of water directly to the source a fire in order to control the fire.
The facility is equipped with a complete fire protection signaling system with detection and alarm capability. It monitors the readiness and operation of the sprinkler system (tamper and flow) and provides for early-warning smoke detection via 32 smoke detectors in return air ducts and at ceiling height.
Alarms and trouble conditions are reported directly to the Princeton University Public Safety Department and Plainsboro Township Fire Department. The sprinkler system and smoke detectors were installed and maintained by Oliver Sprinkler Company, King of Prussia, Pa.
Access to the ReCAP is controlled by a key card access security system. Princeton University and Corporate Security Services (CSS) upgraded the system in 2010 and monitor 24/7.