Physical Environment
The physical environment in which library materials are housed is the largest single controllable factor affecting the usable life of the entire collection.
Temperature and Relative Humidity
The temperature of the Kelvin Smith Library is kept between 68-72 degrees Fahrenheit and the relative humidity between 40- 55%. Although most people are comfortable within this environment, some do feel chilly. Cooler temperatures and lower humidity GREATLY increase the longevity of the entire paper, film, and magnetic-based collections this library houses. At a stable lower temperature and humidity, more of the collection will remain physically available for use by future generations of students and researchers. Please remember to bring along a sweater if you feel too cold! 
High humidity can allow an outbreak of mold such as this to occur in a collection. It also encourages certain insect infestations, especially when combined with warmer temperatures.
Lighting
All visible light is damaging to books and paper over time. The UV portion of the spectrum present in natural light causes especially rapid fading and deterioration of cloth, paper, and leather materials. The warming effect of sunlight coming through the windows onto the shelved books also causes them to deteriorate at a much faster rate. If you are using study carrels in the third floor stack area, please help protect this collection by remembering to close the window shade next to your study area before you leave.
Summary of Criteria for the Conservation Environment
taken from "Conservation Environment Guidelines for Libraries and Archives", by William P. Lull
- RELATIVE HUMIDITY
- Paper: 40-45%
- Film: generally 30% RH, but can vary with material
TEMPERATURE - Paper: 60-65 F for storage
- 65-70 F for occupied areas
- Film: Same, or lower if possible
- Temperature goals should generally be subordinated to humidity goals and stability
LIGHT - Storage: 1-5 Footcandles (11-55 Lux)
- Reading /Work Areas: 30-60 Footcandles (330-660 Lux), but only short exposures for paper and other light-sensitive materials
- UV Content: <75 microwatts per lumen, <2 to 4% UV
- IR Content: Limit with light levels or dichroic reflector lamps