Simplified Environmental Recommendations for Collection Storage

Managing RiskWhile there are a number of factors included in the broad concept of the storage environment – temperature, relative humidity, light, air pollution, radiation, vibration, space use – temperature and relative humidity are significant because they are always present and have a direct impact on the rate of decay in nearly all materials.

We realize that managing storage and display environments for preservation involves an understanding of many things – material types (organic, inorganic, and composite), the basics of material decay (chemical, biological, mechanical), the role of temperature and RH in the rate of decay for specific materials, and equilibration rates. The local climate, building envelope, mechanical system, and storage enclosures need to be considered as well.

Even so, sometimes it is nice to have a simple reference point when you consider:

  • How good (or bad) are the existing storage conditions?
  • What storage conditions are required for the materials in the collection?
  • What storage compromises can be safely made for the materials in the collection?

The generally accepted “ideal” environment – a flat line 70°F (21°C)/50% RH- just doesn’t work for all collections and is difficult for mechanical systems to achieve and maintain. This issue offers a double-sided reference to guide collection care and facility staff as they plan and operate the collections environment.

The first side of the reference is a Suitability of Storage Environments for Collection Materials chart that was developed to provide guidance to a team of architects, engineers, facility and collection staff engaged in planning new storage facilities for a mix of collection types. This chart identifies the suitability of three broad types of storage conditions – Room, Cool, and Cold, each with different temperature levels and safe RH specifications.

The second side of the reference is a Safe and Risk Zones for Temperature and Relative Humidity chart that provides a simple reference point for the effect of environment on material decay. Red zones indicate high risk, yellow indicates caution, and green zones are considered safe for most materials.

Click here to download the reference in PDF format

The format is similar to IPI’s Media Storage Quick Reference (MSQR) which was developed for the management of photographs, films, audio and video tapes, CDs, and DVDs. The MSQR is available for free download or purchase at A variety of other storage guides are available for free download on this page as well.