In avoiding such situations, the first challenge lies in determining the historic nature of the instrument. The following guidelines for determining historical significance are excerpted from those of the Organ Historical Society.
Any organ or organ case in the United States which was built prior to 1850 may be said to be of major historical importance. Its significance increases with its age, its rarity, and the extent to which its components remain in unaltered condition.
Any substantially unaltered organ built prior to 1900 which is an outstanding example of a particular style or of a particular builder's work, or is unique in some other way (e.g., the only remaining example of a particular builder's work).
The above criteria may also be applied to certain 20th-century organs, especially if they represent an important period in a given builder's work, or milestones in the development of a particular style.
The second challenge is to produce a true restoration of the instrument. Securing the services of a reputable restorer who is sympathetic to the guidelines set forth by the Organ Historical Society will help to ensure that all facets of the restorative work remain faithful to the intent of the builder.
By virtue of our inheritance of these instruments, we are now their custodians. As such, it is our obligation to care for them in a manner which allows us to benefit from the achievements of the past. By preserving instruments which possess musical integrity, we also preserve models for the continued development of the organ building art.
CRCCM endorses the use of the complete guidelines for the Conservation and Restoration of Organs, produced by the Organ Historical Society.