Protective Effects of Anoxic Enclosures
Previous studies have suggested that while many light-sensitive pigments and dyes will benefit from being displayed in an oxygen-free environment, some pigments and dyes will change via photo-reductive processes or show no differences whatsoever. These earlier studies were based on a limited set of materials. Some studies also used oxygen scavengers, which might not have attained low enough oxygen concentration to produce meaningful results, or did not report oxygen concentrations to which samples were exposed, making comparison to current results difficult. In these earlier studies, temperature and relative humidity were seldom controlled to the extent they would be in museum display conditions. Thus, as important as this work is, the full magnitude of the photo-reductive extent on colorants cannot be estimated. Recent work by Lerwill (2012) filled in many of these gaps but has likewise created more questions concerning anoxic benefits.
Anoxic Enclosures at the GCIThis area of research applies nearly 15 years of Getty experience in designing and building environmentally-controlled, oxygen-free display cases, to photochemical damage research. The initial experiment consisted of a pair of matched display cases, one with a normal atmosphere and one with a nitrogen atmosphere, irradiated under banks of MR-16 lamps. Temperature control was achieved with a recirculating, liquid-cooled, closed loop system, which in turn allows for stable relative humidity conditions, and oxygen concentration was measured in the anoxic environment.
Page updated: November 2012