An enclosure for displaying artwork, historical documents, and artifacts that require controlled atmospheric conditions is provided that is low cost and less cumbersome compared to existing microclimate enclosures. The enclosure has a frame construction that is easy to set up, maintain, and monitor with a hypoxic/anoxic microclimate that protects against, oxidation of its contents, pests, and bacterial growth. The enclosure is suitable for: paintings, works on paper, ephemera, textiles, mineral specimens, archeological metallic artifacts, animal skins and other organic items, rubber and polymers, and items susceptible to insect damage. A method of testing and servicing one or more enclosures is also provided.