MORTEN RYHL-SVENDSEN

The School of Conservation, Copenhagen

SOLVING OFF-GASSING PROBLEMS IN DANISH MUSEUMS, CURRENT KNOWLEDGE AND METHODS

Abstract:

Often small Danish museums don't have conservators among their staff. Instead, local craftsmen, volunteers, students and the like usually handle the museum objects and build up new exhibitions. As a result, common building materials such as fibreboard, masonite and solid wood, together with a wide range of fillers, adhesives and paints are most often used. Currently, the smaller institutes have no, or very little knowledge, about the problems that might arise from the usage of these materials. Very few museums include information about selecting good construction materials in their preservation policies, and in fact many have not even defined what is a 'good' or 'bad' material. This is also the case with some of the larger museums and institutes.

In spite of this, a few conservators and curators in Denmark are aware of the problems, however, they have a substantial task ahead in order to spread the word throughout the country at other museums and teaching colleges. In addition, although the problems are understood in theory, there is a great deal of uncertainty when it comes to carrying out practical solutions. Fortunately, the subject is now being addressed in Denmark, for example, a workshop at the School of Conservation in Copenhagen was held in 1997 on Air Quality in Museums, and this will be repeated this summer. Also, Nordisk Konservatorforbund (The Nordic Section of IIC), has just recently started a workgroup on Indoor Climate and Exhibition Conditions.

In summary, four ways in which Danish museum staff today are tackling the problems of off-gassing from construction materials are:

1. to substitute the bad materials with better ones
2. to raise the ventilation rate in closed spaces
3. to filter the air with activated charcoal or other scavengers
4. to block the pollutants route to the artefacts with barrier foil.

All four methods work well, but in order be able to to profound evaluate construction materials before use in museum exhibitions or storage facilities, there is a need for precise test methods which can detect not only that 'something' is polluting, but also what it is.

As the need and demand for this kind of air-quality analysis is growing, the National Museum wants to expand its activities into this field. As the laboratory at the museum already performs gas chromatographic analyses (identification of vax, oils, lacquers, etc.), so it seems reasonable to suggest implementation of a method based on this technique.

The National Museum therefore is planning to construct emission test facilities including a test chamber as part of the conservation departement laboratory in a soon future.