Volume 18, Number 3 .... September 1996

Comments from a Conservator on Climate Control

(This note was one of several postings on the Conservation DistList in early August discussing environmental control. It has been edited slightly for publication.)

I want to express my apologies at opening this particular can of worms; my original intent was not to start a major correspondence. It was simply to alert the person who was so happy to hear that the Smithsonian scientists said that institutions could save millions on environmental control, that everything is more complicated than it at first appears, that any institution needs to do serious homework or talk to someone who knows the field and the particulars of its situation, collections, etc.

However, the can is open, and I believe it holds some more interesting worms than I had expected. Mr. Tumosa (one of the other contributors to the discussion. ed.) expressed his shock at the "visceral rather than intellectual nature" of the criticism aimed at CAL's work and claimed that the press release in question (see WAAC Newsletter Volume 17, No. 1, Jan. 1995, pp. 19-28) was not meant to substitute for serious intellectual inquiry. The press release was, however, sent to people whose job in the museum world is not intellectual inquiry but balancing budgets (as far as I know it was not sent to conservators). As I read it, the bottom line of the press release was saving millions of dollars, not conveying research results, and the statement that ordinary household air conditioners are sufficient for museum climate control in no way derives from any research. (Point of clarification: the air conditioners referred to in the press release were "heating and cooling systems used in grocery or retail stores". ed.)

I would like to go beyond our mutual vilification, as much fun as it undoubtedly is for bystanders, and open some serious discussion on the relationship between science and conservation, the differences between the professional responsibilities of conservators and scientists, and the chasm between research data and recommendations for collections management. These are important matters, and seldom discussed.

One example: Mr. Tumosa's statement that representing the museum environment as a series of microclimates is "in contradiction to everyone's experience." It may make messy science, but the fact is that every building, whether mechanically controlled or not, is a series of microclimates, and collections are purposely arranged to take advantage of those microclimates. Lobbies, boiler rooms, rooms with windows, rooms with no exterior exposure, classrooms, and auditoriums are all part of museums. Studies have shown wide variation in RH and temperature even within one room. Environments within glazed frames and exhibition cases are of course quite different again. Knowing what these natural microclimates are, designing some new ones, and arranging collections in them based on susceptibilities is a major tactic in collections management.

Another issue that separates scientists from conservators is the fundamental notion in the field of conservation that every object is unique. This is not to imply that physical laws do not govern the behavior of objects, only that each particular object has its quirks stemming from peculiarities of its own construction and history as well as from its cultural meaning.

Take for example the class of coated wooden objects. Data exist on the dimensional response of various species to RH changes, and the changes in behavior with certain coatings (although not specifically the coatings that conservators use or many of those on actual objects). Yet the magnitude, direction, and rate of dimensional change for an object depend on a host of factors including the orientation and position of the wood on the tree, the number and relative grain orientation of joined pieces, the elasticity, permeability, and adhesion of the coating(s) and the number and orientation of surfaces to which it has been applied,the environmental, maintenance, and treatment history of the object, the amount of surface exposed by original shaping and by insect tunneling, etc.

Another set of variables governs the degree to which any dimensional change affects the physical integrity of the object, and a different set determines how the cultural or aesthetic meaning is affected by the damage. The use of the term damage is in itself a cultural one, not a scientific one. Given a totem pole and a telephone pole, a panel painting and a shop sign, Babe Ruth's baseball bat and George Washington's bed frame, how can any set of data be used to make recommendations on environmental control?

If data on material response were the primary factor on which decisions on museum environment were to be made, then the US Constitution should get the same level of care as the earliest known menu from the Waldorf Astoria that mentions Waldorf Salad.

In the interests of not writing another book, I will only say that institutional matters like staffing levels, budget, building construction, and a host of others are also as important than any of the above.

In other words, it is not logical to base recommendations for any collections management parameters only on data from materials testing. I did not mean to say ( in previous posting. ed.) that the Smithsonian team had not published their research data; my problem is that the arithmetic that went into the money savings figures has not been published, nor has much of the discussion that is needed to illustrate how their data got them to their conclusions about what museums should do. This is the discussion that is missing.

One additional issue: scientists are responsible for the integrity of their data; conservators are responsible for the well-being of objects. Tempting museum administrators with multimillion dollar savings based on the idea that the field of conservation has been mistaken about environmental control is something that conservators feel is irresponsible. Are there savings to be had? In some cases, yes, but at the least let's remember that you can only save millions if you are already spending millions. Are there improvements to made in environmental control that don't cost a fortune? Of course, if they haven't been made already. Are there now data that change the way collections should be managed? I don't think so. When the Smithsonian museums follow their own staff's advice and publish the results, we can all learn something.