In Conservation we prove that something is acceptable, or best, for an
application before we make a recommendation.  One has only a few
chances, or possibly only one, when preserving historical artifacts.
Mistakes can ruin materials and/or the evidence of how a thing was made.

We are not defending human beings against criminal charges.  Materials
are not innocent until proven guilty.  Materials and techniques are
suspect until proven safe.  We want facts that tell us a technique or
material will do the things that are claimed for it, and that no
unforseen damage will occur from it use.  Think of the process from the
standpoint of the irreplaceable subject of the experiment, rather than
that of the material to be advertized, bought or sold.

Timothy Vitale
Paper and Photography Conservator
& Preservation Consultant