Using vacuum cleaners in display cases

Imogen Herford <imogen.herford [at] bl__uk> writes

>...  However I am interested to know if it is commonly
>understood that vacuum cleaners should never be used in any account,
>in any situation, even in empty display cases. ...

Perhaps it is too much to assume that dust, that is, particulate
matter suspended in air, is accumulating inside the display case. Is
that the problem? If the vacuum cleaner is going to be used to
remove normal dust and dirt, then the vacuum cleaner seems to be the
obvious, inexpensive, efficient choice of tool. The vacuum cleaner
should have a HEPA filter, and if one obtains a long enough hose,
then the body of the machine never needs to enter the cabinet and
beat against furniture or artifacts. Even if the motor body doesn't
ever enter an exhibit space, the motor body has to be leak proof for
dust. The idea of the vacuum is that the dust goes into the nozzle
and is trapped in the filter, so that only clean air exits the
machine.  Leaking vacuums must be repaired or replaced with ones
that don't leak.  I used to work at an enormous Canadian museum and
we wore out two or three vacuums a year in our efforts to clean
exhibits and keep them clean. The people I talk to can hardly
imagine that vacuum cleaners could be either the least bit out of
style, or controversial, in 2007.

Are there problems cleaning with vacuums? Of course one needs to be
extremely careful when moving oneself and a vacuum hose and a brush
inside a display cabinet. As I recall, most cabinets were cleared of
artifacts before we vacuumed them clean. Artifacts were cleaned
using vacuums, separately, when the vacuum was the right tool to
remove loose dust. Showcases are normally too tightly packed to
allow a human inside with a vacuum and brush. We also had lots of
open exhibits to clean, which could not have been cleaned and kept
clean in any other manner, than with a vacuum and a brush.

Vacuum power can be controlled on good, modern vacuums, so brutal
strength from the machine is not a necessary evil implied by
"vacuum" cleaning. Of course there can be problems bashing into
things with the wand and the hose, which is one more reason to
demand that competent people be found and trusted to do your
cleaning.  You have to have people who are productive, agile,
motivated, and careful.

So, no, it is not commonly understood that vacuum cleaners should
never be employed to clean exhibits. Just the opposite. They are
exactly the tool you need to use for dust removal.

One can also take a few steps to minimize the deposition of dust,
much of which arrives with visitors and outside air. Keep doors
closed, keep windows closed, have a robust fan at the entrance air
lock to blow loose dirt off of people's clothes, a sort of positive
pressure entrance vestibule. Not every museum can have one of these.
Within the building, one can seal the showcase as well as possible,
then pressurize it by pumping in filtered air. By creating a
"positive pressure showcase" you can effectively eliminate the
accumulation of dust in your showcase. The air is pulled through a
filter and pushed into the showcase by a quiet muffin fan. Because
of the positive interior pressure, all the leaking zones push away
dirty air, so the interior stays clean. Only clean air enters. Even
very large exhibits can be kept almost completely free of dust this
way.

Of course one has to inspect and replace filters from time to time,
and fans can wear out after 10,000  or 20,000 hours. Whenever we had
a large showcase that would remain filled for more than, say, a
year, or permanently, we tended to seal and pressurize it. First of
all, it kept the artifacts clean, and secondly, it eliminated the
risk of damaging objects while cleaning them, and thirdly, it saved
lots of money having staff clean the exhibits. Win, win, win. There
is a fourth benefit: workers thought the managers were more clever
for keeping the exhibits clean in the first place, as museum workers
have a lot of work to do that is more fun than vacuuming.

James Hay
Senior Conservator
Furniture and Decorative Arts
Canadian Conservation Institute
1030 Innes Road
Ottawa K1A 0M5
Canada


                                  ***
                  Conservation DistList Instance 21:11
                   Distributed: Sunday, June 17, 2007
                       Message Id: cdl-21-11-002
                                  ***