Medium density fiberboard

Harriet Woolmore <harriet.woolmore [at] cls__glasgow__gov__uk> writes

>It is my understanding that MDF (Medium Density Fibre board) is not
>used in museums in the United States of America for both
>conservation and health and safety reasons. At Glasgow Museums,  MDF
>is widely used both in the construction of and as dress panels
>inside display cases. ...

We researched the issues around the use of MDF in the walls of our
two building projects, the now open National Gallery of
Victoria:Australia and the gutted and renovated National Gallery of
Victoria:International which is to open in December after 4 years of
construction.  The issues are complex but you have to use something
that will last, take paint well and do the job of holding pictures
up.  We looked at alternatives, including non-formaldehyde boards,
plywoods and etc and finally settled on the (then) new European
Standard MDF.

This standard specifies the amount of formaldehyde present at a
level considerably lower than was common a decade ago.  Trade union
action and advice on health and safety issues around the inhalation
of dust from cutting MDF created guidelines for cutting boards and
the handling and disposal of MDF dust.  Your trade unions will be
well aware of these as the guidelines emanated from them in the U.K..
I understand the recommendations evolved during the time the EU
standard was being formulated, so if anything, they are probably
overly cautious, but adhering to them didn't seem to cause any
difficulties for us. All MDF cutting was done on site within a
designated area, the machine operators wore protective clothing and
breathing equipment and the dust was disposed of separately from
other waste.  It wasn't particularly onerous and I think was just
common sense hygiene.

Note that cutting any wood product where fine particles are produced
carries inhalation risk which should be carefully controlled. MDF
isn't any worse than a lot of woods and there are some pretty toxic
hardwoods you'd want to be even more concerned about than MDF.
Cutting tools such as panel saws with EU certification are also much
better at dust capture than previous versions and we have been
updating many of our power tools for this reason.

Once MDF is installed and particularly after it is painted,
offgassing ceases to be an issue as the museum will have several
changes of air per hour which avoids the buildup of the small
amounts of formaldehyde that will be released.  We have also used
fibrous cement sheeting, which is a very inert material, over the
MDF in many areas.

EU standard MDF is not as nasty as its predecessor was and we
couldn't find any better alternatives on a balance of risk basis.
For example, the non-formaldehyde wheat straw based board is bound
with cyanoacrylate which releases cyanide gas when combusted. Also,
we couldn't get a good enough paint surface on it.

The design and construction of cases, and particularly sealed cases
where alternate environmental conditions are required, needs a
different strategy but I wouldn't rule out MDF in cases- it depends
on how you use it.  An easy way is line the inside of the MDF with
fibre cement sheeting (James Hardie Industries).  This is easy to
work, very inert and takes paint well. Offgassing of paint is
another issue.

Thomas Dixon
Chief Conservator
National Gallery of Victoria
Melbourne Australia


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                  Conservation DistList Instance 17:4
                   Distributed: Monday, June 23, 2003
                        Message Id: cdl-17-4-011
                                  ***