Concrete dust

Johann Alcock <jalcock [at] slv__vic__gov__au> writes

>We are currently researching the effect of concrete dust on storage
>products, oils on canvas and object collections.  There appears to
>be very little written on this topic.  Has anyone had experience
>with collections that have been affected by concrete dust?  What are
>the issues that need to be considered in their treatment?   Where
>paper based storage materials are affected by concrete dust is it
>possible to clean them effectively or is it best to replace them?
>Any help would be appreciated.

The main problem with concrete dust is its alkalinity.  Toshiko
Kenjo, Kenzo Toishi, Chie Sano and other Japanese authors have
researched this subject over the past 30 years, with emphasis on
problems posed by new concrete museum buildings.  As the concrete
ages (carbonizes) most of the alkalinity gets lost.  They
demonstrated that a great variety of objects can be adversely
affected by the alkaline emissions of new concrete.

My only personal experience with this problem was the accidental
discharge of cement powder through the HVAC system in a US museum.
All objects (paintings, furniture, tapestries, decorative arts) were
covered with fine cement dust.  We cleaned the objects and all
surfaces of the building by vacuum cleaning, with the aid of soft
brushes, in the case of tapestries through screens.  Care had to be
taken that the dust from uncleaned areas was not stirred up.
Therefore the exhaust from the industrial vacuum cleaners was led
outside through long hoses (we also had doubts that the filters
would be able to hold all of the fine dust).  This was a few years
ago and we have not heard about any adverse effects on the objects.

If the dust is from "old" concrete it probably poses no threat and
is more of a nuisance, like all dirt (at least I was not able to
find anything in the literature that would indicate otherwise).  One
thing I would definitely avoid with both, new and old cement, is the
introduction of moisture. Good luck with your research,

Frank D. Preusser

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                  Conservation DistList Instance 12:48
                 Distributed: Monday, November 30, 1998
                       Message Id: cdl-12-48-003
                                  ***