Dear IAQ members,
Lately, a second version of the chapter on Museums, Libraries, and Archives
has been released. Now located in the Chapter 21 of the application book of
ASHRAE. Cecilcy Grzywacz and James Druzik from the Getty Conservation
Institute, Stefan Michalski and myself from CCI were involved with other
HVAC engineers.
The most important change in the chapter was actually the incorporation of
the issue of airborne pollutants.
Unfortunately, I didn't see the last version of the document before its
publication. After the "fais accomplie" I realized that some texts never
get updated or revised properly. Consequently, the chapter got published
with some amounts of mistakes related to the pollutant sections. The
biggest is probably the explanation of the Table 6 "Air quality targets.."
(which was not written by me). For those who will be interested to get a
copy eventually, you should consider these corrections:
p.21.6.
Tetreaul's (1993) should be replaced by Tetreault's (2003)
p.21.7
Unfortunately, there is no text related to SO2, NOx and Ozone which are
important pollutants in museum indoor env.
p.21.8
Other pollutants in Table 5: it should be Table 2
and the paragraph starting by "Table 6 combines..." should be replaced by:
Table 6 combines pollutant information on object deterioration, troposphere
benchmarks, ambient levels in polluted urban areas or in polluted indoor
environments, and reductions achieved by buildings with and without HVAC
systems. The maximum levels of airborne pollutants allowed in rooms or in
enclosures are based on the approaches of Lowest Observable Adverse Effect
Dose (LOAED) and No Observable Adverse Effect (NOAEL). The concept of NOAEL
is applied only for acetic acid. These approaches have been suggested by
Tétreault (2003) Critical review of detailed in situ observations combined
with laboratory studies has provided a substantial amount of quantitative
information concerning adverse effects of pollutants on materials.
Extensive sets of LOAED and NOAEL are available in Tetreault 2003. Table 6
provides performance targets for the levels of airborne pollutants for most
collections. Hypersensitive materials are excluded from the Table 6 for
common sense reasons. They are just too sensitive to ambient pollutants to
justify their preservation in the room level. The hypersensitive objects
and their respective harmful pollutant are untarnished lead for acetic
acid; silver for hydrogen sulfide; most unfaded sensitive colorants such as
curcumin and alizarin crimson for nitrogen dioxide and ozone; stress
vulcanized natural rubber for ozone and; unfaded sensitive colorants,
newsprint and leather for sulfur dioxide. The reductions noted for
buildings with and without HVAC filtration systems are based on current
experience with buildings, as compiled by Tétreault (2003). This
compilation is based from different authors such as Druzik (1990) and
Nazaroff et al. (1993). The reduction of the Outdoor pollutants' levels by
HVAC without proper filters or simply by natural ventilation can be caused
to low infiltration, low makeup air fast adsorption by indoor materials'
surfaces
(text not edited)
new references related to the new paragraph above:
Druzik, J. R., M. S. Adams, C. Tiller, and G. R. Cass "The Measurement and
Model Predictions of Indoor Ozone Concentrations in Museums." Atmospheric
Environment 24 (1990), p. 1813 - 1823.
Nazaroff et al. 1993 Airborne Particles in Museums, Research in
Conservation volume 6. p. 22 - 39.
P.21.9
In Table 6 "for performance target of" should be deleted and in Note
"NOEAL" should be "NOAEL"
and in the main text "see Table 4" should be deleted.
For my point of view this sentence is in conflict with Table 6:
" For long-term preservation, levels of airborne pollutants should be below
0.03 :g/m3 or less than 1 :g/m3 for inorganic gases and fine particles and
in the double- or single-digit :g/m3 range for organic carbonyl
pollutants."
P.21.15
In the reference section, the references Tetreault 1993, Tetreault 1999a,
and Tetreault 2001 should be deleted.
This ASHRAE Chapter 21 is available in pdf file:
http://resourcecenter.ashrae.org/store/ashrae/newstore.cgi?itemid=16997&view=item&categoryid=456&page=1&loginid=416005
My book in Airborne Pollutants in Museums, Galleries and Archives: Risk
Assessment, Control Strategies and Preservation Management, Canadian
Conservation Institute. Ottawa (2003) will be released in early January
2004. The delay is due to the French version (not done by me). The English
version is already edited and formatted as seen at the latest IAQ
Conference in Norwich. It contains the rational of Table 6 of ASHRAE
chapter 21 (without mistake) and specifications for dust and gas filters
adapted for museums needs.
By the mean time, you are invited to read my latest papers on Guidelines
for Pollutant Concentrations in Museums at this link below:
http://www.cci-icc.gc.ca/whats-new/news31/pollutants_e.shtml
Jean Tétreault
Senior Conservation Scientist/ Part Time Acting Manager of the Preventive
Conservation Section
Canadian Conservation Institute
1030 Innes Road Ottawa, Ont. K1A 0M5, Canada
email: [log in to unmask]
Internet sites:
CCI Web: http://www.cci-icc.gc.ca/
Indoor Air Quality in Museums and Archives: http://iaq.dk/
|