Caution urged when considering LED light sources for light-sensitive materials

Many thanks to Dale Paul Kronkright for his very useful posting on
the risks of using LEDs and selective colour fading.  However, I
would like to ask for people's views on the use of LED lighting in
some other situations. Dale describes the situation in museums which
recognise the need for UV and IR filtering and where accurate colour
rendering is of considerable importance. I assume this means that
such filters are in place and lighting systems can be chosen on the
basis of their colour output, even if this means they are more
expensive.  I work with 500 museums in the southwest of England, the
majority of which are staffed and run by elderly volunteers and
receive no financial aid. Their annual turnovers from admissions and
shop sales are often measured in hundreds, not thousands, of pounds
sterling and their electricity costs are usually the second highest
item of expenditure after building rent.

Many of these museums have elderly lighting systems (more than 30
years old) which are a mixture of unfiltered daylight, fluorescent
tubes, halogen downlighters and tungsten lamps, some of which are
inside the old cast-off museum cases they have acquired.  For these
museums, introducing blinds or UV film for windows, changing the
angle of spotlights and moving items to more sheltered display areas
as well as introducing the concept of temporary display effect a
considerable improvement in the conditions to which the objects are
exposed. LED lighting, which provides UV free light (using a UV
meter to test, not relying on the manufacturer's description) has
the added bonus that it reduces the museum's energy bill and
provides an additional benefit as visitors are increasingly keen to
see the museum's commitment to saving energy (and resources) and
reducing their carbon footprint.

For the past year we have been trialling LED lighting in one gallery
of one of these museums.  I would welcome any thoughts or experience
from other conservators about the potential for using LEDs in poorly
funded museums and in a world where the consumption of energy and
materials are being considered with increasing commitment. How
significant is the damage caused? How concerned should we be to
preserve the (remaining) colour balance in an object which has
already spent 10 years in atrocious lighting conditions?

Helena Jaeschke
Conservation Development Officer
Royal Albert Memorial Museum
Exeter Ark
3 Exton Road
Marsh Barton
Exeter EX2 8LX
+44 1392 665951


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                  Conservation DistList Instance 23:40
                  Distributed: Friday, April 16, 2010
                       Message Id: cdl-23-40-008
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