Greetings:

The American Institute for Conservation presented an excellent two-day workshop on Exhibition Lighting as part of its annual meeting last month.  The workshop presented a lot of really good information, including information about compact fluorescents and LEDs. 

Stefan Michalski of the Canadian Conservation Institute presented a table that provided the general characteristics of light sources and compared all of the sources that are available.  With respect to UV emissions, compact fluorescents will emit between 100 – 150 microwatts/lumen of UV while white LED (light emitting diodes) emit between 0-75 microwatts/lumen.  For compact fluorescents a custom made filter will be necessary while filters are not required for LEDs.

Both types of illumination are very useful at short distances such as in display cases and relamping frequency is relatively low.  But there are drawbacks with both types of lamps:  Compact fluorescents are not easily directed in a sharp beam and although the LEDs can be easily aimed there are still technical problems that make them a challenge for use in many museums. 

These technical problems, cited in Stefan’s chart, and discussed in an excellent presentation by Richard Kerschner, the head of conservation at the Shelburne Museum in Vermont, include problems with the color rendering index (CRI) which varies from 70 (fair) for current all white lamps to 90 (good) for mixed color LEDs (although the white lamps are expected to improve over the next few years); variable lamp lifetime; a drop of lamp intensity early in the lifetime of the lamp; and poor color homogeneity of the beam.

It is my understanding that fluorescent lamps rely on UV to work, so they would put out enormous amounts of UV light.  That being said, they use phosphors to convert the UV to visible light, and how much escapes is something I don't know.

I'd recommend going with LED lighting rather than UV as it can be made UV neutral and is much more efficient than fluorescent lamps.