BIRDS & LIGHTING - Compact Fluorescent Lights
BIRDS & LIGHTING - Compact Fluorescent LightsCOMPACT LIGHTS
A very popular form of fluorescent lighting of late is the compact fixture. These devices are designed to replace conventional incandescent bulbs in screw in fixtures. From a general lighting application, these devices are a boon to the consumer in both color rendition of illuminated areas, and in energy savings. However, for the bird owner or breeder, they fail to provide adequate amounts of necessary UVB radiation for Vitamin D synthesis. An example of this device is shown below:FIGURE 1 - THE COMPACT FLUORESCENT
The construction of compacts is very similar to the conventional fluorescent tube. Instead of a linear design, the tube is shaped in a convoluted array, shrinking the size of the entire package to a much smaller area. All of the electrical circuitry (i.e., starter, ballast) is built into the base of the compact device itself. Therefore, it is quite self contained. Most of the devices on the market are designed so that the fluorescent tube itself can be replaced as it loses brilliance, or begins to flicker.
The reason that these devices are inadequate is quite simple. Long fluorescent tubes have the advantage of a large interior surface area in which to place the phosphor coating. Some even have special indentations to maximize this area. Due to the design considerations of the compact, this area is limited, and in most cases equals only the surface area to be found in an 8" to 12" slimline tube. To compensate for this diminished area, the selection of phosphors is made to maximize the lumen output of the lamp in a color balanced area of the spectrum. So called “full spectrum” compacts such as those sold by Ott and Sylvania, merely have a high Color Rendition Index (CRI) that often sacrifices total lumen output for the size of the device over aesthetic considerations. In reality, these devices are “wide spectrum”. Those kinds not advertised as such correlate to the same output as a conventional cool or warm white fluorescent tube. The total amounts of UVB produced by any of these lamps is miniscule, and so weak in effective power output that it is not even a measurable consideration more than an inch or so from the lamp tube. Even at that distance, the bulk of the output is within the UVA range, which has nothing to do with vitamin synthesis.
I include the small 8" and 12" slimline lamps that are found in under cabinet and desk lamp fixtures in this category also for the same reasons. While the “wide spectrum” compacts are adequate for improving the general lighting considerations of the room, and also for bird applications, they should not be mistaken for full spectrum lights, and should never be used in applications where there is a consideration of Vitamin D deficiency and the use of light. These lamps should only be used in applications where the bird has an adequate exposure to unfiltered sunlight, or a diet which contains sufficient amounts of Vitamin D supplementation. For more information on the energy
saving considerations of compact devices, I refer the reader to:
Copyright 1999 by Patrick Thrush
