There's been a study using sophisticated light meters that show just how much UVB is absorbed when wire mesh and fly screen is between a UVB light bulb and a reptile. Here are the results:
"If 5mm zinc plated mesh is placed in front of the tube, a 15-20% reduction in output is seen. (Compare Series 1 with Series 2).
25-35% losses occur with fly screen of the type often used for chameleon vivaria (Series 3). "
This is the site where the test results were reported:
http://www.uvguide.co.uk/fluorescenttubemeshtests.htm
If, however, the holes in the screen are big enough, then the reduction in light won't be significant. The usual rule of thumb is that 1/2 inch holes won't hurt.
If you happen to have a screen that has holes smaller than 1/2 inch, you can simply cut a hole in it over the area where the turtle basks and then the light can go through unobstructed.
Tahnee, where the distance between the UVB bulb and the basking turtle is concerned, the safe distance is completely dependent on the type of UVB bulb you are using. If for instance, you are using an MVB bulb, then anything closer than 12" would be dangerous. If you are using a compact fluorescent, it depends on the bulb and you should follow manufacturers recommendations closely as they vary quite a bit. If you are using a tube fluorescent, then you usually can put the bulb closer than 12". For some tube fluorescents, as close as 8" is considered fine.
Posted: Sun Jan 20, 2008 12:09 pm UVB ?
