Is this cage for use with a snake or a lizard? In my experiences, such screen covers for basking lamps are worse off than having the bulb itself exposed.
If it is just a bulb, a lizard that jumps and tries to cling on to it, will have a very difficult time in doing so, and will simply fall off- with exposure time to the skin being a fraction of a second.
Whereas, in the use of such a screen cover, that metal that is only inches from the head source absorbs heat very easily(most metals are great at that), to the extent where the metal may often be close in temperature to the light itself(after remaining on all day). By having mesh around the bulb, this makes for an easy place for jumping and holding on to, and lizard claws can sometimes even get stuck in such a screen, which increases their exposure time to such a hot surface temperature. You are going to have a greater occurrence/chance of nasty thermal burns by using a metal screen around a light like that, as the animal has a greater period of contact with the piping hot temperatures, when compared to a light bulb by itself.
Snakes on the other hand, I suppose it doesn't make much of a difference, as they will be able to come in contact with virtually the same temperatures, whether it be the bulb itself, or the metal screening around it, therefore if the snake is able to access the part of the enclosure with the heating element, I think you have just an equal chance of thermal burns.
I recommend you use one of those infrared temp guns and measure the temperature of the screening around that light bulb, after being on for a couple of hours. You will find that the metal heats up very easily, and can very easily burn the animal(much like how you can burn yourself very badly by touching a pot that has been over a flame). Or put a piece of metal out in the sunlight on just an 80 degree day. After several ours being exposed to natural sunlight, that metal object will have heated up to a temperature significantly hotter than the air temperature.= I have gone out and measured the temperature of the sidewalk on a 75F sunny day, to be 145F... Think about the temperatures of a piece of metal held less than a few inches away from a 100watt light bulb????
Just thought I'd throw in my two cents, as I have done a fair bit of experimenting with temperatures, being a monitor keeper(and having to supply basking temperatures of up to 160F). I have found that screens around bulbs are more hazardous to lizards than without screens, and for snakes, the burn potential is still there...
Cheers Everyone,
Bob
treemonitors.com
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TheOdatriad

