Light & Radiation
One of the biggest threats to certain collectibles is nothing more then the stuff we use to see it! Here is how to prevent light from fading or degrading your collection.
The first thing you need to know about light is that it is made out of exactly the same stuff as x-rays, gamma rays, micro-waves etc. and other deadly stuff. The only difference between UV rays that are used to sterilize -kill the bacteria on- things -and the look of a "violet -gently bedewed in the early morn" is the frequency / wavelength of the light. It's like the difference between a soprano's voice (the dangerous, high-energy, destructive UV end of the spectrum) and a base voice (the IR 'infra-red' end.) This is the end of the spectrum that makes a nice crackling fire so welcoming on a cold winter's night. I'm NOT drawing any inference between the relative pleasantness of a shrill little harpy and a great warm teddy-bear of a man -but feel free to ponder it yourself.
The point here is that ANY radiation -even the relatively benign stuff our eyes recognize as visible light- will damage stuff. Let's take a priceless medieval tapestry as a hypothetical example. If -for some reason- you wanted to fade it to white and use it to make a nice bed for you dog, you would do well to get a hold of what they call ionizing radiation. Easily done, all you have to do it spread the tapestry out facing the sun someplace well above the earth's magnetic field and it's outside of its atmosphere. If you don't have a spaceship at your disposal, you are out of luck, but the rest of us are IN luck. Our planet protects us from this ionizing radiation stuff -and a damn good thing this is. The far right side of the spectrum -the very highest soprano of the radiation scale -is deadly to living things -and not very nice to dead things either. Anything more complicated then rock is broken down to its component bits in this ionizing radiation. Let me emphasize this. UV light is part of that stuff they call ionizing radiation and such breaks down organic matter. Examples of organic matter include most pigments. Oil paints, water-colors, and your kids crayons are all made from organic pigments. YOU are another example of something made out of organic matter, unless you have had certain kinds of surgery. (Even silicone is organic, but its preservation is well outside of my purposes in this article.)
For that matter, if you were somehow able to spread a priceless medieval tapestry out in direct unfiltered up-in-space sunlight, the sun's rays would not only fade it, but it would turn it into nothing more then a whiff of gas and a little carbon ash in short order.
But to return to our example or deliberately fading a priceless tapestry. If you don't have a spaceship, your next best option is to spread it out in the most convenient equatorial desert. Africa is full of such, but your backyard on a sunny day would serve. If it's a rainy day, your next best option is to spread it out under some special and very expensive UV lamps that are used by set-decorators and special effects people. Or you could use simple fluorescent lights. Not as fast -but they will eventually get the job done. You say you have no florescent lights, but you have a lot of good-old regular light-bulbs you want to use -what they call "incandescent bulbs"? Forget about it. Incandescent lights don't give out enough UV light to amount to didley. They do a fair job with the visible light and good job with the infra-red light -the warm cuddly end of the spectrum.
Furthermore, if you were to misguidedly put a pane of clear plastic over the top of your tapestry -just to keep it flat- you would slow the process down even more. Plastic is opaque to UV radiation you say? Yep -this is what I'm saying. PLASTIC IS LARGELY OPAQUE TO UV LIGHT AND GLASS IS NOT! (But you will only slow down the process. You can NOT stop it entirely.)
So to summarize, if you can see it -there is visible light bouncing off it and into your eyeballs. If light bounces off of it, there must be light falling on it. And if there is light falling on it, there is some degradation -perhaps very little and very slow, but there is degradation.
WHAT TO DO -on the cheap.
All of this is to say that common sense will take you further down the UV protection road then all the fancy -and expensive - plastics, films, and special light bulbs. You MUST keep your collectable out of direct sunlight. You SHOULD keep it out of any bright light. If there are a lot of fluorescent lights in the room where you keep your collection, you MIGHT buy some plastic tubes or sleeves to cover the bulbs. But wait a minute, if your fluorescent bulbs are behind a plastic panel -perhaps in recessed lights, you are already there! Remember, plastic is opaque to UV light!
WHAT TO DO -to spend money.
Suppose you have done all you can in the room wherein reside your valuables -plastic between the fluorescent bulbs and your art-work, acid free mounting materials, things mounted on the walls so sunlight doesn't fall on them (and remember -the sun shines differently in the winter then it does in the summer -probably comes farther into your room then it does in the summer) etc. But there is a window. It's a good window -lets in pleasant light -maybe nice, cool, even northern light and a little fresh air too. You don't want to brick it up and you don't even want curtains. Here is what you do. Get yourself a piece of acrylic plastic somewhat bigger then the window -say 20% bigger- and hang it from the ceiling on two pieces of chain. Put it 4 or 5 inches away from the wall and you can reach behind it to open and close the window and allow for fresh air to get in. You might have noticed such things in museums. Museum people call 'em baffles. They limit the UV and do so unobtrusively. Or use that reflective film they make to cut-down on summer's heat. Both of these things are sold at the local home-improvement store, but if you need a piece of acrylic bigger then 24" x 48" you might need to open the phone-book.
WHAT TO DO -to spend a lot of money but to do things right:
We have to agree that glass is simply better looking them plastic. This is not to say that plastic hasn't some decided advantages -it's lighter, stronger, and less dangerous etc. -not to mention that it is UV opaque, but it simply is not as nice to look through as glass. But glass is transparent to destructive UV radiation. There is a rather snooty company that makes all sorts of treated glass. The stuff ain't cheap but for valuable artwork, it is a must. It will run you between 3 and 5 times the cost of the glass you buy at your local home-improvement store. (Take heart -the stuff they make for museums costs 10 times as much.)
What makes it worth this much? Well, it is covered with a special and proprietary plastic film that kills the UV light. Then it is acid-etched just the tiniest little bit to cut down on glare. Then it is given another coat of secrete-stuff to kill the glare even more. It cuts just like regular glass, but given the cost of either Museum or Conservation glass, it might behoove you to know what you are doing with a glass cutter.* If you don't know, the good news is that there are all sorts of people who know this and they even know about acid-free this and archival-quality that. They arethe framing people. (And they are able to deal with the snooty company that makes the expensive glass.) Check out....
Professional Picture Framers Association
American Association of Museums
The Guild for Fine Art Care and Treatment Standards
*A good glass cutter will cost you all of $5.00 at the hardware store and is not hard to use, but there is a knack. You might see if you can't find someone to teach you, or buy a big sheet of glass and practice by making it into a bunch of NEAT smaller sheets.