Most of us have been to a garage sale or two in our lives or walked down the aisles of our local thrift store. Undoubtedly you’ll find used computer monitors, gaming systems, and appliances that may have one glaring thing in common besides being a little outdated: a yellowish-brown color that appears to be a practical paint-job joke.
You may have noticed this phenomenon in your home as well if you own appliances, electronics, or other items made primarily of plastic. Most of us chalk it up to the idea that this is a natural process as the plastic ages over time. While this is partly true, it also has a lot to do with the science of plastics, light, and how they interact.
What the sun can teach us about UV light
The sun rises and lights the world we live in, but did you know that sunlight is only 44% visible light? The rest of the light spectrum comprising the remaining 56% is Ultraviolet (UV) and Infrared light – both of which are invisible to the human eye.
Over time though, the effects of UV light exposure on certain materials can be very noticeable. Notice the picture above of a pair of basketball shoes and how the clear plastic has been stained yellow? This happened over a period of time due to outdoor UV exposure and heat. It’s ok if you go check out your sneakers right this second!
Places you may find UV light damage in your home
If you’re at home or even at work, look for the plastic face-plates on wall outlets and cable lines. Chances are if they were installed even a few years ago, they aren’t white
anymore, but more of a cream, yellow, beige, or butter hue. Discolored plastic faceplates can really be an eyesore that detract from even the most superb paint-job.
If you have an older home, your kitchen may have laminate or plastic countertops. You may have thought they were yellow when you bought the place (maybe, right?), but chances are they haven’t always been that color. Faded countertops can really detract from a kitchen, especially if you’re going for a “clean” and modern feel.
After you’ve examined your shoes, gaming systems, and countertops, mosey on over to the fridge and grab something cold to drink – you deserve it! But go ahead and pay particular attention to the interior of your refrigerator. One of the most common UV damaged appliances is the fridge interior – particularly true if you own an older model. Yellow fridges can make food appear less than appetizing!
What causes Indoor UV damage?
The sun isn’t the only UV emitting light source. In fact you probably have a light source that emits UV radiation in nearly every room in your house. ¬Common UV emitters include xenon lamps, deuterium lamps, mercury lamps, halide arc lamps, and fluorescent lamps.
Inside a lamp, electrical discharge excites a gas – emitting ultraviolet radiation. UV rays hit a special dye covering the bulb, which absorbs UV radiation and emits visible light. In this process, most of the UV radiation is absorbed (or otherwise blocked) by the fluorescent dye and/or the glass of the bulb. Yet, some does get through.
Most plastics typically reflect the majority of UV light that hits them. However, if there are trace elements of catalyst residues (chemicals used in manufacturing of the plastic), then the plastic will absorb UV and accelerate the discoloration process.
Exposure to UV light starts a process called photodegradation, which takes place alongside thermal oxidation (from exposure to heat). These processes break down the structure of the plastic. Once this process starts, it feeds on itself and starts a continual cycle of degradation.
Protect your plastics with Diffuser Specialist and NaturaLux™
NaturaLux™ products are uniquely designed to reduce the glare of fluorescent lighting and eliminate UV radiation. For doctors’ offices, schools, and supermarkets these lighting filters are the most cost effective way to create a safer and more visually soothing environment.
Learn about how NaturaLux™ filters can protect the appearance of your plastics and how they’ve transformed indoor work and learning environments with fewer headaches, less fatigue and increased productivity.