While researching my project, I found out how harmful UV light can really be.
I wanted to provide the other participants and attendees of the science fair with practical information that will help them better protect themselves from harmful UV rays. In the duration of someone’s time outside, they might be unaware of how much damage UV light might be doing to them. This can lead lead to many types of fatal or dangerous skin cancers.
My project shows how well various fabrics protect us from UV light. I am hoping that the people coming to my project will leave with more knowledge to prevent damage from UV light. This report will be about what UV light is (and most things to do with it), how UV beads work, and different fabrics and how to tell if they are UV resistant.
I will also be stating information on what my manipulated and responding variables are.Manipulated VariableMy manipulated variable is the different fabrics that I will be testing for absorption and/or reflection of UV light. These fabrics include lighter polyester, darker polyester, a black 100% cotton t – shirt, a white 100% cotton t – shirt, a red school shirt (Webber Academy), grey school pants (Webber Academy), blue jeans, and a UV reflectant bathing suit. Responding VariablesThe responding variables in my experiment are how fast the UV beads change color (beads that change colour with exposure to UV light) and how much UV light makes its way through each of the fabric samples.What is UV light?UV light (ultraviolet light) is a high frequency type of light that is radiated from the sun. It is invisible to the human eye and is a part of the electromagnetic spectrum.
The spectrum is separated into seven sections that make up the different wavelengths of light. These sections include radio waves, microwaves, infrared (IR), visible light, ultraviolet (UV), X-rays and gamma-rays. Electromagnetic radiation comes from the sun and is transmitted in waves, which are measured as and wavelengths. Overexposure to UV light can result in skin cancer (burns to the skin), destroyed cells, damage to eyes, and many other problems. It destroys cells by damaging their DNA and causing a reaction between two molecules of thymine. Thymine is one of the bases that make up DNA. When the cellular process is disrupted, cells cannot continue to function normally, therefore, they are damaged. UV light consists of three types: UVA, (near UV), UVB, (middle UV), and UVC, (far UV).
The shorter the wavelength, the more damage it can do to someone, from sunburns to skin cancer. UVA has a longer wavelength (315–400 nm), thus doing less damage, but it can still be harmful. UVB, also referred to as the “middle UV”, is a wavelength that is found somewhere between UVA light and UVC light as about 280–315 nm. UVC, the most harmful type of UV light, has a short wavelength of 180–280 nm. UVC is blocked out by the Earth’s ozone layer, therefore, it does not reach the Earth’s surface.The Ozone Layer Earth’s atmosphere consists of many layers.
Ozone (O3) is a colourless gas that contains three atoms in its molecule. The Ozone layer blocks out almost all radiation of wavelengths less than 290 nanometres and prevents them from reaching the Earth’s surface and injuring/killing many living things. The lowest layer in the Earth’s atmosphere, referred to as the troposphere, travels up to about 10 km. in altitude. All human activity occurs in the troposphere layer of the Earth’s atmosphere. The stratosphere layer is right above troposphere. It continues up to about 10 km to 50 km in altitude.
Temperatures begin to increase at higher altitudes due to the ozone absorbing ultraviolet radiation. How do UV Beads Work? UV beads often, if not, always contain a special pigment/chemical that changes colour when exposed to UV light. UV beads can change colour back and forth between white and their full colour about 50 000 times, before they no longer respond to to any UV light. A chemical reaction occurs when the beads are struck by the UV light that causes them to change colour.