Effects of electromagnetic waves (ALARA)

• Radiation exists all around us from both natural and man-made sources, coming in two forms: ionizing and non-ionizing radiation.
• Ionizing radiation is a form of energy that acts by removing electrons from atoms and molecules of materials that include air, water, and living tissues.
• Non-ionizing radiation is a form of low energy radiation that does not have enough energy to remove an electron from an atom or molecule.
• Most types of non-ionizing radiation have not been found to cause cancer.
• The dividing line between non-ionizing and ionizing radiation occurs in the ultraviolet part of the electromagnetic spectrum.
• Ultraviolet radiation comes from the sun, welding black lights, and UV lasers.
• Exposure time can be minimized by keeping voice calls short, especially when using hands-free.
• Radiation exists all around us from both natural and man-made sources and comes in ionizing and non-ionizing forms.
• Power and limit are also crucial factors in minimizing electromagnetic radiation hazards.
• Turning off wireless devices at night, such as cell phones, wireless phones, and computers, can help minimize exposure to electromagnetic radiation.
• Distance from a radiation source is a crucial factor in protecting oneself from its harmful effects.
• Using a wired-only printer and wired computer peripherals like a mouse and a keyboard can help minimize exposure to electromagnetic radiation.
• Gamma rays have the shortest wavelengths and highest frequencies, making them the most energetic type of electromagnetic wave.
• The alara principle includes time, distance, and shielding as key factors in minimizing electromagnetic radiation hazards.
• A Bluetooth headset delivers lower levels of microwave radiation than a cell phone but more than a wired headset.
• Using a wired headset emits less radiation than holding the phone to the head.
• The intensity of heat from a fireplace decreases as one moves away from it.
• The safest bet for cell phone use is in speakerphone mode with the phone a hand's length away.
• The sun emits UVA, UVB, and UVC rays, with UVC rays being absorbed by the ozone layer and never actually reaching the earth.
• Both UVA and UVB light are important for humans in the production of vitamin D, but overexposure to ultraviolet rays can be negative and can be immediate or delayed, causing sunburn, skin cancer, and cataracts.
• Visible light consists of seven colors: red, orange, yellow, green, blue, indigo, and violet.
• Overexposure to visible light can damage both the eyes and skin.
• Infrared is used in thermal scanners, remote controls, and night vision goggles, and the human eye can't see most of the infrared spectrum.
• About half of the total energy the sun gives off is in the form of infrared radiation, which we feel as heat.
• Exposure to electromagnetic fields in the radio frequency range can warm up exposed parts of the body because these absorb the radio wave and convert these into heat.
• X-rays, used in science, medicine, and industry, can cause mutations in our DNA and therefore might lead to cancer later in life.
• In radiation safety, distance refers to the distance from the radiation source, keeping your distance from the radiation source to avoid unnecessary exposure.
• Neutrons have a relatively high biological effectiveness and are roughly 10 times more dangerous at causing biological damage compared to gamma or better radiation of equivalent energy exposure.
• Time in radiation safety refers to the amount of time you spend near a radiation source, minimizing your time near a radiation source to only what it takes to get the job done.
• Neutron radiation consists of a free neutron, usually emitted as a result of spontaneous or induced nuclear fission, and can be effectively stopped if blocked by a hydrogen-rich material such as concrete or water.
• Shielding in radiation safety means using a barrier to block radiation, using high atomic number materials like lead or depleted uranium being the most effective form of shielding.
• People are exposed to natural radiation sources as well as man-made sources on a daily basis.
• Alpha particles, emitted from decay, lack the energy to penetrate even the outer layer of skin, making exposure to the outside of the body not a major concern.
• Gamma rays can penetrate just about anything, even bones, making them very dangerous as they can destroy living cells, produce gene mutations, and cause cancer.
• X-rays provide a low dose of radiation that is not believed to cause any immediate health problems.
• Neutrons are particularly damaging to soft tissues like the cornea of the eye.
• The guiding principle of radiation safety is ALARA, which stands for As Low As Reasonably Achievable, meaning that even if it is a small dose, if receiving that dose has no direct benefit, you should try to avoid it.
• Gamma radiation, unlike alpha or beta, consists of a photon of energy being emitted from an unstable nucleus, and can be stopped by a thick or dense enough layer of material with high atomic number materials such as lead or depleted uranium being the most effective form of shielding.
• Beta particles, emitted from decay, can penetrate skin a few centimeters, posing somewhat of an external health risk.
• Neutrons can either cause cells to change in their functionality or to completely stop replicating, causing damage to the body over time.