However, UVC is completely absorbed by. So what is the most dangerous type of UV radiation? There is no good answer to this question, although it is frequently asked. On the one hand, UVC radiation is the most dangerous because it is the highest-energy part of the UV spectrum. However, UVC rays are completely absorbed by the Earth's atmosphere, so they pose no risk to most people.
Only a risk for people exposed to artificial UVC sources (see below). The. gov means it's official, federal government websites often end in. Gov or.
Thousand. Before sharing sensitive information, make sure you're on a federal government site. All radiation is a form of energy, most of which is invisible to the human eye. UV radiation is just one form of radiation and is measured on a scientific scale called the electromagnetic spectrum (EM).
UV radiation is just one type of electromagnetic energy you might be familiar with. The radio waves that transmit sound from a radio station tower to the stereo or between mobile phones; microwaves, such as those that heat food in a microwave oven; the visible light emitted by house lights; and X-rays, such as those used in hospital X-ray machines to capture images of bones inside the body, are all forms of electromagnetic energy. UV radiation is the part of the electromagnetic spectrum between X-rays and visible light. Learn more about UV radiation Electromagnetic radiation is all around us, although we can only see part of it.
All electromagnetic radiation (also called electromagnetic energy) is made up of tiny packets of energy or “particles”, called photons, that travel in a wave-like pattern and move at the speed of light. The electromagnetic spectrum is divided into categories defined by a range of numbers. These ranges describe the level of activity, or the energy of the photons, and the size of the wavelength in each category. For example, at the bottom of the spectrum, radio waves have photons with low energies, so their wavelengths are long with widely separated peaks.
Microwave photons have higher energies, followed by infrared waves, UV rays, and X-rays. At the top of the spectrum, gamma-rays have photons with very high energies and short wavelengths with peaks very close to each other. Learn more about the electromagnetic spectrum UVA rays have the longest wavelengths, followed by UVB and UVC rays, which have the shortest wavelengths. While UVA and UVB rays are transmitted through the atmosphere, all UVC and some UVB rays are absorbed by the Earth's ozone layer.
Therefore, most of the UV rays you come into contact with are UVA, with a small amount of UVB. Like all forms of light in the electromagnetic spectrum, UV radiation is classified by wavelength. The wavelength describes the distance between the peaks of a wave series. UVC radiation from the Sun does not reach the Earth's surface because it is blocked by the ozone layer in the atmosphere.
Therefore, the only way that humans can be exposed to UVC radiation is through an artificial source, such as a lamp or laser. If you have suffered an injury related to using a UVC lamp, we recommend that you report it to the FDA. In addition, some UVC lamps generate ozone, which could cause irritation to the respiratory tract (i.e., nose, throat, and lungs), especially in people with respiratory sensitivities, such as asthma or allergies. Exposure to high levels of ozone gas can also worsen chronic respiratory diseases, such as asthma, or increase vulnerability to respiratory infections.
Both UVA and UVB rays can damage the skin. Sunburn is a sign of short-term overexposure, while premature aging and skin cancer are side effects of long-term exposure to UV rays. Certain oral and topical medications, such as antibiotics, birth control pills and benzoyl peroxide products, as well as some cosmetics, can increase skin and eye sensitivity to UV rays on all skin types. Check the label and ask your doctor for more information.
Learn more about the risks of tanning Learn about the known health effects of UV rays Learn more about the health effects of overexposure to the sun Learn more about the types of UV radiation Phototherapy involves exposing the patient to a carefully controlled dose of UV radiation on a regular basis. In some cases, effective therapy requires that the patient's skin be first treated with a prescription medication, ointment, or bath that increases its sensitivity to UV rays. While this type of therapy does not eliminate the negative side effects of UV exposure, the treatment is carefully monitored by a doctor to ensure that the benefits outweigh the risks. UV rays are strongest in areas close to the equator.
Because the sun is directly above the equator, UV rays only travel a short distance through the atmosphere to reach these areas. UV radiation is also the strongest near the equator because the ozone in these areas is naturally thinner, so there is less to absorb UV radiation. UV exposure is lower in areas farther from the equator because the sun is farther away. Exposure also decreases because UV rays must travel a greater distance through ozone-rich parts of the atmosphere to reach the Earth's surface.
UV exposure is also greater in areas of snow, sand, pavement and water because of the reflective properties of these surfaces. The angle of the Sun with respect to the Earth varies by season. During the summer months, the sun is at a more direct angle, resulting in a greater amount of UV radiation. UV rays are most intense at noon, when the sun is at its highest point in the sky, and UV rays have the shortest distance to travel through the atmosphere.
Especially in the hot summer months, it's a good idea to stay home during peak sun hours, from 10 to. m. At 4 p. m.
Many people believe that you can't get sunburned on a cloudy day - this is simply not so. Even under a layer of clouds, it is possible to damage the skin and eyes and cause long-term damage. It's important to protect yourself with sunscreen, even on cloudy days. Learn more about the environmental factors of UV exposure The Ultraviolet Index (UVI) is a rating scale, with numbers from 1 to 11, that indicates the amount of UV rays that damage the skin and that reach the Earth's surface during the day.
The daily UVI forecasts the amount of UV that will reach your area at noon, when the sun normally reaches its highest point in the sky. The higher the number of UVIs, the more intense the UV rays you will be exposed to. The Environmental Protection Agency (EPA) offers UVI forecasts by zip code on its UV index page. Many UVI illustrations use a color system to designate the levels of UV exposure for a particular area of the map.
The World Health Organization (WHO) has developed an internationally recognized color system that corresponds to UVI levels. The eyes are very sensitive to UV radiation. Prolonged direct exposure to UV-B and UV-C light can cause serious effects, such as conjunctivitis and photokeratitis. Conjunctivitis is an inflammation of the membranes that line the inside of the eyelids and cover the cornea.
Photokeratitis is manifested as an aversion to bright light. The severity of these conditions depends on the duration, intensity, and wavelength. Symptoms may appear 6 to 12 hours after exposure and may disappear after 24 to 36 hours without permanent damage. .
