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Authorized Protective Eyewear List
The Authorized Protective Eyewear List (APEL) is a list of protective eyewear tested and approved by the U.S. Military for use by its soldiers. The APEL includes spectacles and goggles optimized for different situations. History The APEL was created in 2006 because statistics showed that about 10% of battlefield injuries at that time included eye injuries. The APEL is updated periodically; it usually contains more than a dozen types of non-prescription and prescription spectacles and goggles for different duty situations and soldier preferences. In 2010, the APEL was placed under the oversight of the Military Combat Eyewear Protection (MCEP) program under the office of PEO Soldier. Styles The APEL also includes different styles to accommodate soldier preferences, with the goal of increasing the use of eye protection. Approved protective eyewear includes both military standard and commercial styles. Soldiers serve in different situations with different types of risk for eye injury, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eye Protection
Eye protection is protective gear for the eyes, and sometimes face, designed to reduce the risk of injury. Examples of risks requiring eye protection can include: impact from particles or debris, light or radiation, wind blast, heat, sea spray or impact from some type of ball or puck used in sports. Eye protection are typically separated into categories based on the style of eye wear and the hazard they are designed to reduce. There categories include: Spectacles with side protection; Goggles; Welding helmet; Welding Hand Shields; Non-Rigid Helmets (hoods); Face shield; and Respirator Face pieces. Styles Spectacles Safety glasses or spectacles, although often used as a catch-all term for all types of eye protection, specifically revers to protective equipment that closely resembles common eye wear. To meet most national standards, spectacles must include side shields to reduce the ability of debris to get behind the lenses from the side. Safety glasses can often mount i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Statistics
Statistics (from German language, German: ''wikt:Statistik#German, Statistik'', "description of a State (polity), state, a country") is the discipline that concerns the collection, organization, analysis, interpretation, and presentation of data. In applying statistics to a scientific, industrial, or social problem, it is conventional to begin with a statistical population or a statistical model to be studied. Populations can be diverse groups of people or objects such as "all people living in a country" or "every atom composing a crystal". Statistics deals with every aspect of data, including the planning of data collection in terms of the design of statistical survey, surveys and experimental design, experiments.Dodge, Y. (2006) ''The Oxford Dictionary of Statistical Terms'', Oxford University Press. When census data cannot be collected, statisticians collect data by developing specific experiment designs and survey sample (statistics), samples. Representative sampling as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spectacles
Glasses, also known as eyeglasses or spectacles, are vision eyewear, with lenses (clear or tinted) mounted in a frame that holds them in front of a person's eyes, typically utilizing a bridge over the nose and hinged arms (known as temples or temple pieces) that rest over the ears. Glasses are typically used for vision correction, such as with reading glasses and glasses used for nearsightedness; however, without the specialized lenses, they are sometimes used for cosmetic purposes. Safety glasses provide eye protection against flying debris for construction workers or lab technicians; these glasses may have protection for the sides of the eyes as well as in the lenses. Some types of safety glasses are used to protect against visible and near-visible light or radiation. Glasses are worn for eye protection in some sports, such as squash. Glasses wearers may use a strap to prevent the glasses from falling off. Wearers of glasses that are used only part of the time may hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goggles
Goggles, or safety glasses, are forms of protective eyewear that usually enclose or protect the area surrounding the eye in order to prevent particulates, water or chemicals from striking the eyes. They are used in chemistry laboratories and in woodworking. They are often used in snow sports as well, and in swimming. Goggles are often worn when using power tools such as drills or chainsaws to prevent flying particles from damaging the eyes. Many types of goggles are available as prescription goggles for those with vision problems. History The Inuit and Yupik peoples carved snow goggles from the antlers of caribou, wood, and shell to help prevent snow blindness. The goggles were curved to fit the user's face and had a large groove cut in the back to allow for the nose. A long thin slit was cut through the goggles to allow in a small amount of light, diminishing subsequent ultraviolet rays. The goggles were held to the head by a cord made of caribou sinew. In the early 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PEO Soldier
Program Executive Office Soldier is a US Army organization that is responsible for rapid prototyping, procurement, and fielding of equipment for its soldiers. Development areas Project Manager Soldier Protection and Individual Equipment (PM SPIE) develops and fields advanced Soldier protection products, comfortable uniforms to enhance mission effectiveness, and improved parachute systems. *Product Manager Soldier Protective Equipment (PdM SPE) develops and fields force protection equipment that defeats ballistic and fragmentation threats in theater. PM SPE provides body armor, helmets, and other gear that reduce the threat of serious injury. *Product Manager Soldier Clothing and Individual Equipment (PdM SCIE) supports soldiers in operational environments by providing safe, durable, and operationally effective individual and unit equipment. PM SCIE enhances survivability through technologically advanced tactical and environmental protective clothing, individual chemical protectiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ballistics
Ballistics is the field of mechanics concerned with the launching, flight behaviour and impact effects of projectiles, especially ranged weapon munitions such as bullets, unguided bombs, rockets or the like; the science or art of designing and accelerating projectiles so as to achieve a desired performance. A ballistic body is a free-moving body with momentum which can be subject to forces such as the forces exerted by pressurized gases from a gun barrel or a propelling nozzle, normal force by rifling, and gravity and air drag during flight. A ballistic missile is a missile that is guided only during the relatively brief initial phase of powered flight and the trajectory is subsequently governed by the laws of classical mechanics; in contrast to (for example) a cruise missile which is aerodynamically guided in powered flight like a fixed-wing aircraft. History and prehistory The earliest known ballistic projectiles were stones and spears, and the throwing stick. The oldes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prescription Lenses
An eyeglass prescription is an order written by an eyewear prescriber, such as an optometrist, that specifies the value of all parameters the prescriber has deemed necessary to construct and/or dispense corrective lenses appropriate for a patient. If an eye examination indicates that corrective lenses are appropriate, the prescriber generally provides the patient with an eyewear prescription at the conclusion of the exam. The parameters specified on spectacle prescriptions vary, but typically include the patient's name, power of the lenses, any prism to be included, the pupillary distance, expiration date, and the prescriber's signature. The prescription is typically determined during a refraction, using a phoropter and asking the patient which of two lenses is better, or by automated refractor, or through the technique of retinoscopy. A dispensing optician will take a prescription written by an optometrist and order and/or assemble the frames and lenses to then be dispensed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Night Vision Device
A night-vision device (NVD), also known as a night optical/observation device (NOD), night-vision goggle (NVG), is an optoelectronic device that allows visualization of images in low levels of light, improving the user's night vision. The device enhances ambient visible light and converts near-infrared light into visible light which can be seen by the user; this is known as I2 ( image intensification). By comparison, viewing of infrared thermal radiation is referred to as thermal imaging and operates in a different section of the infrared spectrum. A night vision device usually consists of an image intensifier tube, a protective housing, and may have some type of mounting system. Many NVDs also include a protective sacrificial lens, mounted over the front lens (ie. objective lens) on NVDs to protect the latter from damage by environmental hazards and some can incorporate [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ballistic Eye Wear
Ballistic eyewear is a form of glasses or goggles that protect from small projectiles and fragments. For the U.S. military, choices are listed on the Authorized Protective Eyewear List (APEL). Ballistic eyewear including examples that meet APEL requirements are commercially available for anyone who wishes to buy it. The history of protective eyewear goes back to 1880 and extends through to World War I and the present. There are three standards that are currently used to test the effectiveness of ballistic eyewear. These include a U.S. civilian standard (ANSI Z87.1 – 2010), a U.S. military standard (MIL-PRF-31013), and a European standard (EN 166, 169, 170 and 172). Types Safety glasses, sunglasses and goggles that claim to meet ballistic safety standards are widely available. Some can accommodate prescription lenses. Although not required, it is recommended that all eyewear meet ANSI Z87.1, but for ballistic protective eyewear it is required that it meets military standards fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Droplet
A drop or droplet is a small column of liquid, bounded completely or almost completely by free surfaces. A drop may form when liquid accumulates at the lower end of a tube or other surface boundary, producing a hanging drop called a pendant drop. Drops may also be formed by the condensation of a vapor or by atomization of a larger mass of solid. Water vapor will condense into droplets depending on the temperature. The temperature at which droplets form is called the dew point. Surface tension Liquid forms drops because it exhibits surface tension. A simple way to form a drop is to allow liquid to flow slowly from the lower end of a vertical tube of small diameter. The surface tension of the liquid causes the liquid to hang from the tube, forming a pendant. When the drop exceeds a certain size it is no longer stable and detaches itself. The falling liquid is also a drop held together by surface tension. Viscosity and pitch drop experiments Some substances that appear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fine Dust
Particulates – also known as atmospheric aerosol particles, atmospheric particulate matter, particulate matter (PM) or suspended particulate matter (SPM) – are microscopic particles of solid or liquid matter suspended in the air. The term ''aerosol'' commonly refers to the particulate/air mixture, as opposed to the particulate matter alone. Sources of particulate matter can be natural or anthropogenic. They have impacts on climate and precipitation that adversely affect human health, in ways additional to direct inhalation. Types of atmospheric particles include suspended particulate matter; thoracic and respirable particles; inhalable coarse particles, designated PM, which are coarse particles with a diameter of 10 micrometers (μm) or less; fine particles, designated PM, with a diameter of 2.5 μm or less; ultrafine particles, with a diameter of 100 nm or less; and soot. The IARC and WHO designate airborne particulates as a Group 1 carcinogen. Particula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mist
Mist is a phenomenon caused by small droplets of water suspended in the cold air, usually by condensation. Physically, it is an example of a dispersion. It is most commonly seen where water vapor in warm, moist air meets sudden cooling, such as in exhaled air in the winter, or when throwing water onto the hot stove of a sauna. It can be created artificially with aerosol canisters if the humidity and temperature conditions are right. It can also occur as part of natural weather, when humid air cools rapidly, notably when the air comes into contact with surfaces that are much cooler than the air (e.g. mountains). The formation of mist, as of other suspensions, is greatly aided by the presence of nucleation sites on which the suspended water phase can congeal. Thus even such unusual sources of nucleation as small particulates from volcanic eruptions, releases of strongly polar gases, and even the magnetospheric ions associated with polar lights can in right conditions trigger ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
