Goggles or safety glasses are forms of protective eyewear that usually enclose or protect the eye area 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 Eskimos carved goggles from caribou antler, as well as 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.

Image:Inuit Goggles.jpg|Traditional Inuit goggles used to combat snow blindness Image:Blowtorching goggles and helmet.jpg|Blowtorching goggles and safety helmet Image:AE.jpg|Aviation goggles as worn by Amelia Earhart Image:Swimming goggles.JPG|Swimming goggles

Types

The requirements for goggles varies depending on the use. Some examples:

• Cold weather: Most modern cold-weather goggles have two layers of lens to prevent the interior from becoming "foggy". With only a single lens, the interior water vapor condenses onto the lens because the lens is colder than the vapor, although anti-fog agents can be used. The reasoning behind dual layer lens is that the inner lens will be warm while the outer lens will be cold. As long as the temperature of the inner lens is close to that of the interior water vapor, the vapor should not condense. However, if water vapor gets between the layers of the lens, condensation can occur between the lenses and is almost impossible to get rid of; thus, properly constructed and maintained dual-layer lenses should be air-tight to prevent water vapor from getting in between the lenses.
• Swimming: Must be watertight to prevent water, such as salt water when swimming in the ocean, or chlorinated water when swimming in a pool, from irritating the eyes or blurring vision. Allows swimmers to see clearly underwater. They will not be usable more than a few feet underwater, because the water pressure will press them tightly against the face. Examples of these include the Swedish goggles.
• Power tools: Must be made of an unbreakable material that prevents chunks of metal, wood, plastic, concrete, and so on from hitting or piercing the eye. Usually has some sort of ventilation to prevent sweat from building up inside the goggles and fogging the surface.
• Blowtorch goggles: These protect the eyes from glare and flying sparks and hot metal splashes while using or near as blowtorch. They are not dark enough for arc welding.
• Motorcycle riding and other open-air activities: Prevents insects, dust, and so on from hitting the eyes.
• Laboratory and research: Combines impact resistance with side shields to prevent chemical splashes reaching the eyes. May also include laser protection which would be covered by EN 207 (Europe) and ANSI Z 136 (United States). Examples of these include red adaptation goggles.
• Racquetball: Protect the eyes from racquets swinging in an enclosed area and from impact from hard rubber ball.
• Winter sports: Protect the eyes from glare and from icy particles flying up from the ground.
• Astronomy and meteorology: dark adaptor goggles are used before going outside at night, in order to help the eyes adapt to the dark.
• Basketball: Several NBA players have worn goggles during play, including Kareem Abdul-Jabbar, James Worthy, Horace Grant and Kurt Rambis; they prevent a fellow player from scratching or hitting the eyes when trying to grab the basketball.
• Aviation: In open cockpit aircraft, similar to biplanes, aviators, such as Amelia Earhart and Charles Kingsford Smith, would wear goggles to help protect from the wind and are still in use today. Examples of these include the AN-6530 goggles.
• Virtual reality: A virtual reality headset, sometimes called "goggles", is a wrap-around visual interface to display computer output. Commonly the computer display information is presented as a three-dimensional representation of real-world environments.