What Is a Safety Glass?
Safety glass refers to glasses that prevent dust, dirt, metal powder, and chemicals from entering the eyes.
They are often called “safety glasses” or “laboratory glasses.” They are used in a wide variety of locations, including laboratories and workrooms at universities and manufacturers, as well as outdoor workplaces where power tools and laser equipment are used.
Unlike ordinary eyeglasses, the type, construction, and materials used in safety goggles are strictly regulated by certain standards. There is also a type of safety eyewear known as protective goggles, which offers a higher level of protection compared to standard safety glasses.
Uses of Safety Glasses
Safety glasses are used in workplaces where people handle items that could be dangerous if they get into their eyes, and the standards stipulate the conditions for their use. In some cases, the use of safety goggles is required by each business site even in places where it is not required by law.
The method of use is the same as for ordinary eyeglasses, with the arms being placed over the ears to complete the wearing process. Currently, safety glasses designed to be worn over regular eyeglasses are also available in the market. To ensure the protection of one’s eyes, it is necessary to conduct a thorough inspection for any scratches or deformities before use.
Types of Safety Glasses
Safety glasses are used in a wide variety of workplaces, and there are many different types of safety glasses. Examples are as follows:
1. Overglass Type
Generally, safety glasses do not come in a lens-type version. For this reason, they are designed to be worn over eyeglasses for people who normally use glasses to correct their vision. The lenses are wider than those of ordinary safety glasses, and can fully cover the eyeglasses.
2. Heat-Resistant Type
In biological research fields, it is sometimes necessary to work in a sterilized environment. In such cases, all instruments used must be sterilized at high temperatures by autoclave or other means. General safety glasses cannot withstand sterilization at high temperatures (approx. 120°C) and become deformed. If you choose a heat-resistant type, you can sterilize them without any problem.
3. Anti-Scratch Type
Safety glasses are used not only in chemical and biological fields but also in grinding and cutting fields. Safety glasses with anti-scratch coating are used to ensure safety when working with metal fragments that may fly out. Other types of safety glasses are also available, such as small-sized ones for women and ones with anti-fog coating.
Structure of Safety Glasses
The difference between the construction of safety glasses and ordinary glasses is the shape of the lens portion. Ordinary spectacles have a gap around the lens, whereas safety glasses have a surrounding area around the eyes.
In situations where safety glasses are used, even a foreign object entering through a gap in the lens can cause a serious accident, so the structure is more protective.
Other Information on Safety Glasses
1. Standards for Safety Glasses
Safety glasses are more impact-resistant, abrasion-resistant, heat-resistant, and fog-resistant than ordinary glasses. They are constructed to withstand harsh environments, such as a laboratory surrounded by chemicals, or an outdoor work site where the environment is hot and subject to strong vibrations and impacts.
The standard for impact resistance is that the lens must not crack or split when an iron ball weighing 44g is dropped from a height of approximately 1.3m. The standard for heat resistance is that there must be no deformation at 55°C.
2. Material of Safety Glasses
Safety glasses are made of hard, impact-resistant plastic resin such as polycarbonate or acrylic resin for the lens portion. The frames are made of soft and easy-to-process materials such as polypropylene and soft polyvinyl chloride.
It is said that the lens portion can be used for 3 years and the frame portion for 5 years. Check daily for loose screws or hinges and for scratches or cracks on the lenses. Replace them with new ones as soon you notice any defects or you feel any discomfort.