uviol glass[′yü·vē‚ȯl ‚glas]
a glass that transmits ultraviolet radiation with λ < 400 nanometers, the biological region of the spectrum.
Uviol glasses are divided into three groups according to chemical composition: silicate glasses, which contain about 75 percent Si02; borosilicate glasses, which contain 68-80 percent Si02 and 12-14 percent B203; and phosphate glasses, which contain about 80 percent P203. A1203, CaO, MgO, and other compounds are also present. Quartz glass is also considered to be an uviol glass. Oxides of heavy metals, for example, Fe203, Cr203, and Ti02, and sulfides of heavy metals that absorb ultraviolet radiation must be absent.
Uviol glass is used in schools, day-care centers, medical facilities, and greenhouses; it also serves as the glass envelopes of germicidal and fluorescent lamps.