Lampwork Glasses

About

Lampwork (also called lampworking, flameworking or torchworking) is a type of glasswork in which the primary heat source for working the glass is a torch flame. When the flame is applied to glass, a small amount of elemental sodium sublimates from the surface of the glass and is burned in the flame. This burning causes an intense bright yellow light called a "sodium flare". The use of special-purpose lampwork glasses is essential to filter out the yellow light, enabling the glassworker to see the glass material as it is being worked. Soft glass becomes pliable at approximately 560 degrees C (1000 degrees F), while borosilicate glass (also called "hard glass") has a softening point as high as 820 degrees C (approx. 1500 degrees F). Due to the high temperatures that glass is heated to, the exposure to infrared light (heat) is also a concern. Infrared light may damage the eyes and cause a "glassblower's cataract". Furthermore, burning hydrocarbons present in the torch flame emit ultraviolet (UV) and high-energy blue light, which may also cause injury to the eyes and retina over time. Due to the optical radiation hazards, when practicing lampwork, a minimum Shade #3 lens (blocking at least 90% of average infrared light) should be used at all times. However, many didymium glasses sold as lampwork glasses have unrated lenses that do not meet the strict ANSI Z87.1 standards for a Shade #3 lens.