Gallium highly reactive (rubidium and caesium) nor highly toxic (mercury) and can therefore be used in metal-in-glass high-temperature thermometers. It is also notable for having one of the largest liquid ranges for a metal, and for having (unlike mercury) a low vapor pressure at high temperatures. Gallium's boiling point, 2673 K, is more than eight times higher than its melting point on the absolute scale, the greatest ratio between melting point and boiling point of any element. Unlike mercury, liquid gallium metal wets glass and skin, along with most other materials (with the exceptions of quartz, graphite, and Teflon), making it
Substantial equivalence conference of officials and industry), although the term "substantial equivalence" was not used. Adopting the term, "substantial equivalence" was formulated as a food safety policy by the OECD, first described in their 1993 report, "Safety Evaluation of Foods Derived by Modern Biotechnology: Concepts and Principles. The term was borrowed from the FDA's 1976 substantial equivalence definition for new medical devices—under Premarket Notification 510(k), a new Class II device that is essentially similar to an existing device can be cleared for release without further testing. The underlying approach of comparing a new product or technique to an existing one has long