Silver the periodic table) is useful in nuclear reactors because of its high thermal neutron capture cross-section, good conduction of heat, mechanical stability, and resistance to corrosion in hot water. The word "silver" appears in Anglo-Saxon in various spellings, such as "seolfor" and "siolfor". A similar form is seen throughout the Germanic languages (compare Old High German "silabar" and "silbir"). The chemical symbol Ag is from the Latin word for "silver", "argentum" (compare Ancient Greek ἄργυρος, "árgyros"), from the Proto-Indo-European root *"h₂erǵ-" (formerly reconstructed as "*arǵ-"), meaning "white" or "shining": this was the usual Proto-Indo-European word for the metal, whose reflexes
Hazard symbol carry a significant health risk (biohazards), including viral samples and used hypodermic needles (see sharps waste). The biohazard symbol was developed by the Dow Chemical Company in 1966 for their containment products. According to Charles Baldwin, an environmental-health engineer who contributed to its development: "We wanted something that was memorable but meaningless, so we could educate people as to what it means." In an article in "Science" in 1967, the symbol was presented as the new standard for all biological hazards ("biohazards"). The article explained that over 40 symbols were drawn up by Dow artists, and all of the symbols