Bismuth regulation

Leadless Glaze. In the UK this is defined in the Potteries etc (Modifications) Regulations 1990 (S.I. 305) . A glaze which does not contain more than 1% of its dry weight of a lead compound calculated as PbO. Under current environmental pressures to reduce the use of lead, bismuth glaze and colour flux systems are being actively studied. Lean Clay. A clay of low plasticity the adjective lean is also applied to a body of low plasticity. 

The CHTR incorporates a passive power regulation system (PPRS) [XXIX-5]. This system includes a gas header filled with helium gas at moderate pressure. The header is attached to a niobium driver tube, which contains lead-bismuth eutectic alloy as driven liquid. The driver tube is housed within a control tube that contains an annular control rod made of boron carbide with niobium cladding. The annular space between the driver and control tube contains lead-bismuth eutectic, on which the control rod floats. The space above the liquid... 

Lead and other heavy metals such as silver, copper, cadmium, lead and bismuth have been known to have toxic effects on humans and our environment since ancient time [3]. These metals have become mainstays in the electronic world in which we live. As a result, human and environmental exposure to these metals has increased significantly over the past several decades, leading to significant health concern and environmental degradation. Lead and other metals enter the environment and the human body through several routes, which environmental and health regulations seek to reduce or eliminate. 

Bismuth currently sees little regulation from any governmental authority worldwide. This is due to its perceived low toxicity and generally low industrial use. 

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