Silicon safety

In 1992, the FDA issued a moratorium on silicone-gel-filled implants, and restricted their use to reconstmction and clinical smdies. In 2000, they approved saline-filled implants. In 2003, the General and Plastic Surgery Devices (GPSD) Advisory Panel recommended reapproval of gel-filled implants, but the FDA decided to wait for more clinical evidence of safety. In late 2005, the Panel recommended conditional approval of Mentor s and Inamed s gel implants. In October 2006, Health Canada approved the use of sUicone-gel-filled implants, with a warning that no medical device is 100% safe. ... 

Hoffman D, Gong G, PinchukL, and Sisto D. Safety and intracardiac function of a silicone-pol)oirethane elastomer designed for vascular use. Clin Mater, 1993, 13, 95-110. 

Permatex Silicone Windshield Glass Sealer Material Safety Data Sheet, Permatex Industrial Corporation, http //hazard.com/msds/mf/perm/files/81730.TXT... 

S2C12, a by-product in the manufacture of carbon tetrachloride from carbon disulphide. Was used, dissolved in solvent naphtha, in the vulcanising of mbber by the cold cure process and the vapour cure process. The process was fraught with health and safety problems and has been superseded by low temperature accelerators and room temperature vulcanising (RTV) systems for silicone and polyurethane. 

One can see that for calcium, potassium, and silicon, biogeochemical turnover is within the limits of 10-30 kg/ha per year. The turnover for magnesium, phosphorus, manganese, sulfur, and aluminum is less than 10 kg/ha per year. These values are about 1 kg/ha per year for iron and sodium. These values can characterize the safety limits of exposure to the given species. 

Antimony (Sb), 3 41-56, 56. See also Group Ill-Sb system InAsSb alloy InSb photodiode detectors/arrays Lead-antimony alloys Low antimony lead alloys Stib- entries in babbitts, 24 797 catalyst poison, 5 257t chemical reactions, 3 42—44 in coal, 6 718 economic aspects, 3 47-48 effect of micro additions on silicon particles in Al-Si alloys, 2 311-312 effect on copper resistivity, 7 676t environmental concerns, 3 50 gallium compounds with, 12 360 health and safety factors, 3 51 in pewter, 24 798... 

High-energy irradiation, silicone network preparation via, 22 567 High energy ruminant feeds, 10 864-865 High enriched uranium (HEU), 17 526 Higher aliphatic alcohols aldol process, 2 41-43 analysis, 2 9-10, lOt chemical reactions, 2 4-6 economic aspects, 2 7-9 health and safety factor, 2 6 manufacture from fats and oils, 2 12-19 oxo process (odd-numbered alcohols), 2 1, 10, 36-41... 

Plasma etching, of silicon, 22 492 Plasma FPDs, 22 259 Plasma fractionation, 12 128-159 economic aspects of, 12 147-150 health, safety, and environmental factors related to, 12 153... 

Platinum deposition techniques, 79 157 Platinum dichloride, 79 655 Platinum-divinyltetramethyldisiloxane complex, in silicone network preparation, 22 563 Platinum films, 79 658 Platinum gauze catalyst, 77 180-181 Platinum-group metal compounds, 79 635-667 analysis of, 79 637 economic aspects of, 79 635-636 health and safety factors related to, 79 658... 

Thermoplastic elastomers (TPE), 9 565-566, 24 695-720 applications for, 24 709-717 based on block copolymers, 24 697t based on graft copolymers, ionomers, and structures with core-shell morphologies, 24 699 based on hard polymer/elastomer combinations, 24 699t based on silicone rubber blends, 24 700 commercial production of, 24 705-708 economic aspects of, 24 708-709 elastomer phase in, 24 703 glass-transition and crystal melting temperatures of, 24 702t hard phase in, 24 703-704 health and safety factors related to, 24 717-718... 

USA Silicone Environmental Health and Safety Council (SEHSC) Europe Centre Europeen des Silicones (CES) Japan Silicone Industry Association of Japan (SIAJ) Global Global Silicones Council (GSC). 

Figure 7 (a) Sartorius absorption model (b) Sartorius dissolution model, a, Plastic syringe b, timer c, safety lock d, cable connector e, silicon tubes f, silicon-O-rings g, metal filter h, polyacryl reaction vessel. 

It is very important to first consider the safety aspects of electrochemical experiments with silicon. The single most dangerous compound, which cannot be avoided in the electrochemistry of silicon, is hydrofluoric acid (HF). HF in its anhydrous form and in concentrated aqueous solutions is highly corrosive towards living tissue. Inhalation, ingestion or skin contact with HF are all extremely hazardous. 

The other chemicals mentioned in this book are less dangerous and safety goggles and rubber gloves, which should always be used, are usually sufficient protection. Elementary silicon is inert and shows no toxic effects. In this respect, silicon is different from many other semiconductors, which may contain poisonous compounds. However, sufficient eye protection is required while cleaving wafers, because of the risk of fragmentation. 

The HF tester is a commercial safety tool for sensing whether an unidentified liquid contains HF [2], It shows in an exemplary way how the electrochemical properties of a silicon electrode, namely its I-V curve in HF, can be applied for sensing. The ability to dissolve an anodic oxide layer formed on silicon electrodes in aqueous electrolytes under anodic bias is a unique property of HF. HF is therefore the only electrolyte in which considerable, steady-state anodic currents are observed, as shown schematically in Fig. 3.1. This effect has been exploited to realize a simple but effective safety sensor, which allows us to check within seconds if a liquid contains HF. This is useful for safety applications, because HF constitutes a major health hazard in semiconductor manufacturing, as discussed in Section 1.2. 

The electronic circuit of the safety sensor consists of a p-type silicon electrode, an LED, a resistor, two 3 V lithium batteries, and a platinum wire as a counter electrode, connected in series, as shown in the right part of Fig. 10.7. These components are assembled in a pen-like housing, optimized to measure even thin layers of liquid on a flat surface, as shown in the left part of Fig. 10.7. This configuration is advantageous if a puddle, observed for example under a wet bench or other equipment, is to be analyzed. 

Gluing is possible with adhesives based on epoxies, polyurethanes, silicones, cyanoacrylates and hot-melts. All precautions must be taken concerning health and safety according to local laws and regulations. 

Over the past several decades, there has been some concern over the potential hazards and safety of the cosmetic use of silicone body implants—breast implants, in particular. Several manufactures have been sued over the failure of the implants, and the federal government... 

Use Safety caps on medicine bottles White paint from lead oxide to titanium oxide breast implants from silicone oil to salt water... 

Diborane(6), B2H6. This spontaneously flammable gas is consumed primarily by the dectronics industry as a dopant in the production of silicon wafers for use in semiconductors. It is also used to produce amine boranes and the higher boron hydrides. Callery Chemical Co., a division of Mine Safety Appliances Co., and Voltaix, Inc., are the main U.S. producers of this substance. Several hundred thousand pounds were manufactured worldwide in 1990. 

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