Topics
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      Mercury Awareness and Safety
    • Atomic number 80
    • Also known as 
      quicksilver
    • Only metal that is liquid 
      at standard conditions 
      for temperature and 
      pressure
    • Only other element that 
      is liquid under these 
      conditions is bromine
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               Mercury (Hg)
    • Mercury occurs as 
      deposits; mostly as 
      cinnabar, known as 
      mercuric sulfide.
    • Cinnabar: Highly toxic  
      by ingestion or dust 
      inhalation
    • Elemental Hg can be 
      produced by heating 
      mercury-containing ores 
      and condensing the 
      vapor
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           Three (3) Classes of Hg
     • Mercury (Element) Hg
     • Organic (Methylmercury 
      & Phenylmercury)
     • Inorganic Compounds 
      known as Mercurial salts:
         • Mercury(I) chloride 
          (mercurous chloride)
         • a.k.a. Calomel
         • Mercury(II) chloride 
          (mercuric chloride)
            David Aldridge, his own work with permission
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        29 CFR 1910.1000, Subpart Z
      From Table Z-1: Limits for Air Contaminants 8-hr TWA
              Substance                   CAS No.              mg/m3  
      Mercury (aryl and inorganic)(as Hg) 7439-97-6    OSHA PEL: C 0.1
      Mercury (organo) alkyl 
      compounds (as Hg)                  7439-97-6    OSHA PEL: TWA 0.01
      Mercury (vapor)(as Hg)             7439-97-6    OSHA PEL: TWA 0.05
                                                                                [skin]
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