Posted By Bryn Maidment Lime dust , or quicklime, will react with the moisture in the mucous membranes (lungs, eyes, mouth etc.) or even with sweat on the skin. It forms an alkaline solution (calcium hydroxide or slaked lime) that will efectively 'burn' and cause discomfort,or in the worst case, breathing difficulty / pulmonary oedema (fluid on the lungs). I have read in previous threads about on-line chemical databases but can't think of any at present (it's Friday and my brain is already at home with an ice cold Fosters!!). Hopefully someone will post details. If you get a number for a company like Blue Circle who produce lime powder for the building sector give them a call and ask for a safety data sheet. Regards

Posted By Ken Taylor We have just had a new school built using lime mortar as it's part of a Grade 1 listed site in a consrvation area. Safety data for calcium hydroxide General Synonyms: slaked lime, calcium hydrate, biocalc, lime milk, lime water, milk of lime Molecular formula: Ca (OH)2 CAS No: 1305-62-0 EC No: 215-137-3 Physical data Appearance: white powder Melting point: 580 C Boiling point: Vapour density: 2.5 (air = 1) Vapour pressure: Density (g cm-3): 2.24 Flash point: Explosion limits: Autoignition temperature: Water solubility: slight Stability Stable. Incompatible with strong acids. Toxicology Skin, eye and respiratory irritant. Corrosive - causes burns. Typical TLV/TWA 5 mg m-3 Toxicity data ORL-RAT LD50 7340 mg kg-1 ORL-MUS LD50 7300 mg kg-1 Risk phrases R34 R36 R37 R38. Transport information Non-hazardous for air, sea and road freight. Personal protection Safety glasses. Minimize exposure to dust. Safety phrases S22 S26 S45. This information was last updated on December 15, 2000. We have tried to make it as accurate and useful as possible, but can take no responsibility for its use, misuse, or accuracy. We have not verified this information, and cannot guarantee that it is up-to-date.