Equilibrium dust content

Equilibrium dust content The amount of dust held on a clean filter cloth, which after a period of time remains approximately constant. 

Clean and remove electrostatic charges from the solution tubes by wiping them with a wet towel and drying them with a clean lint-free cloth (without tubbing). Place the tubes in the wire-screen tray, cover them with a cloth to protect them from dust, and allow them to stand near die balance for at least 30 mins to attain equilibrium with the moisture content of the air... 

There is no known biochemical reaction in organisms that applies Hg as an essential element. Mercury is the only metal which is a liquid at ordinary temperatures. The boiling point of this metal is 357 °C. This temperature is relatively low for metals and its vapor pressure is significant even at room temperature. The threshold limit value (TLV) of elemental mercury is 0.05 mg/m- a value that is less than the equilibrium vapor pressure at ambient temperatures. However, in the mercury miners in Sicily, where the mercury occurs in shales, the miners are exposed to elemental mercury vapor, which content in the air may reach toxic levels of about 5 mg/nr Another source of exposure in mines is the mercury-containing dust. 

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