safety-in-academic-chemistry-laboratories-students

Permissible exposure limit pel this number is the

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Unformatted text preview: as milligrams of material per liter (mg/L) of air for dusts and mists expected to kill 50% of a test animal population within a specified time by inhalation. Permissible exposure limit (PEL). This number is the concentration of a hazardous chemical in the air expressed in units of ppm or mg/m3. This number is established by OSHA after consultation with physicians, scientists, labor unions, and chemical manufacturers as the maximum concentration in the breathing air that can be inhaled without harm by an adult worker for 8 hours a day, 40 hours a week, during his or her working lifetime‚ÄĒprovided that the worker is a person of average health. Physical/chemical properties. This section usually includes some of the following items: Boiling point. The value may be expressed either in degrees Celsius or Fahrenheit, usually at atmospheric pressure but, if so stated, may be at reduced pressure. Melting point. Either in degrees Celsius or Fahrenheit. Vapor pressure. Usually in torr at a specified temperature or at approximately room temperature if the temperature is not specified. Specific gravity. Density with respect to water at a specified temperature or, if not specified, understood to be approximately room temperature. Solubility. The value given is usually the approximate solubility in water and is at room temperature unless stated otherwise. Appearance and odor. Liquid, solid, or gas (at room temperature); color, crystalline, or amorphous; odoriferous or not; and other characteristics. Evaporation rate. Usually relative to n-butyl acetate or other named volatile substance. Precautions for spills and cleanup. This section describes the procedures for proper cleanup of a spill or release. An appropriate waste disposal method, including whether the material can be put in a landfill or an EPA-approved disposal facility, is sometimes described in this part. 6Flammable limits are determined by measurements in a laboratory under controlled conditions. Generally, the conditions under which these values are determined are not the same as the conditions existing in the laboratory where the flammable liquid is being used. Consequently, the...
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This document was uploaded on 02/27/2014 for the course PHYS 1B at UCSD.

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