Keywords:  mists, fumes, dusts, cubic, gases
mg/m3 A measure of concentration, often used to express PELs and TLVs.
A way of expressing the concentration of dusts, gases, aerosols, or mists in the air. A milligram (mg) is a unit of weight in the metric system–1,000 milligrams equals 1 gram. A cubic meter (m3) is a volume measurement in the metric system–1 m3 is about 35.3 cubic feet or 1.3 cubic yards.
A unit that expresses the concentration of a substance in air. A milligram per cubic meter is one one-thousandth of a gram per cubic meter of air. The milligram (1,000 micrograms) is used with higher concentrations.