milligrams per cubic meter; one unit of measurement for chemicals in air (compare to "ppm").
milligram per cubic meter
milligram per cubic metre
Milligrams of material per cubic meter (of air or water).
Milligrams per cubic meter is a unit for expressing concentrations of dusts, gases, or mists in air.
Milligrams of contaminant per cubic meter of air, a mass to volume ratio
(milligrams per meter cubed) A measure of concentration (weight by volume).
mg/m3 means milligrams of a chemical in a cubic meter of air. It is a measure of concentration (weight/volume).