Micrograms per Cubic Metre (μg/m3) / Parts per Billion (PPB) Converter and Milligrams per Cubic Metre (mg/m3) / Parts per Million (PPM) Converter

The following calculators allow for the conversion of concentrations for a variety of pollutants between micrograms per cubic metre (µgm-3) and parts per billion (ppb), and between milligrams per cubic metre (mgm-3) and parts per million (ppm). A concentration in ppb (by volume) is the volume of a gaseous compound per billion volumes of ambient air whereas a concentration in µgm-3 is the mass of a gaseous compound (in µg) per cubic metre of ambient air.

This tool allows the user to convert between ambient concentration units at measurement temperatures (to a reference temperature of 0 degrees Celsius). It is particularly useful for standardising measurements taken for environmental studies.

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Table of Common Gasses and Molecular Weights

For quick and easy reference, see the table below with a list of common gasses and their molecular weights. (Source: Interscan Corporation)

Compound Formula Molecular Weight (g/mol)
Ammonia NH3 17.031
Arsine AsH3 77.945
Benzene C6H6 78.114
Bromine Br2 159.808
Carbon disulfide CS2 76.143
Carbon monoxide CO 28.01
Carbon tetrachloride CCl4 153.822
Chlorine Cl2 70.905
Chlorine dioxide ClO2 67.452
Dimethyl sulfide (CH3)S 62.136
Ethylene C2H4 28.054
Ethylene oxide H2COCH2 44.053
Formaldehyde HCHO 30.026
Hydrazine H2NNH2 32.045
Hydrogen H2 2.016
Hydrogen bromide HBr 80.912
Hydrogen chloride HCl 36.461
Hydrogen cyanide HCN 27.026
Hydrogen peroxide H2O2 34.015
Hydrogen sulfide H2S 34.082
Methyl mercaptan CH3SH 48.109
Monomethyl hydrazine CH3NHNH2 46.072
Nitric oxide NO 30.006
Nitrogen dioxide NO2 46.006
Nitrogen tetroxide N2O4 92.011
Ozone O3 47.998
Peracetic acid CH3COOOH 76.051
Phosphine PH3 33.998
Propylene oxide CH3CHOCH2 58.08
Silane SiH4 32.117
Sulfur dioxide SO2 64.065
Sulfuryl fluoride SO2F2 102.062
Unsymmetrical dimethyl hydrazine (CH3)2NNH2 60.0984

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Please note that this or any other calculators on the wkcgroup.com tools room are for information only. WKC Group has endeavoured to ensure that the information presented here is accurate and that the calculations are correct, but will not accept responsibility for any consequential damages, faults or human errors that may arise from the use of formulas, inventories and values.