Frequently Asked Questions

  • How do you convert ppb into µg/m3?

    Conversion factors from ppb to µg/m3 under standard temperature and pressure conditions are given in the Conversion Factors between ppb and µg/m3 and ppm and mgm-3 report (PDF 40.83 KB). For example, the conversion factor for NO from ppb to µg/m3 at 293K and 101.3 kPa is 1 ppb=1.248 µg/m3. There are air quality standards set for nitrogen dioxide and for total oxides of nitrogen (NOx=NO2+NO). EU regulations require that NOx concentrations are reported as NO2 equivalent i.e (NO+NO2)*1.91 rather than NO µg/m3+NO2 µg/m3.

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