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joanmon Apr 08, 2020 11:46 AM
Hello to everybody!
I would like to ask you a doubt that I have related to the measures of NO, NO2 and NOx expressed in micrograms/m3. As far as I'm concerned, NOx is a concept used to refer to a set of nitrogen oxides (NO, NO2, NO3... and so on). Then, when I consult NOx, NO and NO2 data -acquired from an automatic measurement analyzer- I see that the sum of NO and NO2 (expressed in ppb) equals to the concentration of NOx. However, if I transform these data in micrograms/m3, the sum of NO and NO2 never equals to NOx: it is always lower than NOx. Can anybody please give me an answer to this apparently incoherence? The thing is that I don't understand why in the second case the sum of NO and NO2 doesn't equals to NOx data.
Thanks in advance!
Replies (2)
EEA Apr 08, 2020 02:18 PM
Dear Joan M,

Thank you for contacting the European Environment Agency (EEA).
We acknowledge receipt of your message and will get back to you as soon as possible.

With kind regards,
EEA Enquiry Service
EEA Apr 14, 2020 08:55 AM
Dear Joan M.,

Would you please be so kind as to clarify which dataset(s) you are using and send us the link(s). This will help us deal with your enquiry in the most efficient manner.

Looking forward to hearing from you.

With kind regards,
EEA Enquiry Service