In what units are the measurements and when push notifications are set to come? All measurements are in PDK (max allowed volume). Push notifications are set to come at reaching 1x threshold and if getting worse, in geometric progression (2x, 4x, 8x etc)

How PDK is calculated? For each element, 1 PDK is (mg/m3):

E_CO:     3,
E_SO2:    0.25,
E_CH4:    50,
E_H2S:    0.168,
E_NH3:    0.3,
E_NO:     0.4,
E_NO2:    0.2,
E_OZ:     0.16,
E_PM10:   0.06,
E_PM25:   0.035,
E_C6H6:   0.15,
E_C10H8:  0.07,
E_C8H8:   0.5,
E_C7H8:   0.6,
E_C6H5OH: 0.05,
E_CH2O:   0.025,
E_RAD:    0.5,   // ╬╝Sv/h

What does the question mark on map mean? The station is registered, but there is no recent data for it. You still can add it to your watchlist, however if there is no data for this station for a longer period (several days) it will be deleted from the system completely.

What territories are covered? Most data sources are for Moscow (dust, industrial pollution, gases/vapor and radiation, there is also a midterm model of pollution based on this data for the last two days build hourly). Some Russian regions are covered. Also covered are Eastern Europe and some countries of Western Europe. US coverage is really sparse at the moment. If you have data sources with instrumental measurements for your city feel free to contact!

Can I buy the developer some beer, please?
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