Unit of measure for emission values Valid None Data Dictionary Vocabularies Eionet Data Dictionary kilogram per year Mass flow rate. Conversion to SI unit: 1 kg/s = 31536000 t/a. Used for loads or emissions of hazardous substances. Valid Data Dictionary Vocabularies Eionet Data Dictionary Unit of measure for emission values tonne per year Mass flow rate. Conversion to SI unit: 1 kg/s = 31536 t/a. Used for loads or emissions of nutrients of oxygen consuming substances. Valid Data Dictionary Vocabularies Eionet Data Dictionary Unit of measure for emission values