Ka'idojin fitar da hayaki na EURO wani tsari ne na ka'idoji da Tarayyar Turai ta kafa domin takaita adadin gurbatacciyar iska da motoci ke fitarwa. Kowane ma'auni na EURO yana saita takamaiman iyaka don gurɓataccen abu, kamar nitrogen oxides (NOx), ƙwayoyin cuta (PM), carbon monoxide (CO), da hydrocarbons (HC). Mafi girman lambar EURO, mafi tsananin iyakoki. Anan ga manyan bambance-bambance tsakanin EURO 6, 5, 4, 3, da 2:
EURO 2: An gabatar da ka'idojin EURO 2 a cikin 1996. Da farko sun fi mayar da hankali kan rage hayakin carbon monoxide (CO) da hydrocarbon (HC) daga injunan man fetur (gasoline) da gurɓataccen abu (PM) daga injunan diesel.
EURO 3: Ka'idojin EURO 3 sun fara aiki a shekara ta 2000. Sun kara tsaurara iyakokin CO, HC, da PM kuma sun gabatar da takunkumin farko kan hayakin nitrogen oxides (NOx) na duka injunan man fetur da dizal.
EURO 4: An aiwatar da ma'auni na EURO 4 a cikin 2005. Sun rage yawan hayakin NOx daga injunan diesel, da nufin magance matsalolin gurɓacewar iska a cikin birane.
EURO 5: An gabatar da ma'auni na EURO 5 a cikin 2009. Sun kuma rage iyakokin NOx da PM daga injunan diesel. Bugu da ƙari, ƙa'idodin EURO 5 sun sanya ƙayyadaddun ƙayyadaddun ƙayyadaddun abubuwa (PM) hayaƙin injin mai.
EURO 6: An aiwatar da ma'auni na EURO 6 a cikin matakai biyu: EURO 6a a cikin 2014 da EURO 6b a cikin 2017. Waɗannan ƙa'idodin sun kawo mafi girman raguwar hayaki zuwa yau. EURO 6 ya gabatar da iyakataccen iyaka akan iskar nitrogen oxides (NOx) daga duka injunan man fetur da dizal, tare da ƙarin raguwar fitar da ƙura (PM) daga injin dizal.
EURO 6d-TEMP da EURO 6d: Waɗannan ƙarin kari ne ga ma'auni na EURO 6 waɗanda ke saita ko da ƙananan iyakoki. An gabatar da EURO 6d-TEMP a cikin 2019, da kuma EURO 6d a cikin 2020. Waɗannan ƙa'idodin suna ƙara rage fitar da NOx na gaske a duniya kuma sun haɗa da ƙarin tsauraran hanyoyin gwaji don tabbatar da bin ƙa'idodin tuƙi daban-daban.
EURO 6d-TEMP da EURO 6d sun zama mafi inganci na yau da kullun da ƙa'idodi masu tsauri, suna mai da hankali kan rage gurɓataccen gurɓataccen abu da haɓaka motoci masu tsabta da muhalli. Yana da mahimmanci a lura cewa kowane ma'auni na EURO ya shafi nau'ikan motoci daban-daban (misali, motoci, manyan motoci, bas) kuma yana iya samun kwanakin aiwatarwa daban-daban don sabbin ƙirar mota. Matsayin EURO yana ci gaba da haɓakawa don magance damuwa da girma game da ingancin iska da tasirin muhalli.