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29. European emission standard
A European emission standard, commonly called a Euro standard, is a European vehicle classification based on limits for pollutants emitted by vehicles and their engines. Successive standards, such as Euro 4, Euro 5 and Euro 6, introduced progressively stricter requirements for pollutants such as nitrogen oxides, particulate matter, carbon monoxide and hydrocarbons.
A vehicle's Euro standard is determined as part of its type approval and depends on factors including the vehicle category, fuel type and applicable emissions legislation when it was approved. Euro standards may also be used by authorities to determine access to low-emission zones, but local access rules vary between countries and cities.
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What is a European emission standard?
A European emission standard, or Euro standard, classifies vehicles according to the emissions requirements they had to satisfy when approved for use in the European market.
What do Euro 4, Euro 5 and Euro 6 mean?
They are successive generations of European emission requirements. In general, a higher Euro number represents a newer and stricter emissions standard, although the exact limits differ according to vehicle and fuel type.
Which pollutants do Euro standards regulate?
Depending on the vehicle and standard, limits apply to pollutants such as nitrogen oxides, particulate matter, carbon monoxide and hydrocarbons. Newer standards also regulate additional environmental aspects.
Is the Euro standard the same as a vehicle's CO2 emissions?
No. Euro standards primarily regulate harmful air pollutants from vehicles. Carbon-dioxide emissions and fuel or energy consumption are subject to separate measurements and regulatory requirements.
How can you find a vehicle's Euro standard?
The Euro standard may appear on the vehicle registration certificate, certificate of conformity or other official vehicle documentation. Its location and format vary between countries.
Does the year of a vehicle determine its Euro standard?
The date of first registration can provide an indication, but it does not always determine the standard with certainty. The official vehicle documents or type-approval information provide the more reliable classification.
Can petrol and diesel vehicles with the same Euro number have different emission limits?
Yes. The applicable emission limits and testing requirements can differ according to the vehicle category, engine and fuel type even when vehicles belong to the same general Euro generation.
Can the Euro standard affect access to a low-emission zone?
Yes. Many low-emission zones use the vehicle's Euro standard together with factors such as fuel type and vehicle category to determine whether it may enter.
Does installing a particulate filter automatically change the Euro standard?
Not normally. The official Euro standard is linked to the vehicle's approved emissions classification. Retrofitting emission-control equipment does not necessarily result in a different official Euro classification.
What is Euro 7?
Euro 7 is the latest European emissions framework for road vehicles. It builds on earlier Euro standards and also introduces requirements covering areas such as non-exhaust particle emissions and battery durability.
