Since coming into force in 1992, the Euro emissions standards have undeniably improved air quality and public health. But what are the Euro emission standards and what should you look out for when buying a used car?

In this article, we’ll explore the Euro emissions standards and explain why they’re an important element to consider.

What are the Euro emission standards?

The Euro emissions standards are a set of regulations introduced to cut down the pollutants released by vehicles, helping to reduce the carbon footprint vehicles of UK and Europe.

After its introduction in 1992, the first Euro standard (Euro 1) saw changes to production standards before vehicles were approved for the road. This included the requirement for a catalytic converter on all cars produced after the standards began. Since then, the Euro emissions standards have gone through numerous updates to progressively restrict the release of harmful chemicals into the environment.

Why were the Euro emission standards introduced?

The Euro emission standards were introduced to reduce harmful toxins found in exhaust fumes from combustion-powered cars, trucks, and motorbikes. These vehicles emit harmful toxins such as nitrogen oxide (NOx), carbon monoxide (CO), hydrocarbons (HC) and particulate matter (PM) all of which are dangerous to the environment and population.

Figures from the Society of Motor Manufacturers and Traders (SMMT) have shown that since 1993, carbon monoxide levels are down more than 62% on petrol-powered vehicles and 82% on diesel vehicles. Nitrogen oxide has also been reduced significantly, with figures improving by 84% since 2001, whilst particulate matter has been reduced by 93% in 24 years.

Also, diesel cars, which produce a black soot-like substance that blasts out the exhaust, are now fitted (by law) with diesel particulate filters. In effect since 2006, these particulate filters collect 99% of particulate materials. It’s an important point, as the contents of such emissions could cause respiratory issues. Again, this is the result of the Euro emission standards.

What Euro standard is my car?

Which Euro standard your vehicle complies with depends on its date of registration. If your car is registered prior to the Emissions standard being introduced, there is no requirement for your vehicle to comply with the new set of regulations.

Emissions standard Car registered from
Euro 1 31st December 1992
Euro 2 1st January 1997
Euro 3 1st January 2001
Euro 4 1st January 2006
Euro 5 1st January 2011
Euro 6 1st January 2015*

*some cars sold before 1st September 2016 may still have a Euro 5 engine. Be sure to check with the manufacturer/seller in advance.

Why do I need to know my car’s Euro emission standard?

Knowing the Euro emissions standards group for any vehicles you’re considering is beneficial for a variety of reasons. Firstly, it can help you understand what parts the vehicle has, allowing you to conduct proper checks before committing to a purchase. For example, all Euro 5 and 6 diesel vehicles must have a diesel particulate filter (DPF) fitted, which is a common failure point on MOTs.

Large cities such as London, Birmingham and Bristol have also begun to introduce Ultra-Low Emission Zones (ULEZ). These zones are intended to reduce pollution and whether you need to pay a charge is dependent on the Euro emission standard of your vehicle.

Vehicles produced in line with Euro 4 for petrol and Euro 6 standards for diesel are exempt as well as fully electric vehicles. However, if your vehicle is below this, you will need to pay a daily charge.

How to get proof of your vehicle’s Euro emission standards

Aside from using the date that your car was registered, there are a number of ways you can confirm the Euro emission standard of your vehicle. For newer vehicles in the UK, this information should be listed in section D of the vehicle’s log book (V5C), also known as the vehicle registration certificate. On some vehicles, the Euro emissions standard can be found inside the passenger or driver’s door frame, too.

Alternatively, if you are in the process of purchasing a vehicle, the dealer will be able to provide you with this information.

Whilst the table we have provided above indicates what emission standard your vehicle is, it’s always worth checking the official documentation of your vehicle.

What are the Euro 1 emission standards?

Euro 1 was the first Europe-wide emissions standard introduced in July 1992. It required all new petrol cars to switch to unleaded fuel and have catalytic converters fitted to reduce carbon monoxide. Only hydrocarbons and nitrogen oxide were tested, along with particulate matter for diesel engines.

Euro 1 emission limits

Emission Limit
CO 2.72 g/km (petrol and diesel)
HC and NOx 0.97 g/km (petrol and diesel)
PM 0.14 g/km (diesel only)

What are the Euro 2 emission standards?

In January 1996, Euro 2 emission standards introduced different emission limits for petrol and diesel cars. It reduced the limit for carbon monoxide and further reduced the combined emission limit for unburned hydrocarbons and nitrogen oxides for both types of vehicle.

Euro 2 emission limits – Petrol

Emission Limit
CO 2.2 g/km
HC and NOx 0.5 g/km
PM No limit

Euro 2 emission limits – Diesel

Emission Limit
CO 1.0 g/km
HC+ NOx 0.7 g/km
PM 0.08 g/km

What are the Euro 3 emission standards?

With the incoming of Euro 3 in January 2000, the test procedure for emissions was changed in order to stop manufacturers from using an engine-warm up period. A limit on the number of nitrogen oxides (NOx) emitted from diesels was also implemented, along with separate hydrocarbon and NOx limits for petrol engines. Permitted carbon monoxide and diesel particulate limits were also further reduced.

Euro 3 emission limits – Petrol

Emission Limit
CO 2.3 g/km
HC 0.20 g/km
NOx 0.15 g/km
PM No limit

 

Euro 3 emission limits – Diesel

Emission Limit
CO 0.64 g/km
HC+ NOx 0.56 g/km
NOx 0.50 g/km
PM 0.05 g/km

What are the Euro 4 emission standards?

In January 2005, the Euro 4 emission standards brought tougher sanctions to tackle the emissions from diesel engines, which were fast becoming popular because of their excellent fuel economy. This was also the first time many cars were being fitted with diesel particulate filters to reduce particulate matter (PM).

Euro 4 emission limits – Petrol

Emission Limit
CO 1.0 g/km
HC 0.10 g/km
NOx 0.08 g/km
PM No limit

Euro 4 emission limits – Diesel

Emission Limit
CO 0.50 g/km
HC+ NOx 0.30 g/km
NOx 0.25 g/km
PM 0.025 g/km

What are the Euro 5 emission standards?

The focus is on diesel cars and their emissions with the introduction of Euro 5 in September 2009. Euro 5 emissions reduced the limit on nitrogen oxides from diesel-powered cars by 28%, and diesel particulate filters (DPFs) were needed by all diesel-powered vehicles to meet the new requirements, capturing 99% of particulate matter. A particulate limit was also introduced to petrol cars with direct injection engines. Limits were also reduced across the board.

Euro 5 emission limits – Petrol

Emission Limit
CO 1.0 g/km
HC 0.10 g/km
NOx 0.06 g/km
PM 0.005 g/km (direct injection only)

Euro 5 emission limits – Diesel

Emission Limit
CO 0.50 g/km
HC+ NOx 0.23 g/km
NOx 0.18 g/km
PM 0.005 g/km
PM 6.0×10 ^11/km

What are the Euro 6 emission standards?

The Euro 6 emission standards, introduced in September 2014, is the sixth and current standard for all new cars. The Euro 6 has seen a greater reduction in nitrogen oxides (NOx), which are reduced a further 67% from the previous Euro emission standards check, going from 0.18g/km in Euro 5, to just 0.08g/km. Many cars now use additives, via Selective Catalytic Reduction (SCR), to convert harmful gasses emitted from diesel into nitrogen and water.

Euro 6 emission limits – Petrol

Emission Limit
CO 1.0 g/km
HC 0.10 g/km
NOx 0.06 g/km
PM 0.005 g/km (direct injection only)
PM 6.0×10 ^11/km (direct injection only)

Euro 6 emission limits – Diesel

Emission Limit
CO 0.50 g/km
HC+ NOx 0.17 g/km
NOx 0.08 g/km
PM 0.005 g/km
PM 6.0×10 ^11/km

When will Euro 7 emission standards be introduced and what will change?

Euro 7 emission standards will be implemented on 1 July 2025 which will introduce the lowest limits across all new petrol and diesel cars.

Once introduced, all new cars must not emit more than 60 milligrams of NOx, while a wider range of conditions, including limits on the amount of particle matter produced by brakes and tyres and an assessment of the performance and longevity of batteries in electric and hybrid vehicles, will also be brought in.

Technology is improving in line with these standards too, so there’s nothing to worry about. For example, new vehicles will be fitted with sensors aimed at detecting any engine faults that could cause emissions to rise above the limits, allowing you to resolve these problems in good time.

Much like the other standards, existing vehicles will not be required to comply with the Euro 7 standards once introduced.

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