Diesel Emissions Standards Explained


Ignatius Uirab

Money Savings Advice Diesel emissions standards

In the UK and Europe, nitrogen oxide emissions in diesel must not be above 0.080g/km. Diesel emissions that are above this level can cause damage to people and the planet. Diesel emissions tests are used to check levels from cars.

Diesel cars produce emissions when their fuel is burned. Emissions are a byproduct and are created through the process of combustion. Car manufacturers must make sure that emissions are below a certain level.

Diesel emissions standards keep us all safe, making sure that there aren’t too many toxic chemicals in the air that we’re breathing. Cars must go through rigorous testing before they’re sold in the UK and Europe.

Read on to find out more about diesel emissions standards and why they exist.

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What Are Diesel Emissions?

When fuel is burned in a diesel vehicle, nitrogen oxide is produced. This is a greenhouse gas, so it can damage the ozone layer and have a negative impact on the environment around us. Nitrogen oxide doesn’t just harm the planet, but can also cause problems for people.

Nitrogen oxide diesel emissions can lead to respiratory problems. They’ve been found to be a trigger for childhood asthma and several other breathing conditions. They can also increase someone’s risk of developing other conditions like cancer. Nitrogen oxide can irritate the eyes, and when levels are too high, it has been thought to lead to cases of premature death.

What Are the UK and Europe Diesel Emissions Standards?

Around the world, different countries have different diesel emissions standards. These standards set an upper limit for the emissions produced by each vehicle. Cars can be on the road if they produce acceptable levels of diesel emissions.

In the UK and Europe, cars must produce no more than 0.080g/km of nitrogen oxide when they’re used. Diesel emissions standards are in place to protect us, and cars go through significant testing before they’re approved for sale in the UK.

In the UK there are also designated Clean Air Zones. These will come into force in Birmingham and Leeds in 2021 and will roll out in further locations after that. In order to drive in those zones, you may need to pay if your car doesn’t meet emissions standards.

You can find out more about Clean Air Zones, and whether your car will mean you need to pay, on the government’s website.

How Are Diesel Emissions Controlled?

Manufacturers control a car’s diesel emissions in a few different ways. The first way is to reduce the temperature of the combustion of diesel. An engine that burns diesel at very high temperatures naturally produces more emissions. This engine is more fuel-efficient and powerful but creates more nitrogen oxide. By burning fuel at a slightly lower temperature, diesel emissions are reduced.

Vehicle manufacturers can also use filters in their vehicles, reducing the amount of nitrogen oxide that they’ll release into the atmosphere. Filter technology can be expensive, but the best filters reduce diesel emissions by up to 90%.

Selective Catalytic Reduction (SCR) is one option for meeting the UK and European diesel emissions standards. These use a special Diesel Exhaust Fluid to convert nitrogen oxide into nitrogen, water and carbon dioxide which are safer. These are all things that we naturally find in the air.

By controlling diesel emissions, car manufacturers can make sure that we’re not at risk from toxic nitrogen oxide.

Have Diesel Emissions Standards Always Been Followed?

Diesel emissions standards haven’t always been followed, with many cars on roads around the world having produced too much nitrogen oxide. In 2014, the diesel emissions scandal became public knowledge. This was widely known as Dieselgate.

The research found that many car manufacturers had been manipulating test results.

Technology to filter diesel emissions can be expensive and hard to maintain. SCR requires regular top-ups of Diesel Exhaust Fluid, and everything is carried in onboard tanks that can weigh a car down. Other filters, too, can add to the cost of building a car that people want.

Higher combustion levels, with higher diesel emissions, make a more powerful and fuel-efficient vehicle. In short, there were many reasons for manufacturers to want to fake their way through the emissions tests.

Car Manufacturers Used Defeat Devices

Car manufacturers used defeat devices to get their cars through diesel emissions tests. These temporarily lowered the car’s emissions to below the diesel emissions standards. They usually worked by identifying when the car might be in test conditions, and using all the technology at their disposal to keep the car emissions cleaner. Once the car was outside test conditions, the filters could be used a lot less to preserve things like Diesel Exhaust Fluid.

This meant that manufacturers didn’t need to install such large onboard tanks or ask car owners to change vehicle filters outside of their usual servicing schedule. They could cut costs and make their cars a lot more appealing to drivers.

It was found that many cars produced levels of nitrogen oxide much higher than they should when they were tested in real-world driving conditions. Some produced up to 40% more diesel emissions than on paper.

After the discovery of diesel emissions test manipulation, things changed. Car manufacturers are making amends, and the diesel emissions standards tests are now much more stringent than they were. Not just taking place in test conditions, they now involve a lot of real-world driving to make sure that emissions don’t rise.

Does Your Car Meet Diesel Emissions Standards?

You might be concerned that your diesel car might not meet the current UK and European standards. If yours is an older diesel vehicle, it may have been fitted with a defeat device that would have helped it to get through the tests.

Car manufacturers recall cars with defeat devices. If yours has one, you can find out on your car manufacturer’s website. Search for ‘diesel emissions’ to see if there’s a recall, then find out if your car applies. To search for your vehicle, you’re likely to need your car’s VIN.

If your car has been recalled, it’ll need to be adjusted at an approved local workshop. Vehicle manufacturers will cover the costs of making these changes to your car, including deactivating the defeat device that falsely lowered car emissions during testing.

Can You Claim Compensation for Cars With Defeat Devices?

Many vehicle manufacturers have paid fines and penalties for cheating the tests and getting around the diesel emissions standards. You also have a right to claim compensation if you’ve been at risk as a result. You should have been told the true emissions of your diesel vehicle and may be entitled to up to 100% of your car’s original sale price.

The best way to claim compensation is to join the group action. Many other diesel car owners are doing exactly the same. Law firms are representing large numbers of compensation claimants, all wanting something back to make right what manufacturers did wrong. There’s strength in numbers, and joining group action means that you don’t need to make your own claim or fight in court individually.

To find a law firm and claim compensation, search online for ‘diesel compensation [car make]’. You’re likely to find that several different law firms are offering the chance to join the group action.

How Can Money Savings Advice Help You With Making a Compensation Claim?

Here at Money Savings Advice, we have partnered with some of the UK’s leading claims management companies. They have already helped thousands of people claim compensation, and they can do the same for you.

Choosing an independent claims management company means they won’t proceed with a claim unless they are sure it is in your best interests. They are also regulated by the FCA, which gives you an additional layer of protection.

If you would like to speak to one of these claim management companies who can help you make a compensation claim, then click on the below and answer the very simple questions.


Ignatius Uirab

Ignatius is one of our leading financial specialists. With over eight years of financial experience, he has vast experience and knowledge of the financial sector. When he is not writing about how to make your money go further, he is a true family man.

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