Exhaust fumes can be harmful to health and the environment, and with rising awareness of the impact of exhaust fumes on public health, vehicle owners are being more cautious about the cars that they choose to drive.
In this series, we will cover everything you need to know about vehicle exhaust emissions, starting with what emissions are, and what gases they tend to contain.
What are exhaust emissions?
Your exhaust pipe’s job is to safely dispose of the byproducts made by your engine when it propels your car. Exhaust fumes contain a combination of particles and gases that are released by your engine when it is running. In areas of heavy congestion, a build up of these emissions can have a serious impact on air quality.
As well as the impact in physical health and local air quality, exhaust fumes are a major contributor to global warming. In the UK, exhaust fumes constitute nearly a quarter of all greenhouse gas emissions, as well as containing other dangerous pollutants.
What gases do exhaust fumes contain?
We have all heard of carbon footprint and CO2, but there are many other dangerous gases released by a combustion engine:
Carbon Monoxide (CO) - An invisible gas produced during incomplete fuel combustion, carbon monoxide is highly toxic to humans. Modern engines generate minimal amounts of CO due to efficient combustion processes.
Nitrogen Oxides (NOx) - NOx is a byproduct of combustion in any engine. These reactive compounds can exacerbate smog when they react with other airborne chemicals.
Sulphur Dioxide (SO2) - This colourless gas, with a burnt matches odour, occurs naturally in crude oil used in refining petrol and diesel. When burned, it forms acids that lead to engine corrosion and smog.
Hydrocarbons (HC) - HC escapes from exhaust systems as unburned fuel due to incomplete combustion and evaporates from fuel tanks and nozzles during refuelling.
Benzene (C6H6) - Present in petrol and diesel in trace amounts, this carcinogenic substance is emitted from the vehicle exhaust as unburned fuel.
Particulates - Diesel engines release airborne particles like black soot and metal, collectively known as particulate matter. Modern vehicles are equipped with diesel particulate filters (DPFs) to reduce the release of harmful particles into the atmosphere.
By keeping your vehicle in good condition, you can help to reduce your fuel consumption and prevent production of excess emissions; make sure that your vehicle is serviced regularly and consult your local mechanic if you notice more fumes than normal. For more information on emissions, follow Trust A Garage on Facebook or X; next week we will be discussing the impact of emissions, and how you can reduce them.