EURO 4 refers to the fourth iteration of emission standards set by the European Union (EU) for cars. These standards are designed to regulate and limit the levels of harmful pollutants emitted by cars with internal combustion engines. EURO 4 standards apply to both petrol (gasoline) and diesel-powered cars.
The EURO 4 standards were implemented in two phases:
EURO 4a: This phase was implemented from January 2005 and focused on regulating emissions from diesel cars. It set limits for various pollutants, including nitrogen oxides (NOx), particulate matter (PM), carbon monoxide (CO), and hydrocarbons (HC). The emission limits for petrol cars remained largely similar to the previous EURO 3 standards.
EURO 4b: This phase was implemented from January 2006 and expanded the emission standards to include petrol cars as well. It tightened the limits for both diesel and petrol cars, particularly focusing on reducing NOx and other pollutant emissions.
The EURO 4 standards introduced more stringent requirements for car manufacturers, leading to the development and implementation of advanced emission control technologies. These technologies included the use of catalytic converters, improved engine management systems, and more efficient exhaust gas recirculation (EGR) systems.
Compared to earlier EURO standards, EURO 4 reduced the allowed levels of harmful emissions, contributing to improved air quality and reduced environmental impact. These standards played a significant role in the adoption of cleaner and more fuel-efficient cars in the European market.
It’s important to note that EURO 4 standards are specific to the European Union and apply to new cars sold within the EU member states. Other regions and countries may have their own emission standards, such as the EPA standards in the United States or China 4 standards in China, which have similar goals of reducing car emissions and improving air quality.