The environmental class of a car is a category that reflects the level of environmental pollution created by a vehicle during operation. It is determined based on the amount and composition of harmful substances emitted into the atmosphere with exhaust gases.

ZEV / Zero Emission Vehicle / zero emission vehicle, assigned to electric vehicles

EURO STANDARDS:
Euro 1 / 1992 / Catalytic converter required; switch to unleaded petrol
Euro 2 / 1996 / Stricter CO and HC+NOx limits; fuel-type differentiation
Euro 3 / 2000 / Separate HC and NOx limits; no warm-up phase in test cycle
Euro 4 / 2005 / Major emission reduction; prep for particulate filters
Euro 5 / 2009 / PM limits; mandatory filters for diesel and direct injection
Euro 6 / 2014 / Strictest NOx limits; real-world testing introduced
Euro 6d /2020 / RDE tests introduced; real-world emissions compliance
Euro 7 / 2025 / Includes non-exhaust emissions (brakes, tyres); lifetime compliance

USA STANDARDS:
Tier 1 (USA) / 1994 / Initial federal limits; CO and NOx reduction
Tier 2 (USA) / 2004 / Vehicle class-based limits; evaporative emissions control
Tier 3 (USA) / NOx and PM reduction; fuel standard alignment

CHINA STANDARDS:
China I / 2000 / First national standard; similar to Euro 1
China II / 2004 / Stricter CO and NOx limits; start of evaporative emissions control
China III / 2007 / OBD requirements introduced; vehicle mass-based classification
China IV / 2010 / Lower NOx and PM limits; mandatory diesel particulate filters
China V / 2016 / Similar to Euro 5; standards for gasoline and diesel vehicles
China VI-a / 2020 / Real Driving Emissions (RDE); fuel-neutral standards
China VI-b / 2023 / Tighter NOx and PM limits; durability control; telematics monitoring
China VII / 2025 / Includes non-exhaust emissions; brake dust control; lifetime compliance

The Chinese standards are based on Euro, but since version 6 they have started to include their own elements: telemetry, advanced climate conditions, evaporative emission control and durability. China VII will be one of the most stringent standards in the world.

The environmental class is a standard indicator introduced to:
– assess the toxicity of vehicle emissions;
– regulate the admission of vehicles to operation;
– encourage manufacturers to implement environmentally friendly technologies.
It affects:
– the possibility of importing and registering a vehicle in the country;
– tax rates and fees;
– access to environmental zones (for example, in cities with emission restrictions);
– the price and liquidity of the vehicle on the secondary market.

When certifying a vehicle, the following are analyzed:
– carbon monoxide emissions (CO);
– hydrocarbons (HC);
– nitrogen oxides (NOx);
– particulate matter (PM);
– fuel evaporation;
– sometimes — non-exhaust emissions (brake dust, tire wear).

The first international standard was Euro 1 in 1992. Since then, environmental classes have developed in increasing severity:
– Euro 1–6/6d/7 — Europe;
– Tier 1–3 — USA (EPA);
– China I–VI — China;
– Bharat Stage I–VI — India;
– JP 2000–Post New Long-Term — Japan.
Each class sets the maximum permissible emission levels that a car must not exceed.

Why is this important:
– Some countries prohibit the import of cars below a certain level; for example, in Russia, since 2016, the import of cars of a class below Euro 5 has been prohibited;
– In cities in Europe and the USA, there are zones with limited access for cars with a low environmental class.
– In the future, the environmental class may affect insurance, parking, and even the price of fuel.