What defines a partial zero emissions vehicle (PZEV)?

A partial zero emissions vehicle (PZEV) is defined as a gasoline-powered vehicle that has been designed to achieve near-zero emissions of harmful pollutants. This includes ensuring that the vehicle has zero evaporative emissions from its fuel system, meaning that no harmful vapors escape into the atmosphere during operation or when parked. This feature significantly minimizes the vehicle's impact on air quality, contributing to the overall reduction of pollution.

The designation of PZEV typically applies to vehicles that meet stringent emissions standards set by regulatory agencies. This is crucial for improving air quality and reducing the environmental impact of transportation. While some other vehicle types, such as plug-in electric vehicles or those with hybrid drivetrains, have low emissions, they do not necessarily qualify as PZEVs as they may still emit some pollutants or have other factors that prevent them from being considered partial zero emissions.

Thus, the focus on zero evaporative emissions in gas-engine vehicles is what distinctly characterizes a PZEV.