What agency is responsible for ensuring that freight trucks adhere to emission standards?

The Environmental Protection Agency (EPA) is responsible for ensuring that freight trucks adhere to emission standards. This agency is tasked with protecting human health and the environment by regulating emissions from various sources, including vehicles. The EPA sets and enforces standards that govern the air pollution caused by trucks and other types of industrial emissions.

By establishing these emission standards, the EPA plays a crucial role in improving air quality and reducing harmful pollutants released into the atmosphere. This regulatory responsibility includes monitoring compliance and implementing programs aimed at reducing emissions from freight trucks, thus contributing to environmental sustainability and public health.

While other agencies like the Department of Transportation and the Federal Motor Carrier Safety Administration oversee various aspects of transportation safety, their primary focus does not revolve around environmental regulations or emissions control. The National Highway Traffic Safety Administration concentrates more on vehicle safety standards rather than specifically dealing with emissions. Hence, the definitive responsibility for emission standards falls under the jurisdiction of the EPA.