Answer:
The EPA regulates indoor air quality, and vehicles impact indoor air quality.
Diesel engines emit sulfur, and the EPA regulates how much sulfur should be in the air.
Explanation:
EPA is the acronym that refers to the Environmental Protection Agency, which, as the name already says, is an agency that aims to protect human health with the regulation and control of the emission, manufacture, processing, distribution and use of chemical elements that may cause environmental impacts so strong that they are capable of compromising human health. Any object, or institution, that is involved in the handling of chemicals, will be monitored by the EPA.
The transport sector is intensely regulated by the EPA, as vehicles use chemicals with high toxicity, which can be launched into the air and breathed by humans and other living beings.
