In Utah, Salt Lake County Mayor Jenny Wilson announced Oct. 13 that the county has committed to only purchasing Tier 3 gas for its fleet of 750 vehicles.

Tier 3 gas stems from an Environmental Protection Agency (EPA) standard regulating fuel efficiency in cars and the sulfur content of gasoline. In vehicles made after 2017, Tier 3 gas can reduce harmful emissions by as much as 80%. In older vehicles, that figure stands at 13%.

“Air quality is a top priority in my administration, and we’re putting action behind that,” Wilson said. “We challenge all other entities, businesses, and residents to make this same commitment to only purchase Tier 3 gas moving forward.”

In 2017, the Utah Legislature passed a bill that granted refineries a significant tax credit to make Tier 3 gas. While several gas station retailers across Utah purchase from refineries that have made the switch to producing Tier 3 gas, not all refineries have embraced this EPA standard. Shell, Speedway, Sinclair, Exxon, Chevron, and Texaco are all providers of Tier 3 gas.

To help residents and others identify where to find Tier 3 gas, the state launched a website and a map in 2020.