The U.S. Environmental Protection Agency is eyeing promulgating stricter regulations for locomotive regulations.
The agency has formed a study group to examine options and recommendations for possible new regulations that would seek to cut emissions from locomotives.
Higher standards are being sought from the EPA by the California Air Resource Board, which has cited complaints from workers and those who live near railroad yards and ports of respiratory illness and premature death caused by locomotive emissions.
The existing EPA locomotive emission standards, known as Tier 4 regulations, were created in 2008.
Although Class 1 railroad motive fleets include Tier 4 compliant locomotives, many carriers continue to rely on older locomotives, although some older units have been rebuilt to reduce emissions.
However, these rebuilt locomotives do not need to meet Tier 4 standards.
Class 1 railroads have pruned the size of their motive power fleets in response to the adoption of the precision scheduled railroading operating model, which relies on fewer and longer trains.
In 2021 U.S. Class 1 railroads ordered no new locomotives and in 2020 they ordered just 94 units.
A report posted on the website of Trains magazine observed that locomotive builders believe the future of railroad motive power lies more with such technology as batteries, battery-diesel hybrids, and hydrogen fuel cells than it does with diesel power alone.