California Air Resources Board

The In-Use Locomotive Regulation (Regulation) will achieve emission reductions from diesel-powered locomotives. The Regulation will help meet California’s public health, air quality and climate goals by reducing criteria pollutants, toxic air contaminants, and greenhouse gas emissions for locomotives in-use.  

• Historic locomotives are kept in their original configuration to help interpret historical experiences and serve educational purposes transporting passengers.
• There are currently 23 operational diesel‑powered historic locomotives in California.
• Historic locomotive operators have worked with CARB staff to identify a compliance path that limits emissions, and retains reporting requirements, but allows historic locomotives to continue in their educational and interpretive roles.
• Emissions from historic locomotives are not fully documented; due to this insufficient information, emissions from historic locomotives are not included in the emissions inventory for the Regulation.

Compliance with the Regulation

• The Regulation provides exemptions for historic locomotive operators that qualify.
• Exemptions could apply for demonstration museums, education, tourist railways and historic preservation purposes or any special one-time movements not used to haul freight for hire.
• Some provisions in the Regulation apply to all operators, regardless of approved exemption; those provisions are:

 Idling Limit

• Locomotives with automatic shutoff: locomotive will be required to shut off no more than 30 minutes after the locomotive becomes stationary. A locomotive will be permitted to exceed 30 minutes of idling for only for an exempt reason, the Regulation lists reasons for exemption.

Registration and Reporting

• Locomotives operating in the California will be required to register with CARB.
• Locomotive activity, emission levels, and idling data must be reported annually.