The Clean Truck Check program, also known as the HD/IM program, is a program that was implemented in 2023 to start to address the emissions that are emitted by diesel powered vehicles. Currently in California there is a smog program that targets the emissions for a gas powered vehicles and some diesel vehicles. However, the HDIM program, which was passed by Senate Bill 210, largely targets larger vehicles that were previously exempt from any emissions standards, this even includes diesel powered motorhomes.
This program is very extensive and is a clear indication that California takes emissions very seriously.
These are some quick stats for the HDIM program on :