The California Air Resources Board (CARB) continues to get push back on a commercial harbor craft (CHC) regulation slammed as “unworkable” and “deeply flawed” by the American Waterways Operators (AWO), even before they went into force. AWO noted that, among other things, the CARB CHCn regulation mandates engine technology that is not available and is not certified as safe by the U.S. Coast Guard.
One of those technologies is the diesel particulate filters (DPFs) called for by the CARB...
https://www.marinelog.com/inland-coastal/uscg-wont-enforce-controversial-carb-chc-regulation/