Existing law generally regulates the operation of vessels and associated equipment used, to be used, or carried in vessels used on waters subject to the jurisdiction of the state. Existing regulations require the installation of a new engine or the retrofit of an existing engine in certain harbor craft to reduce emissions of air pollutants, as specified. This bill would require a diesel particulate filter that is retrofitted onto the engine of certain commercial harbor craft to include an override or bypass safety system that ensures that the commercial harbor craft can maintain a safe level of propulsion in the event of an emergency situation, as specified. The bill would require the manufacturer of an override or bypass safety system to design, install, and provide certain documentation regarding the override or bypass safety system, as specified. The bill would require the owner or operator of a commercial harbor craft that uses an override or bypass safety system to report the use and retain records regarding the use, as specified. This bill would delay the regulatory requirement to install a new engine or retrofit an existing engine in certain harbor craft, as specified.