The definitions in subpart A of this part apply to this subpart. The following definitions shall also apply to this subpart:

Averaging means the exchange of marine engine in-use emission credits among engine families within a given manufacturer's product line.

Banking means the retention of marine engine in-use emission credits by the manufacturer generating the emission credits for use in future model year averaging or trading as permitted by these regulations.

Carry-over engine family means an engine family which undergoes certification using carryover test data from previous model years. See §91.118(c).

Emission credits or in-use credits represent the amount of emission reduction or exceedance, for each regulated pollutant, by a marine engine family below or above, respectively, the applicable certification family emission limit (FEL) to which the engine family is certified. Emission reductions below the FEL are considered “positive credits,” while emission exceedances above the FEL are considered “negative or required credits.”

Banked credits refer to positive emission credits based on actual applicable production/sales volume as contained in the end of model year in-use testing reports submitted to EPA. Some or all of these banked credits may be revoked if EPA review of the end of model year in-use testing reports or any subsequent audit action(s) uncovers problems or errors.

Trading means the exchange of marine SI engine in-use emission credits between manufacturers and/or brokers.

Compliance level for an engine family is determined by averaging the in-use test results from each engine.