(a) For the purpose of determining the applicability of section 216(10) of the Act, any marine SI engine as that term is defined in subpart A of this part, is deemed a nonroad engine.

(b) EPA will maintain a list of models of marine SI engines, and the marine vessels which use such engines, that have been determined to be excluded because they are used solely for competition. This list will be available to the public and may be obtained by writing to the following address: Group Manager, Engine Compliance Programs Group, Engine Programs and Compliance Division (6403J), Environmental Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460.

(c) Upon written request with supporting documentation, EPA will make written determinations as to whether certain engines are or are not marine SI engines. Engines that are determined not to be marine SI engines are excluded from regulations under this part but may be subject to regulations under another part.