(a) OSVs of less than 6,000 GT ITC (500 GRT if GT ITC is not assigned). (1) Except as provided in paragraph (a)(2) of this section, each internal-combustion engine installed on an OSV of less than 6,000 GT ITC (500 GRT if GT ITC is not assigned), whether for main propulsion or for auxiliaries, must be driven by a fuel having a flashpoint of not lower than 43 °C (110 °F) as determined by ASTM D 93 (incorporated by reference, see § 125.180).

(2) The use of a fuel with a flashpoint of lower than 43 °C (110 °F) must be specifically approved by the Commandant (CG-ENG), except in an engine for a gasoline-powered rescue boat.

(b) OSVs of at least 6,000 GT ITC (500 GRT if GT ITC is not assigned). (1) Except as provided by paragraph (b)(2) of this section, each internal-combustion engine installed on an OSV of at least 6,000 GT ITC (500 GRT if GT ITC is not assigned), whether for main propulsion or for auxiliaries, must be driven by a fuel having a flashpoint not lower than 60 °C (140 °F) as determined by ASTM D 93 (incorporated by reference, see § 125.180).

(2) The use of a fuel with a flashpoint lower than 60 °C (140 °F) must be specifically approved by the Commandant (CG-ENG), except in an engine for a gasoline-powered rescue boat or emergency generator, or as provided in paragraph (b)(2) of this section.

No diesel-engine exhaust system need meet the material requirements in § 58.10-5(d)(1)(i) of this chapter if the installation is certified as required by § 128.220(c) of this part.