Code of Federal Regulations > Title 40 > Chapter I > Part 1045 > Subpart I > Appendix Appendix II - Appendix II to Part 1045—Duty Cycles for Propulsion Marine Engines

Regulations last checked for updates: Nov 01, 2025

Title 40 - Protection of Environment last revised: Sep 01, 2029

Appendix Appendix II - Appendix II to Part 1045—Duty Cycles for Propulsion Marine Engines

(a) The following duty cycle applies for discrete-mode testing:

E4 Mode No.	Engine speed ¹	Torque (percent) ²	Weighting factors
1	Maximum test speed	100	0.06
2	80%	71.6	0.14
3	60%	46.5	0.15
4	40%	25.3	0.25
5	Warm idle	0	0.40

¹ Speed terms are defined in 40 CFR part 1065. Percent speed values are relative to maximum test speed.

² Except as noted in § 1045.505, the percent torque is relative to maximum torque at maximum test speed.

(b) The following duty cycle applies for ramped-modal testing:

RMC Mode	Time in mode (seconds)	Engine speed ^{1 2}	Torque (percent) ^{2 3}
1a Steady-state	225	Idle	0
1b Transition	20	Linear transition	Linear transition
2a Steady-state	63	Maximum test speed	100
2b Transition	20	Linear transition	Linear transition
*3a Steady-state	271	40%	25.3%
3b Transition	20	Linear transition	Linear transition
4a Steady-state	151	80%	71.6%
4b Transition	20	Linear transition	Linear transition
5a Steady-state	161	60%	46.5%
5b Transition	20	Linear transition	Linear transition
6 Steady-state	229	Warm idle	0

¹ Speed terms are defined in 40 CFR part 1065. Percent speed values are relative to maximum test speed.

² Advance from one mode to the next within a 20-second transition phase. During the transition phase, command linear progressions of speed and torque from the speed setting and torque setting of the current mode to the speed setting and torque setting of the next mode.

³ Except as noted in § 1045.505, the percent torque is relative to maximum torque at maximum test speed.

authority: 42 U.S.C. 7401-7671q.

source: 73 FR 59194, Oct. 8, 2008, unless otherwise noted.