Section 1033.740 - Credit restrictionsUse of emission credits generated under this part is restricted depending on the standards against which they were generated.
(a)Pre-2008 credits. NOX and PM credits generated before model year 2008 may be used under this part in the same manner as NOX and PM credits generated under this part.(b)General cycle restriction. Locomotives subject to both switch cycle standards and line-haul cycle standards (such as Tier 2 locomotives) may generate both switch and line-haul credits. Except as specified in paragraph (c) of this section, such credits may only be used to show compliance with standards for the same cycle for which they were generated. For example, a Tier 2 locomotive that is certified to a switch cycle NOX FEL below the applicable switch cycle standard and a line-haul cycle NOX FEL below the applicable line-haul cycle standard may generate switch cycle NOX credits for use in complying with switch cycle NOX standards and a line-haul cycle NOX credits for use in complying with line-haul cycle NOX standards.(c)Single cycle locomotives. As specified in § 1033.101 , Tier 0 switch locomotives, Tier 3 and later switch locomotives, and Tier 4 and later line-haul locomotives are not subject to both switch cycle and line-haul cycle standards.(1) When using credits generated by locomotives covered by paragraph (b) of this section for single cycle locomotives covered by this paragraph (c), you must use both switch and line-haul credits as described in this paragraph (c)(1). (i) For locomotives subject only to switch cycle standards, calculate the negative switch credits for the credit using locomotive as specified in § 1033.705 . Such locomotives also generate an equal number of negative line-haul cycle credits (in Mg).(ii) For locomotives subject only to line-haul cycle standards, calculate the negative line-haul credits for the credit using locomotive as specified in § 1033.705 . Such locomotives also generate an equal number of negative switch cycle credits (in Mg).(2) Credits generated by Tier 0, Tier 3, or Tier 4 switch locomotives may be used to show compliance with any switch cycle or line-haul cycle standards.(3) Credits generated by any line-haul locomotives may not be used by Tier 3 or later switch locomotives.(d)Tier 4 credit use. The number of Tier 4 locomotives that can be certified using credits in any year may not exceed 50 percent of the total number of Tier 4 locomotives you produce in that year for U.S. sales.(e)Other restrictions. Other sections of this part may specify additional restrictions for using emission credits under certain special provisions.73 FR 37197, June 30, 2008, as amended at 86 FR 34376, June 29, 2021