part_subject: "CONTROL OF EMISSIONS FROM LOCOMOTIVES"
subpart_code: "B"
subpart_subject: "Emission Standards and Related Requirements"
section_number: "1033.112"
section_subject: "Emission diagnostics for SCR systems."
cfr_reference: "40 CFR 1033.112"
title_name: "Title 40"
title_subject: "Protection of Environment"
parts_covered: "Parts 1000 to 1059"
revised_date: "Revised as of July 1, 2017"
publication_date: "As of July 1, 2017"
contains_description: "Containing a codification of documents of general applicability and future effect"
publication_info: "Published by the Office of the Federal Register National Archives and Records Administration as a Special Edition of the Federal Register"
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Engines equipped with SCR systems using separate reductant tanks must also meet the requirements of this section in addition to the requirements of § 1033.110. This section does not apply for SCR systems using the engine's fuel as the reductant.
(a)The diagnostic system must monitor reductant quality and tank levels and alert operators to the need to refill the reductant tank before it is empty, or to replace the reductant if it does not meet your concentration specifications. Unless we approve other alerts, use a malfunction-indicator light (MIL) as specified in § 1033.110 and an audible alarm. You do not need to separately monitor reductant quality if you include an exhaust NOX sensor (or other sensor) that allows you to determine inadequate reductant quality. However, tank level must be monitored in all cases.
(b)Your onboard computer must record in nonvolatile computer memory all incidents of engine operation with inadequate reductant injection or reductant quality. It must record the total amount of operation without adequate reductant. It may total the operation by hours, work, or excess NOX emissions.