part_subject: "CONTROL OF EMISSIONS FROM NEW AND IN-USE HEAVY-DUTY HIGHWAY ENGINES"
subpart_code: "I"
subpart_subject: "Definitions and Other Reference Information"
section_number: "1036.805"
section_subject: "Symbols, abbreviations, and acronyms."
cfr_reference: "40 CFR 1036.805"
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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The procedures in this part generally follow either the International System of Units (SI) or the United States customary units, as detailed in NIST Special Publication 811 (incorporated by reference in § 1036.810). See 40 CFR 1065.20 for specific provisions related to these conventions. This section summarizes the way we use symbols, units of measure, and other abbreviations.
(a)Symbols for chemical species. This part uses the following symbols for chemical species and exhaust constituents:
(b)Symbols for quantities. This part uses the following symbols and units of measure for various quantities:
(c)Superscripts. This part uses the following superscripts to define a quantity:
(d)Subscripts. This part uses the following subscripts to define a quantity:
(e)Other acronyms and abbreviations. This part uses the following additional abbreviations and acronyms:
(f)Prefixes. This part uses the following prefixes to define a quantity: