---identifier: "/us/cfr/t40/s405.81"source: "ecfr"legal_status: "authoritative_unofficial"title: "40 CFR § 405.81 - Specialized definitions."title_number: 40title_name: "Protection of Environment"section_number: "405.81"section_name: "Specialized definitions."chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"subchapter_number: "N"subchapter_name: "EFFLUENT GUIDELINES AND STANDARDS"part_number: "405"part_name: "DAIRY PRODUCTS PROCESSING POINT SOURCE CATEGORY"positive_law: falsecurrency: "2026-03-24"last_updated: "2026-03-24"format_version: "1.1.0"generator: "[email protected]"authority: "Secs. 301, 304 (b) and (c), 306 (b) and (c) and 307(c) of the Federal Water Pollution Control Act, as amended (the Act); 33 U.S.C. 1251, 1311, 1314 (b) and (c), 1316 (b) and (c), and 1317(c); 86 Stat. 816, Pub. L. 92-500; 91 Stat. 1567, Pub. L. 95-217."regulatory_source: "39 FR 18597, May 28, 1974, unless otherwise noted."cfr_part: "405"---
Identifier
/us/cfr/t40/s405.81
Currency
2026-03-24
Positive Law
No
Updated
2026-03-24
Chapter
Environmental Protection Agency
Authority
Secs. 301, 304 (b) and (c), 306 (b) and (c) and 307(c) of the Federal Water Pollution Control Act, as amended (the Act); 33 U.S.C. 1251, 1311, 1314 (b) and (c), 1316 (b) and (c), and 1317(c); 86 Stat.... Secs. 301, 304 (b) and (c), 306 (b) and (c) and 307(c) of the Federal Water Pollution Control Act, as amended (the Act); 33 U.S.C. 1251, 1311, 1314 (b) and (c), 1316 (b) and (c), and 1317(c); 86 Stat. 816, Pub. L. 92-500; 91 Stat. 1567, Pub. L. 95-217.
# 405.81 Specialized definitions.For the purpose of this subpart:(a) Except as provided below, the general definitions, abbreviations and methods of analysis set forth in part 401 of this chapter, shall apply to this subpart.(b) The term “BOD*5* input” shall mean the biochemical oxygen demand of the materials entered into process. It can be calculated by multiplying the fats, proteins and carbohydrates by factors of 0.890, 1.031 and 0.691 respectively. Organic acids (e.g., lactic acids) should be included as carbohydrates. Composition of input materials may be based on either direct analyses or generally accepted published values.