10 CFR 434.99 - Explanation of numbering system for codes.
(a) For purposes of this part, a derivative of two different numbering systems will be used.
(1) For the purpose of designating a section, the system employed in the Code of Federal Regulations (CFR) will be employed. The number “434” which signifies part 434 in chapter II of Title 10, Code of Federal Regulations, is used as a prefix for all section headings. The suffix is a two or three digit section number. For example the lighting section of the standards is designated § 434.401.
(2) Within each section, a numbering system common to many national voluntary consensus standards is used. A decimal system is used to denote paragraphs and subparagraphs within a section. For example, in § 434.401, “401.2.1” refers to subsection 401, paragraph 2, subparagraph 1.
(b) The hybrid numbering system is used for two purposes:
(1) The use of the Code of Federal Regulations' numbering system allows the researcher using the CFR easy access to the standards.
(2) The use of the second system allows the builder, designer, architect or engineer easy access because they are familiar to this system numbering. This system was chosen because of its commonality among the building industry.