ISO 2145

ISO 2145 is an international standard that establishes basic conventions for the numbering of divisions and subdivisions in written documents. It provides a system for hierarchical structuring of text, using Arabic numerals, to ensure clarity and ease of navigation for readers.

The standard prescribes that the first level of division within a document is indicated by the number 1. Subsequent levels of subdivision are indicated by adding further numerals, separated by periods (full stops). For example, the first subdivision of section 1 would be numbered 1.1, and a further subdivision of that would be 1.1.1. The numbers are not padded with leading zeros.

ISO 2145 aims to promote uniformity and consistency in the formatting of documents, regardless of their content or origin. This consistency helps readers to quickly understand the structure of the document and to locate the information they are seeking. It is commonly used in technical documentation, reports, and other formal writing where clear organization is essential.

The standard covers the following main aspects:

• Numbering: It specifies how sections, subsections, and further subdivisions should be numbered hierarchically.
• Hierarchy: It defines the rules for representing the hierarchical relationships between different sections.
• Consistency: It emphasizes the importance of maintaining consistency throughout the document.
• Readability: It promotes a clear and readable structure that facilitates understanding.

While widely used, ISO 2145 is not the only system for numbering document sections. Other conventions, such as using Roman numerals or letters, are also common. However, ISO 2145 is often preferred for its simplicity and clarity, particularly in technical contexts. The current version of the standard should be consulted for the most up-to-date information and application guidelines.