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22 Clauses and subclauses

22.1 Purpose or rationale

Clauses and subclauses serve as the basic components in the subdivision of the content of a document.


22.2 Title

Each clause shall have a title.


Each first level subclause (e.g. 5.1, 5.2) should preferably be given a title. Within a clause or subclause, the use of titles shall be uniform for subclauses at the same level, for example if 10.1 has a title, 10.2 shall also have a title. Figure 2 shows examples of correct and incorrect use of subclause titles.


Figure 2 - Correct and incorrect use of subclause titles



22.3 Numbering, subdivision and hanging paragraphs

22.3.1 Numbering

The clauses in each document or part shall be numbered with Arabic numerals, starting with 1 for the Scope (see Figure 3 ).


The numbering shall be continuous up to but excluding any annexes (see Clause 20).

22.3.2 Subdivision

A subclause is a numbered subdivision of a clause. A clause may be subdivided into subclauses as far as the fifth level (e.g.,

Too many levels of subdivision should be avoided, as this can make it hard for the user to understand the document.


Figure 3 provides an example of numbering of divisions and subdivisions.



Figure 3 - Example of numbering of divisions and subdivisions


A subclause shall not be created unless there is at least one further subclause at the same level. For example, text in Clause 10 shall not be designated subclause "10.1" unless there is also a subclause "10.2".

22.3.3 Hanging paragraphs

"Hanging paragraphs" shall be avoided since reference to them is ambiguous.


In the example given in Figure 4 , the hanging paragraph indicated cannot be uniquely identified as being in "Clause 5" since the paragraphs in 5.1 and 5.2 also form part of Clause 5. To avoid this problem it is necessary to identify the hanging paragraph as subclause "5.1 General" (or other suitable title) and to renumber the existing 5.1 and 5.2 accordingly (as shown), or to move the hanging paragraph elsewhere, or to delete it.


Figure 4 - Example of a hanging paragraph (left)
and one way to avoid it (right)


22.4 Referencing

Use, for example, the following forms for references to clauses and subclauses:

  • "in accordance with Clause 4";
  • "details as given in 4.1.1";
  • "the requirements given in Clause B.2";
  • "the methods described in 5.3 provide further information on...".