ISO 13879 pdf download.Petroleum and natural gas industries — Content and drafting of a functional specification
1 Scope
This International Standard provides guidance on the content and drafting of a functional specification. A functional specification may not be necessary if a user/purchaser wishes to obtain a known standard product, process or service manufactured/supplied to a recognized standard.
2 Normative reference
The following normative document contains provisions which, through reference in this text, constitute provisions of this International Standard. For this dated reference, subsequent amendments to, or revisions of, this publication do not apply. However, parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent edition of the normative document indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards. ISO 1 3880:— 1 ) , Petroleum and natural gas industries — Drafting and content of a technical specification .
3 Terms and definitions
For the purposes of this International Standard, the following terms and definitions apply. 3.1 functional specification document that describes the features, characteristics, process conditions, boundaries and exclusions defining the performance and use requirements of the product, process or service 3.2 technical specification document that prescribes technical requirements to be fulfilled by the product, process or service in order to comply with the functional specification NOTE A technical specification should indicate, whenever appropriate, the procedure(s) by means of which it might be determined whether the requirements given are fulfilled.
5 Framework, structure and content
5.3 General normative elements 5.3.1 Title The wording of the title should be as concise as possible and should indicate the subject matter of the functional specification, without going into unnecessary detail. The title should be composed of separate elements, each as short as possible, proceeding from the general to the particular. Not more than the following three elements should be used: a) an introductory element indicating the general field to which the functional specification belongs; b) a main element indicating the principal subject treated within that general field; c) a complementary element indicating the particular aspect of the principal subject or giving details which distinguish the document from any other functional specifications or other parts of the same functional specification. 5.3.2 Scope This element should define the subject matter of the aspect(s) covered and indicate any limits of applicability. 5.3.3 Normative references This optional element shall give a list of the normative documents to which reference is made in the standard in such a way as to make them indispensable for the application of the standard. For dated references, each shall be given with its year of publication, or in the case of enquiry or final drafts, with a dash together with a footnote “To be published” and full title. The year of publication or dash shall not be given for undated references. When an undated reference is to all parts of a standard, the publication number shall be followed by the indication “(all parts)” and the general title of the series of parts (i.e. the introductory and main elements).5.4 Functional normative elements 5.4.1 Terms and definitions This is an optional element giving definitions necessary for the understanding of certain terms used in the functional specification. The definitions should be introduced by the following wording: “For the purpose of this functional specification, the following definitions apply”. 5.4.2 Symbols and abbreviated terms This is an optional element giving a list of symbols and abbreviated terms necessary for the understanding of the functional specification. 5.4.3 Operating environment This element should provide all information known to the specifier about the environment in which the product, process or service operates.