1.1 This part of ISO 9327 covers the technical delivery conditions for forgings (see note 1) and for rolled or forged bars for pressure purposes manufactured from the following internationally used steels (see note 2): a) non-alloy and alloy ferritic or martensitic steels with specified room temperature properties and supplementary requirements for elevated temperature properties covered in ISO 9327-2; b) nickel steels with specified low temperature properties covered in ISO 9327-3; c) weldable fine grain steels with high proof strength (room temperature, elevated temperature and low temperature grades) covered in ISO 9327-4; d) austenitic and austenitic-ferritic steels (room temperature and elevated temperature grades) covered in ISO 9327-5. NOTE 1 In accordance with ISO 6929 the term forgings covers here open die forgings including ring rolled products as well as closed die forgings. NOTE 2 Additional to the internationally used steels for pressure purposes covered in parts 2 to 5 of ISO 9327, there are other steels used regionally or nationally for the same application. These other steels shall not be precluded by this International Standard provided that they comply with the relevant International or National Standards for vessel constructions. NOTE 3 The following International Standards also apply for steel products for pressure purposes: ISO 9328 parts 1 to 5, ISO 9329 parts 1 to 4, ISO 9330 parts 1 to 6, ISO 4978. 1.2 In special cases variations of the requirements of this International Standard or additions to them may form the subject of an agreement at the time of enquiry and order (see annex C). 1.3 In addition to the requirements of this International Standard the general technical delivery requirements in ISO 404 apply, unless otherwise indicated in the following.