This Part of this European Standard is applicable to CO 2 -laser beam machines for welding and cutting in two operating directions (2D). The main purpose of this standard is to provide requirements for acceptance testing of CO 2 -laser beam machines prior to or during installation at the user’s premises . The acceptance tests are used to document the ability of CO 2 -laser beam machines to produce welded joints and cuts of consistent quality. This standard is intended to be used for preparation of the technical specification for CO 2 -laser beam ma-chines for high quality welding and cutting in two operating directions (2D). This standard specifies basic requirements. Additional tests and requirements may be specified in the technical specification for the CO 2 -laser beam machine. NOTE 1 The technical specification for the CO 2 -laser beam machine usually forms a part of the contract and it is agreed by the parties concerned (the manufacturer of the CO 2 -laser beam machine and the customer/user). NOTE 2 The requirements may be too stringent for non-high quality cutting. However, the standard may also be used for testing as part of maintenance, as appropriate. If modifications are made to a CO 2 -laser beam machine (rebuilding, repairs, modifications to the oper-ating conditions etc.) that may have an effect on the acceptance testing, repeat test may be neces-sary covering the machine parameters affected by such modifications. If a CO 2 -laser beam machine that has already been accepted is dismantled (e.g. in order to change its location) such tests may involve verification according to the requirements in 6.4 as a minimum.