ISO 3834-1 gives the criteria for the selection of the appropriate level of the quality requirements. Section 5 states: The selection of the appropriate part of ISO 3834, specifying the required level of quality requirements, should be in accordance with the product standard, specification, regulation or contract. Because ISO 3834 may be used in a variety of situations and for different applications, definite rules on the level of quality requirements to be adopted in individual circumstances

ISO 3834 may be applied to a variety of situations.

The manufacturer should select one of the three parts specifying different levels of quality requirements, based on the following criteria related to products:

• the extent and significance of safety-critical products
• the complexity of manufacturer
• the range of products manufactured
• the range of different materials used
• the extent to which metallurgical problems occur
• the extent to which manufacturing imperfections, e.g. misalignment, distortion or weld imperfections, affect product performance.