1.5. Applicability: The requirements of this specification are applicable only to components that have drawings that call out this specification. Design engineers shall use the callouts that are specified below on drawings to invoke the necessary requirements. Users of this specification shall use this section to determine which requirements of this specification are applicable.1.5.1. Cleaning Drawing Note: CLEAN PER APPLIED MATERIALS 0250-20000, APPENDIX X, CLASS Y, where X is the Appendix as defined in 1.4.1 and Y is “Class I”, “Class II”, or blank as defined in 1.4.2. “Standard” Class is the default; hence it does not need explicit designation.