Used in conjunction with IPC-2221, IPC-2222 establishes the specific requirements for the design of rigid organic printed boards and other forms of component mounting and interconnecting structures. This standard applies to single-sided, double-sided or multi-layered boards. Key concepts in this document are: rigid laminate properties, design requirements for printed board assembly and design requirements for holes/interconnections. Revision A provides new design guidance and requirements for dielectric spacing, lead-free laminate materials, scoring and routing parameters, printed board thickness tolerance, nonfunctional lands, hole aspect ratios and clearance areas in planes.33 pages. Released December 2010.