The IPC-D-640A standard provides design and critical process requirements and technical insight for cable and wire harness assemblies incorporating optical fiber, optical cable and hybrid wiring technology. The IPC-D-640A standard is intended to provide information on the general design requirements for optical fiber, optical cable, hybrid wiring harness assemblies, and Fiber Optic Communications Systems (FOCS) to the extent that they can be applied to the broad spectrum of optical cable and wiring harness design. The IPC-D-640A is intended for use by the design engineer, manufacturing engineer, quality engineer, or other individual, responsible for the tailoring of specific requirements of this document to the applicable performance classes