Fiber Optic Center's recommended fiber height of +/-20 nanometers enables cable assembly manufacturers to produce high-quality devices without being restricted by extremely tight tolerances that result in low yields. The Fiber Optic Association, Inc. (FOA) was founded in 1995 to help develop the workforce to build the fiber optic networks to support a rapid expansion in communications and the Internet. APPENDIX A - COVER SHEET / TOC 52. CHECK. cations, security, control and similar purposes. Although the standard covers premises installations, many of the provisions included here ar SI/ NFPA 70, the National Electrical Code (NEC). During installation, all curvatures should be smooth.