When using a fusion splicer, the typical splice loss is usually between 0. 05 dB for single-mode fibre and slightly higher for multimode fibre. 1 dB is generally considered acceptable in most fibre optic networks. This guide covers the industry standards that define splice loss thresholds, how splice loss factors into the overall link budget, and how to interpret the loss numbers from the splicer and the OTDR. While intrinsic fiber losses cannot be influenced and unacceptable bending must be avoided, losses at connections during fiber optic line. This tool uses the Marcuse Gaussian Approximation to calculate losses from intrinsic mismatch and extrinsic alignment errors. Figure 1: Primary loss factors in fiber splicing: (A) Mode Field Diameter mismatch, (B) Lateral core offset, and (C) Angular misalignment.