Applies to optical fibre amplifiers (OFAs) using active fibres, containing rare-earth dopants, presently commercially available. Provides the general background for OFA noise figure parameters measurements and indicates those IEC standard test methods for accurate and reliable measurements of the following OFA parameters: noise figure, noise factor, multiple path interference (MPI) figure of merit, signal-spontaneous noise figure, (equivalent) spontaneous-spontaneous optical bandwidth, forward amplified spontaneous emission (ASE) power level, reverse ASE power level, ASE bandwidth.