Applies to optical fibre amplifiers using active fibres, containing rare-earth dopants, presently commercially available. Establishes uniform requirements for accurate and reliable measurements, by means of the filtered optical power meter test method, of the following OFA parameters:- out-of-band insertion loss; - out-of-band reverse insertion loss. The main significant changes are the following: a) the applicability has been extended to all commercially available optical amplifiers, b) Clause 9, EMC, has been added.