This part of IEC 60869 applies to fibre optic attenuators. These have all of the following general features: - they are passive in that they contain no opto-electronic or other transducing elements; - they have two ports for the transmission of optical power and attenuate the transmitted power in a fixed or variable fashion; - the ports are optical fibres or optical fibre connectors. This standard establishes uniform requirements for the following: - attenuator requirements; - quality assessment procedures.