This document defines, classifies, and provides a framework of generic tests or measurement methods for characterizing and specifying fibre optic sensors, including their specific components and subassemblies. The requirements of this document apply to all related fibre optic sensor standards that are part of the IEC 61757 series. Other parts of the IEC 61757 series contain requirements that are specific to sensors that measure particular quantities, and to a particular style or variant of such a fibre optic sensor.