This Recommendation uses the framework defined in ITU-T Recommendation X.1081, The telebiometric multimodal model - A framework for the specification of security and safety aspects of telebiometrics, for optimal safety and security in telebiometrics. It gives names and symbols for quantities and units concerned with emissions from the human body that can be detected by a sensor, and with effects on the human body produced by the telebiometric devices in his environments. It is applicable to both physiology and biometrics (the measurement of physiological, biological and behavioral characteristics). A taxonomy of wetware and hardware/software interactions is defined. Thresholds are specified using the set of international system of quantities (ISQ) and the related set of international system of units (SI).