This European Standard defines the mandatory and optional requirements for the medium specific Physical and Data Link Layer of HBES Radio Frequency.Data Link Layer interfaces and general definitions that are medium independent are given in EN 50090 4 1.This European standard defines the requirements for HBES RF Ready and HBES RF Multi devices. HBES RF Ready is a single RF channel system. HBES RF Multi is an RF multichannel evolution of HBES RF Ready system with 2 additional RF channels for fast reaction time products and 2 RF channels for slow reaction time products.HBES RF Multi, specified below provides the following features:-more reliability in Frame transmissions in presence of interferers.-more efficiency when more HBES RF products are installed at the same location.-mixing of permanent and non-permanent receiving products.-mixing of fast and slow reaction time devices.-Listen Before Talk.Fast RF channels are mainly intended to be used with human controlled applications like for example lights, shutters… Slow RF channels are mainly intended to be used with non-permanent receivers for automatic applications like sensors (smoke, temperature, wind, etc.), heating control, etc.Compatibility issues with products in compliance with the former HBES RF specification (HBES RF 1.1) and the new versions are considered in Clause 7 at the end of this document.