scope:

The present document provides the specification of the ITS application Road Hazard Signalling (RHS) based on the cooperative awareness (CA) basic service [1] and the decentralized environmental notification (DEN) basic service [2]. This includes functional and operational requirements of the RHS application for other layers and entities of an ITS-Station on both the originating and the receiving sides.

For the originating side of the RHS application the operational conditions related to the hazard detection and the triggering of the DENM are specified. Furthermore values are defined for use case specific data elements of the DENM and for indication of a message priority to achieve the required timely transmission.

In addition the present document considers performance requirements for the generation and transmission of the CAM and DENM, which enable different levels of RHS, and also collision avoidance and collision mitigation applications.