A Public Safety Network (PSN) is a particular kind of wireless ad hoc network which provides a communication support for Public Safety Users. Use-cases are numerous in terms of both deployment scenarios (e.g. mobile or fixed, small or large scale) and services (Push To Talk, Mail reporting, video streaming). Extreme conditions encountered after an earth quake or floodings may impede the use of any communication infrastructure. Maintaining robust and efficient communications is such harsh conditions is a major challenge. QoS requirements lead previous studies towards TDMA based radio resource management combined with clustering techniques for scalability purposes. In this paper we investigate how both Push To-Talk and Mail Reporting services can be supported in such networks. The key contributions are threefold: i) identification of remaining issues within TDMA/Clustered networks ; ii) proposition of a novel radio resource management protocol ; iii) evaluation of performance gains of the novel solution. We show that both services (Push-To-Talk and Mail reporting) can be supported in a Public Safety Network and that our solution outperforms the previous ones. Finally, we present further identified targeted works to improve our solutions.