Railway transport is a complex technical system with telecommunication being one of its constituent parts. Technical condition of the objects of the telecommunication division impacts directly on the traffic process. Therefore, to ensure the required indices of the traffic process reliability it is necessary to provide for a pre-set factor for availability of services that are needed for safe control of train traffic. According to the methodology of management of resources, risks and dependability at life cycle stages (URRAN) (Gapanovich et al. in Dependability 2:4–22, 2015. https://doi.org/10.21683/1729-2646-2015-0-2-4-22 ) implemented on Russian railways, resources are managed in the telecommunication division based on the risk level criterion: if a risk is tolerable then the objects of the telecommunication division ensure the compliance with the traffic process requirements. If risks exceed the tolerable values it is necessary to take measures aimed at the modernization of the objects, or at the improvement of their technical maintenance. This approach is aimed at the optimization of cost of the life cycle of the objects of the telecommunication division. Order of estimation of risks related to the functional faults of telecommunication objects includes the identification of undesirable events that lead to the violations of availability of services of railway telecommunication, and consequently to train delays. Then the frequencies of these undesirable events are estimated, the amount of damage is defined. This data is initial data used to construct matrices of risks of the functional faults of telecommunication objects. The article contains calculation expressions for the construction of risk matrices and the rules of decision making in relation to tolerability (or intolerability) of the assigned risk level. The article also describes the example of estimation of risk related to the functional faults of telecommunication objects based on the statistics of undesirable events held on the Russian railways during several years of observation, with the description of possible measures that can be taken to control each category of the risk.