Safety is a great part of the Buran development. The safety or the probability of success of the flight, i.e. the fact that the crew stay in life and the equipment is not damaged was given at the beginning of the project as a requirement. This probability was fixed at 0.99-0.995.
The studies made showed that the installation of a rescue system of the crew is not always easy to make, because of the complexity of the systems and the characteristics of the Buran-Energia structure. The detailed diagnoses of the equipment in real time, the various trajectories are as many problems as it is necessary to get rid of to ensure the survival of the crew. The most complex scenarios are taking place at the beginning of the launcher between 90 and 135 s, because the choice must be made between ejecting the crew (thanks to the ejector seats) or immediately separating the shuttle from Energia for an emergency landing.
By taking into account all the systems and safety measures that it is on the blocks of the first stage, the second stage or the Buran shuttle, one can advance in an unquestionable way that an exploitation accident like the one wich struck the Challenger shuttle (loss of the totality of the crew) is impossible for Buran-Energia.