In long pipes, the aerodynamic conditions are very favourable to (dust) flame acceleration and very severe explosions may result (as for instance in galleries of grain storage and handling facilities). The consequences of such explosions are likely to be disastrous if, at the end of the acceleration process, the flame reaches the ＇detonation＇ regime for which overpressures of several tens of bars are possible. In this paper, it is primarily intended to present the actual state of knowledge concerning dust flame acceleration in pipes and detonations. In addition to this qualitative information, a (critical) review of some correlations linking the geometrical configuration and properties of the mixture to the ＇violence＇ of dust explosions in pipes (maximum flame speed, maximum overpressure) is proposed. In conclusion an account of the means to prevent flame acceleration in pipes is given.