Expectations at day-1 at the LHC

One of the first measurements that will be made at the LHC by ATLAS will be the properties of inelastic collisions: the central charged particle density and transverse momentum distributions. Current predictions of these distributions by models have large uncertainties in the LHC energy range. We describe the ATLAS minimum bias triggers and the performance of the low transverse momentum track reconstruction. The precision with which the minimum bias distributions can be measured with early data is presented and the uncertainties on the inelastic distributions due to trigger bias discussed. Even with early data, the measurements will be able to distinguish between different models.