Simulation modelling of the observability of low Earth orbit (LEO) objects was performed using optical surveillance facilities depending on their geographic location and time of year. Orbital data for LEO objects from the open-access catalogue of the near-Earth space objects of the US Combined Space Operations Center (CSpOC) were taken as the initial data for the simulation. The simulation results revealed a complex relationship between the pattern of observability of a LEO object, its orbital parameters and location of the optical surveillance facility, in particular, for Sun-synchronous orbits (SSO) and observing facilities located near the equator. We also discuss variations in the frequency of passes of LEO objects into the field of view (FOV) and in the duration of their observation while passing through the FOV for optical surveillance facilities at three alternative locations. The obtained results and modelling techniques can be further used in the location planning of new optical observing facilities.