It's going to be warm today, so I thought I might head outside with the pressure washer to clean up our brick walkway. Would this also be safe to use on the old (100 years), sound terrazzo floor to our front portico? Following a previous post, I went to the NTMA website, where they recommended a "neutral" cleaner, so I guess I need to steer away from TSP or muriatic acid or anything strong like that - but would appreciate suggestions as to what to use, especially on stained areas.