Unprotected stair to open mezzanine

Hi everyone,

In reviewing Chapter 10 egress from mezzanines would the following comply with IBC 2018? Mercantile space, unsprinklered, Type IIIB. 60 inch clear wide staircase, open on all sides, from grade level floor to mezzanine. the stair is not a fire rated or smoke protected staircase. would a second staircase be required that is in fact enclosed and protected?