Abstract: A safety support structure is provided which comprises a post with upper and lower ends adapted to abut firmly against a ceiling surface and a floor surface, and an accessory mounting region disposed between the upper end and the lower end. The post has a length adjustment means and a pressure indicating means to indicate whether the pressure on the structure, when positioned between a floor surface and ceiling surface, lies inside or outside a predetermined range so as to avoid inflicting damage on the floor or ceiling and to inhibit slippage of the post. The accessory mounting region carries mounting formations, to cooperate with laterally extending support accessories clamped to it and positively to resist axial and/or rotational displacement of the support accessories relative to the post.