The safety lock system makes this the ideal solution for creating internal platforms for elevator housings at elevated heights. The platforms make it possible to create a stable surface for job site workers and for erecting formwork. These new work platforms make it possible to execute structures inside elevator housings or similar, with minimum measurements of 1.5×1.5 m and up to a maximum of 3.5×3.5 m. With just a few simple crane manoeuvres the platforms can be released and repositioned ready for the next concrete pour.