US Patent 10106990 Hazard warning system

A flooring element is provided for a raised floor including removable flooring panels and a supporting structure with a load bearing surface. The flooring element includes a warning element operable for moving between an inactive position in which the warning element is substantially concealed by the surface and an active position in which the warning element projects beyond the surface to form a visual hazard warning indicator. The flooring element may be for example a flooring panel, a stringer, a pedestal, an insert for a pedestal or an insert for inserting between a sub-floor void and a flooring panel.