A person-support apparatus 10 comprises a lower frame, a support, an upper frame, and 11 right source. Ths support is coupled to the lower frame. The upper is movably supported above the lower frame by the support. The light source is configured to selectively emit light at one of a first wavelength and a second wavelength as a funtion of the height of the upper frame with respect to a reference point in order to indicate the height of the upper frame.
