Abstract: A level holder (10, 10') with a level holding assembly (14, 14') has slots (22, 26, 28, 30) or pegs (58, 60) capable of supporting a level in two different orientations relative to the level holding assembly (14, 14') and a mounting assembly (38, 38') for attaching the level holding assembly to either vertical or horizontal scaffolding members (34, 32) associated with the two different orientations enabling the level holding assembly (14, 14') to support one or more levels (16) in a substantially vertical position regardless of whether attached to a vertical or horizontal member. In one form of the mounting assembly (38) a lateral member (28) used to provide underlying support for a level (16) also functions as one side of a C-clamp assembly (40, 42, 44, 46, 48, 50, 52). In another form of the mounting assembly (38'), another C-clamp having a pair of nonpivotal, resilient arms (64, 66) adapted for attachment to either cylindrical vertical members (34) or planar members (32) is used for attachment.

Abstract: Guard rail actuated safety apparatus (42, FIG. 1; 89, FIGS. 5A and 5B) is operative to prevent simultaneous lowering of both of a pair of guard rails (26, 28) to inoperative positions in which they are ineffective to prevent a patient from falling off the edge of a patient support assembly 12. In one embodiment, the guard rails are secured together by a cable (44) which holds the guard rails against concurrent lowering. In an electromechanical embodiment, a controller (89, FIG. 5) senses the guard rail (26, 28) position, and blocks the lowering of either guard rail (26, 28) whenever the other is lowered. In addition, or alternatively, the controller (89) actuates a brake 146, sounds an alarm (136), raises the guard rails (26, 28) after a time delay (158), deactuates a drive motor (118) for a movable or adjustable patient support assembly (12) or releases air from a pneumatic mattress (12A').