Stop bar for creating a temporary safety space within an elevator hoistway

The present invention relates to a device and procedure for creating and securing a temporary safety space within an elevator hoistway (12) such that a service or maintenance technician can work with impunity from a car (2) entering the safety space. In particular, the invention provides a stop bar (20) for installation between and in engagement with opposing guide rails (12) of the hoistway (12) to prevent upward or downward movement of the car (2) or a counterweight.