I believe the key point here is 'POSITIVELY OPENED MECHANICALLY.' Positively opened switches ensure that the switch opens completely whenever the user toggles it. They don't rely on springs and are both simple and safe. Typically, a piece of metal is mechanically linked to the lever, and when the lever is moved, it compels the contact to open. They are usually slide type switches. In contrast, non-safety switches depend on springs. There's a possibility that the spring might malfunction, causing the contact to remain closed even after the user moves the lever. Therefore, it's of crucial importance that the type of switch used for 'INSPECTION/NORMAL' or 'HALL/CALL BYPASS' functions is of the positively opened kind.