In one embodiment a power-tool operating device includes an operating unit that can be actuated by an operator. The power-tool operating device further includes an electronic unit to switch at least one energy supply of a drive unit based on the actuation of the operating element. The electronic unit has a locking switching function and a dead-man's switching function that can be selected at least partly automatically based on at least one of an actuation characteristic quantity of the operating element and sensed sensor characteristic quantity.

A deadman switch system includes a primary deadman switch actuator and a secondary deadman switch actuator for controlling the flow of an air/abrasive mix through a flow line of a delivery system. The secondary deadman switch is positioned in series with a primary deadman switch actuator such that the controlled flow will not function unless first the primary deadman switch and then the secondary switch are closed. The preferred embodiment of the switch is a low-profile configuration adapted to be mounted in axial alignment with the flow line in a manner to minimize interference with normal operation of the system. The switch can include multiple open/close elements, for selectively controlling different flow functions.

A nozzle arrangement for use in expelling pressurized fluid includes a dead man control. The dead man control has a manually operable control part movable between a non-operating position, which prevents operation of the nozzle arrangement, and an operating position, and biased towards the non-operating position. The manually operable control part is pivotably coupled relative to a nozzle holder of the nozzle arrangement, which extends away from the pivotal coupling substantially towards a distal end of a nozzle part of the nozzle arrangement. The manually operable control part includes a handle part which in the operating position is substantially against and aligned with the nozzle part.

A safety apparatus to facilitate safe operation of an industrial machine. The safety apparatus includes a glove body, a coupling element, and a latch assembly. The glove body includes a hand portion and a contiguous wrist portion configured to entirely cover a hand, thumb, fingers, and wrist of a user. The coupling element is mechanically fixed to a dorsal side of the wrist portion near the bottom edge and includes a loop member engaged with an attachment ring. The latch assembly is releasably coupled to the attachment ring and securely attached to a kill cord configured to releasably engage a control switch of an industrial machine.