Abstract: A device particularly suited for blocking access and locking out a circuit breaker or other switch of the type having a solid stem without holes, which includes a base having an opening for positioning on the switch base and receiving the switch stem, a clamping member, and a thumb screw for operation with the clamping member to clamp the device onto the switch stem to immobilize it. The device further includes a cover which is pivoted over a structure forming an aperture for receiving a lock shackle, the cover blocking operation of the thumb screw when the lock shackle is positioned and secured in said aperture.

Abstract: A valve lock has a body and a moveable jaw for releasably gripping a lever handle of the valve against the body. The jaw has a threaded shaft that extends through a hole in the body, and a locking cleat is slidable on the threaded shaft. An arm is attached to the shaft between the body and the locking cleat, and is rotatable about the shaft to abut either the valve or a pipe connected to the valve. A hand wheel is threaded onto the shaft and can be tightened against the locking cleat which then forces the arm against the body to inhibit rotation of the arm about the shaft. The locking cleat has an aperture for receiving the shackle of a padlock, and the hand wheel has a plurality of notches in an exterior surface with one of the notches receiving the shackle to restrict movement of the wheel along the shaft.