A ceiling ladder having a plurality of sections that can be climbed by a user when in an unfolded position into an attic and that can be folded together into a retracted position to be stored above the ceiling. The ladder has a deep step, which has a width greater than the width of other steps of the ladder, in which is located between about 2-5 feet from the floor when the ladder is in the unfolded position so that a user can stand on the deep step and place objects into the attic without having to climb into the attic.

A cluster tool system, including: a load lock; a first wafer transfer module; a buffer module; a second wafer transfer module; wherein the load lock, the first wafer transfer module, the buffer module, and the second wafer transfer module are positioned in a linear arrangement; a first process module connected to the first wafer transfer module on a first side of the linear arrangement; a second process module connected to the second wafer transfer module on the first side; a third process module connected to the first wafer transfer module on a second side of the linear arrangement that is opposite the first side; a fourth process module connected to the second wafer transfer module on the second side; a first ladder assembly connected to the buffer module on the first side; a second ladder assembly connected to the buffer module on the second side.

A retro-fit installation modifies the existing pool ladder structure of an existing in-ground or above-ground swimming pool to support an underwater swim out platform structure. In some versions, the ladder rails of the existing pool ladder are used to support the underwater platform, while in others the existing pool ladder rails are replaced with new tubular platform rails specifically designed to support the underwater platform structure. Other versions are adapted for installations in a round pool or at a corner of a rectangular pool.

An attachable platform providing a work surface affixed to the top cap of the ladder. The device includes a work surface and rails along the exterior edges of the work surface and slots therein. The slots receive an attachment device such as a hook and loop strap to attach the platform to the ladder. Protrusions are found on the back surface of the platform and are designed to accommodate the top cap of a ladder.

A ladder assembly is provided, including the following: a mounting plate that connects to a side surface of a module in a fabrication facility; a step ladder, including, a ladder frame having an arm that connects to the mounting plate at a first joint, wherein the step ladder rotates about the first joint between a lowered position and a raised position, the lowered positioned defined by resting of the step ladder on a floor of the fabrication facility, and the raised position defined by suspension of the step ladder off of the floor and substantially over the module; a plurality of step plates connected to the ladder frame, the step plates defining step surfaces for a user when the step ladder is in the lowered position. A sleeve extends below one of the step plates of the step ladder, to house electronic equipment used in the fabrication facility.

A shelf apparatus configured for temporary attachment to a ladder deployed in a working position includes a planar tray supported at its inboard end by a rung or top plate of the ladder, left and right support arms pivotably attached to opposite sides of the tray near its inboard end, a rigid linkage coupling the tray to the left and right support arms, and an adjustable clamping mechanism for clamping the tray to the rung or top plate. In use with a straight ladder, the tray is horizontally suspended under the inclined frame of the deployed ladder, the support arms are raised to rest against the inclined rails of the ladder above the tray, the rigid linkage vertically supports the tray from the support arms, and the clamping mechanism secures the tray to the rung.

A step platform for use with a stepladder having front and back legs. The front leg has a plurality of steps. The step platform includes a tread portion connected to a locking portion. The tread portion has a front portion configured to rest upon a selected one of the steps and a back portion configured to extend from the front portion toward the back leg beyond the selected step. The locking portion extends alongside a front portion of the selected step and at least partially wraps around a lower edge of the front portion.

An intermediate rung apparatus for use with a ladder includes a first hook, legs, and an intermediate rung. The first hook is configured to extend over a rung of the ladder and couple the intermediate rung apparatus to the ladder. The intermediate rung apparatus also includes legs extending from the first hook. The legs are configured to extend in a downward direction substantially parallel to vertical supports of the ladder when the intermediate rung apparatus is coupled to the ladder. The intermediate rung apparatus further includes an intermediate rung connected to the legs and configured to extend in a direction substantially parallel to the rung of the ladder when the intermediate rung apparatus is coupled to the ladder. In some embodiments, a mount may be used to support the intermediate rung apparatus and/or the ladder.

Embodiments of tree climbing sticks adapted to be secured to a tree and provide a tree climbing assist are provided. In one embodiment, for example, a tree climbing stick is provided including a retractable aider step. The retractable aider step is adapted to be extended from the tree climbing stick during use and at least partially retracted within the tree climbing stick for transport and storage. In another embodiment, a tree climbing stick is adapted to be stacked and nested with another tree climbing stick. In this embodiment, a clip of the tree climbing stick is adapted to engage a button of an adjacent tree climbing stick and standoffs of the tree climbing sticks are adapted to nest so that the tree climbing sticks can be stacked vertically without axially extending from each other.

A step platform for use with a stepladder having front and back legs. The front leg has a plurality of steps. The step platform includes a tread portion connected to a locking portion. The tread portion has a front portion configured to rest upon a selected one of the steps and a back portion configured to extend from the front portion toward the back leg beyond the selected step. The locking portion extends alongside a front portion of the selected step and at least partially wraps around a lower edge of the front portion.