Patent ID: 8113314

Claim:
A stair system for a mobile oilfield storage tank, the stair system comprising: a platform subsystem attached to a front wall of the mobile oilfield storage tank, the platform subsystem comprising: a continuous platform suitable for use as a walkway; a support extending from and rigidly attached to the front wall, the support being configure to support the continuous platform, the support forming a gap under the continuous platform; and a retractable platform extension slidingly engaged to the platform subsystem, the platform extension being positioned below the continuous platform while in a retracted position, the retractable platform being configured to slide within the gap formed by the support, the retractable platform being configured for selectively extending the walkway in a direction transverse to the front wall such that the retractable platform provides walking access to a platform subsystem of an adjacent second mobile storage tank; a staircase subsystem comprising: a first staircase member having a first end and a second end, the first end being attached to the platform subsystem, the first staircase member extending in a direction from the front wall of the oilfield mobile storage tank such that the second end of the first staircase member is further from the front wall of the oilfield mobile storage tank than the first end of the first staircase member; and a second staircase member pivotally connected to the second end of the first staircase member; wherein the second staircase member is pivotally rotatable between a retracted mode and an extended mode, wherein, when the second staircase member is in the retracted mode, at least a portion of the second staircase member is positioned above at least a portion of the first staircase member, and wherein, when the second staircase member is in the extended mode, the staircase subsystem is suitable for use as a stairway to the platform; and a hand rail subsystem comprising: a vertical support attached to the first staircase member; and a hand rail comprising: a first hand rail member attached to the vertical support; a second hand rail member pivotally attached to the first hand rail member; and a moveable support pivotally attached to the vertical support; wherein the second hand rail member is pivotally rotatable relative to the first hand rail member, and wherein the moveable support is pivotally rotatable relative to the vertical support.