Stairways

Claim 1

A PREFABRICATED METAL STAIRWAY COMPRISING A PERMANENETLY SELF-SUPPORTING STAIRWAY UNIT HAVING A RECTANGLE FORMED BY HORIZONTAL BASE MEMBERS, FIRST, SECOND, THIRD, FOURTH VERTICAL MEMBERS ATTACHED AT CORNERS OF SAID RACTANGLE IN SUCCESSIVE ROTATIONAL POSITIONS, A FIRST HORIZONTAL BAR EXTENDING BETWEEN SAID SECOND AND THIRD VERTICAL MEMBERS AT AN INTERMEDIATE POSITION ALONG SAID VERTICAL MEMBERS, A SECOND HORIZONTAL BAR EXTENDING BETWEEN SAID SECOND AND THIRD VERTICAL MEMBERS AT HIGHER POSITION THAN SAID FIRST HORIZONTAL BAR, A THRID HORIZONTAL BAR EXTENDING BETWEEN SAID FIRST AND FOURTH VERTICAL MEMBERS AT AN INTERMEDIATE POSITION ALONG SAID VERTICAL MEMBERS, A FOURTH HORIZONTAL BAR EXTENDING BETWEEN SAID FIRST AND FOURTH VERTICAL MEMBERS AT A HIGHER POSITION THAN SAID THIRD HORIZONTAL MEMBER, SAID HORIZONTAL BARS EACH POSITIONED AT A DIFFERENTIAL HEIGHT ABOVE SAID RECTANGLE FORMED BY SAID HORIZONTAL BASE MEMBERS, AT LEAST THREE RUNS OF STAIRS HAVING DIAGONAL MEMBERS FORMING THE SIDES THEREOF WITH SAID DIAGONALS CONNECTED TO AND BETWEEN SAID HORIZONTAL BARS, AN ADDITIONAL RUN OF STAIRS HAVING DIAGONAL MEMBERS FORMING THE SIDES THEREOF WITH AT LEAST ONE OF SAID DIAGONALS CONNECTED BETWEEN THE LOWERMOST OF SAID HORIZONTAL BARS AND AT LEAST ONE OF SAID HORIZONTAL BASE MEMBERS, SAID DIAGONAL MEMBERS OF THE UPPERMOST RUN OF SAID AT LEAST THREE RUNS OF STAIRS CONNECTED BETWEEN SAID SECOND AND FOURTH HORIZONTAL BARS, SAID SECOND HORIZONTAL BAR LOCATED AT A LOWER HEIGHT THAN SAID FOURTH HORIZONTAL BAR WITH SAID FIRST AND FOURTH VERTICAL MEMBERS CONNECTED TO SAID FOURTH HORIZONTAL BAR AND EXTENDING TO A HEIGHT ABOVE THE HEIGHT OF SAID SECOND AND THIRD VERTICAL MEMBERS, CONNECTED TO SAID SECOND HORIZONTAL BAR.