Rule XX of the Standing Rules of the United States Senate, established by the Senate Committee on Rules and Administration, governs questions of order the within the United States Senate.
Paragraph 1 states a question of order may be raised at any stage of the proceedings. The exception being when the Senate is voting or ascertaining the presence of a quorum. The question unless submitted to the Senate, shall be decided by the Presiding Officer without debate, subject to an appeal to the Senate.
When an appeal is taken, any subsequent question of order which may arise before the decision of such appeal shall be decided by the Presiding Officer without debate. Every appeal from then on shall be decided at once, and without debate. Any appeal may be laid on the table without prejudice to the pending proposition, and shall be held as affirming the decision of the Presiding Officer.
Paragraph 2 states that the Presiding Officer may submit any question of order for the decision of the Senate.